http: improve performance for end() with known-length string - #65466

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pimterry:h1-clean-end-perf
Aug 24, 2026
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http: improve performance for end() with known-length string#65466
nodejs-github-bot merged 1 commit into
nodejs:mainfrom
pimterry:h1-clean-end-perf

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@pimterry

@pimterrypimterry commented Aug 21, 2026

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When you call end(data) on an outgoing HTTP request, we previously wrote the data, and then ran _send('', ...) just to trigger flushing the headers, which resulted in an extra zero-byte write call and bonus nextTick before 'finish'.

When the length is known and content-length is used (not chunking, so we don't need a terminator) we can skip this completely: prep the content-length header explicitly, and combine the finish into the existing write step.

This drops a nextTick, and goes from 2 write calls to 1 for the very common case of response.end(data) with a string, and for buffer data goes from 3 writes to 2.

In practice, in the tiny benchmark here which I think represents a very common use case (small API responses) I see this boosting HTTP RPS by up to 9% for writes up to 1KB or so. For larger responses the response write time starts to outweigh this, but I still see 3% RPS boost at 16KB. Needs autocannon to hit the rates required, you can test yourself with:

node benchmark/compare.js --old ./node-main --new ./node-pr --runs 20 --set benchmarker=autocannon --filter end-string http

Added a new test confirming the specific details and edge cases this touches, and updated one existing test which specifically asserted that end(data) triggered two writes, including the empty one.

@pimterry
http: improve performance with known-length calls to end()
659d6b9
This boosts RPS performance for the common API case where you call
`res.end(data)` with the entire response by up to 9%.
Signed-off-by: Tim Perry <pimterry@gmail.com>
@nodejs-github-bot

nodejs-github-bot commented Aug 21, 2026

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Review requested:

  • @nodejs/http
  • @nodejs/net
  • @nodejs/performance

@nodejs-github-botnodejs-github-bot added http Issues and PRs related to the http subsystem. needs-ci PRs that need a full CI run. labels Aug 21, 2026
mcollina
mcollina approved these changes Aug 21, 2026
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lgtm

@mcollina
mcollina requested a review from anonrigAugust 21, 2026 19:24
@codecov

codecovBot commented Aug 21, 2026•
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Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 90.13%. Comparing base (15940ef) to head (659d6b9).
⚠️ Report is 61 commits behind head on main.

Additional details and impacted files
@@ Coverage Diff @@## main #65466 +/- ##
==========================================
- Coverage 90.14% 90.13% -0.01% 
==========================================
Files 751 751 Lines 252298 252333 +35 Branches 47446 47449 +3 ==========================================
+ Hits 227436 227451 +15 - Misses 16175 16186 +11 - Partials 8687 8696 +9
Files with missing linesCoverage Δ
lib/_http_outgoing.js97.76% <100.00%> (-0.02%)⬇️

... and 34 files with indirect coverage changes

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@pimterrypimterry added the request-ci Add this label to start a Jenkins CI on a PR. label Aug 21, 2026
@github-actionsgithub-actionsBot removed the request-ci Add this label to start a Jenkins CI on a PR. label Aug 22, 2026
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nodejs-github-bot commented Aug 22, 2026

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CI: https://ci.nodejs.org/job/node-test-pull-request/76211/

@bjohansebasbjohansebas added the needs-benchmark-ci PRs that need a benchmark CI run. label Aug 22, 2026
@pimterry

pimterry commented Aug 24, 2026

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@bjohansebas benchmark label was a good suggestion. I've done a run here.

Unfortunately it seems like the microbenchmark job is broken generally (cc @nodejs/build) and all recent jobs have failed with:

++ Rscript benchmark/compare.R
Error: package or namespace load failed for ‘ggplot2’ in dyn.load(file, DLLpath = DLLpath, ...):
unable to load shared object '/usr/local/lib/R/site-library/rlang/libs/rlang.so':
/usr/local/lib/R/site-library/rlang/libs/rlang.so: undefined symbol: SETLENGTH
Execution halted

I've manually extracted the CSV from the console output to get some numbers though, and run node-benchmark-compare on the result, which gives:

Details
 confidence improvement accuracy (*) (**) (***)
http/bench-parser-fragmented.js n=100000 frags=2 len=16 -0.20 % ±1.06% ±1.42% ±1.85%
http/bench-parser-fragmented.js n=100000 frags=2 len=8 -0.01 % ±0.94% ±1.25% ±1.63%
http/bench-parser-fragmented.js n=100000 frags=4 len=16 -0.17 % ±0.77% ±1.02% ±1.33%
http/bench-parser-fragmented.js n=100000 frags=4 len=8 -0.57 % ±0.64% ±0.85% ±1.11%
http/bench-parser-fragmented.js n=100000 frags=8 len=16 -0.07 % ±0.84% ±1.12% ±1.45%
http/bench-parser-fragmented.js n=100000 frags=8 len=8 0.43 % ±0.78% ±1.04% ±1.35%
http/bench-parser.js n=100000 len=16 0.20 % ±0.93% ±1.24% ±1.61%
http/bench-parser.js n=100000 len=32 0.03 % ±0.68% ±0.90% ±1.17%
http/bench-parser.js n=100000 len=4 0.60 % ±1.08% ±1.43% ±1.86%
http/bench-parser.js n=100000 len=8 0.32 % ±1.11% ±1.47% ±1.92%
http/check_invalid_header_char.js n=1000000 input='' 1.25 % ±2.48% ±3.30% ±4.30%
http/check_invalid_header_char.js n=1000000 input='\t\t\t\t\t\t\t\t\t\tFoo bar baz' 0.39 % ±1.66% ±2.21% ±2.88%
http/check_invalid_header_char.js n=1000000 input='\x7F' * 4.92 % ±3.90% ±5.19% ±6.75%
http/check_invalid_header_char.js n=1000000 input='1' -0.41 % ±3.47% ±4.62% ±6.02%
http/check_invalid_header_char.js n=1000000 input='20091' -0.50 % ±3.85% ±5.12% ±6.66%
http/check_invalid_header_char.js n=1000000 input='close' 0.49 % ±3.34% ±4.44% ±5.78%
http/check_invalid_header_char.js n=1000000 input='en-US' -0.66 % ±3.59% ±4.77% ±6.21%
http/check_invalid_header_char.js n=1000000 input='foo\nbar' -1.88 % ±2.70% ±3.60% ±4.70%
http/check_invalid_header_char.js n=1000000 input='group_acmeair' 0.85 % ±1.82% ±2.42% ±3.16%
http/check_invalid_header_char.js n=1000000 input='gzip' -0.60 % ±3.29% ±4.37% ±5.70%
http/check_invalid_header_char.js n=1000000 input='keep-alive' -1.28 % ±2.16% ±2.88% ±3.75%
http/check_invalid_header_char.js n=1000000 input='LONG_AND_INVALID' 0.08 % ±1.13% ±1.51% ±1.97%
http/check_invalid_header_char.js n=1000000 input='private' 1.00 % ±2.68% ±3.57% ±4.65%
http/check_invalid_header_char.js n=1000000 input='SAMEORIGIN' 1.36 % ±2.81% ±3.74% ±4.88%
http/check_invalid_header_char.js n=1000000 input='Sat, 07 May 2016 16:54:48 GMT' 0.79 % ±1.41% ±1.87% ±2.44%
http/check_invalid_header_char.js n=1000000 input='text/html; charset=utf-8' -0.12 % ±1.41% ±1.88% ±2.45%
http/check_invalid_header_char.js n=1000000 input='text/plain' -1.49 % ±2.96% ±3.95% ±5.14%
http/check_invalid_header_char.js n=1000000 input='中文呢' 1.95 % ±2.71% ±3.61% ±4.69%
http/check_is_http_token.js n=1000000 key=':' -0.22 % ±2.22% ±2.96% ±3.85%
http/check_is_http_token.js n=1000000 key=':alternate-protocol' 2.82 % ±4.07% ±5.42% ±7.06%
http/check_is_http_token.js n=1000000 key='((((())))' -1.22 % ±2.75% ±3.71% ±4.91%
http/check_is_http_token.js n=1000000 key='@@' 0.52 % ±2.14% ±2.85% ±3.71%
http/check_is_http_token.js n=1000000 key='Accept-Ranges' 0.51 % ±2.25% ±2.99% ±3.90%
http/check_is_http_token.js n=1000000 key='alt-svc' -0.09 % ±2.23% ±2.97% ±3.87%
http/check_is_http_token.js n=1000000 key='alternate-protocol:' -0.94 % ±2.08% ±2.77% ±3.61%
http/check_is_http_token.js n=1000000 key='alternate-protocol' -1.19 % ±2.32% ±3.09% ±4.03%
http/check_is_http_token.js n=1000000 key='Cache-Control' -0.96 % ±2.14% ±2.85% ±3.71%
http/check_is_http_token.js n=1000000 key='Connection' 0.78 % ±2.39% ±3.19% ±4.15%
http/check_is_http_token.js n=1000000 key='Content-Encoding' * -2.76 % ±2.26% ±3.01% ±3.92%
http/check_is_http_token.js n=1000000 key='content-length' 0.93 % ±2.27% ±3.02% ±3.92%
http/check_is_http_token.js n=1000000 key='Content-Location' -0.15 % ±2.52% ±3.35% ±4.36%
http/check_is_http_token.js n=1000000 key='content-type' -0.49 % ±2.55% ±3.39% ±4.41%
http/check_is_http_token.js n=1000000 key='Content-Type' 0.46 % ±2.58% ±3.43% ±4.47%
http/check_is_http_token.js n=1000000 key='date' 0.62 % ±2.42% ±3.22% ±4.19%
http/check_is_http_token.js n=1000000 key='ETag' -2.60 % ±3.97% ±5.32% ±7.01%
http/check_is_http_token.js n=1000000 key='Expires' ** 3.69 % ±2.64% ±3.52% ±4.59%
http/check_is_http_token.js n=1000000 key='Keep-Alive' -0.03 % ±2.59% ±3.45% ±4.48%
http/check_is_http_token.js n=1000000 key='Last-Modified' -0.99 % ±2.34% ±3.12% ±4.07%
http/check_is_http_token.js n=1000000 key='location' 0.79 % ±2.44% ±3.25% ±4.23%
http/check_is_http_token.js n=1000000 key='server' 0.37 % ±2.46% ±3.27% ±4.25%
http/check_is_http_token.js n=1000000 key='Server' * 3.70 % ±3.00% ±4.00% ±5.23%
http/check_is_http_token.js n=1000000 key='status' ** -4.32 % ±3.09% ±4.13% ±5.40%
http/check_is_http_token.js n=1000000 key='TCN' -0.86 % ±1.00% ±1.33% ±1.73%
http/check_is_http_token.js n=1000000 key='Transfer-Encoding' -1.00 % ±2.32% ±3.09% ±4.02%
http/check_is_http_token.js n=1000000 key='Vary' -0.56 % ±1.47% ±1.95% ±2.54%
http/check_is_http_token.js n=1000000 key='version' 1.90 % ±2.74% ±3.65% ±4.75%
http/check_is_http_token.js n=1000000 key='x-frame-options' 0.57 % ±2.05% ±2.73% ±3.55%
http/check_is_http_token.js n=1000000 key='x-xss-protection' -1.39 % ±2.29% ±3.06% ±3.99%
http/check_is_http_token.js n=1000000 key='中文呢' -1.00 % ±4.47% ±6.01% ±7.92%
http/chunked.js duration=5 c=100 len=1 n=1 benchmarker='wrk' -0.19 % ±0.68% ±0.91% ±1.18%
http/chunked.js duration=5 c=100 len=1 n=16 benchmarker='wrk' 0.41 % ±0.78% ±1.03% ±1.35%
http/chunked.js duration=5 c=100 len=1 n=4 benchmarker='wrk' 0.61 % ±2.08% ±2.76% ±3.60%
http/chunked.js duration=5 c=100 len=1 n=8 benchmarker='wrk' 0.13 % ±0.81% ±1.07% ±1.40%
http/chunked.js duration=5 c=100 len=256 n=1 benchmarker='wrk' -0.10 % ±0.70% ±0.93% ±1.21%
http/chunked.js duration=5 c=100 len=256 n=16 benchmarker='wrk' -0.70 % ±0.73% ±0.97% ±1.26%
http/chunked.js duration=5 c=100 len=256 n=4 benchmarker='wrk' -0.58 % ±1.84% ±2.45% ±3.18%
http/chunked.js duration=5 c=100 len=256 n=8 benchmarker='wrk' 0.11 % ±0.87% ±1.16% ±1.51%
http/chunked.js duration=5 c=100 len=64 n=1 benchmarker='wrk' -0.26 % ±0.60% ±0.80% ±1.04%
http/chunked.js duration=5 c=100 len=64 n=16 benchmarker='wrk' 0.56 % ±0.63% ±0.84% ±1.10%
http/chunked.js duration=5 c=100 len=64 n=4 benchmarker='wrk' 0.08 % ±1.81% ±2.41% ±3.15%
http/chunked.js duration=5 c=100 len=64 n=8 benchmarker='wrk' 0.26 % ±0.75% ±1.00% ±1.30%
http/client-request-body.js method='end' len=1024 type='asc' dur=5 -0.06 % ±0.69% ±0.92% ±1.20%
http/client-request-body.js method='end' len=1024 type='buf' dur=5 0.01 % ±0.76% ±1.02% ±1.32%
http/client-request-body.js method='end' len=1024 type='utf' dur=5 -0.28 % ±0.59% ±0.79% ±1.03%
http/client-request-body.js method='end' len=256 type='asc' dur=5 -0.49 % ±0.67% ±0.90% ±1.17%
http/client-request-body.js method='end' len=256 type='buf' dur=5 * -0.75 % ±0.68% ±0.90% ±1.18%
http/client-request-body.js method='end' len=256 type='utf' dur=5 0.03 % ±0.62% ±0.83% ±1.08%
http/client-request-body.js method='end' len=32 type='asc' dur=5 -0.01 % ±0.56% ±0.75% ±0.98%
http/client-request-body.js method='end' len=32 type='buf' dur=5 -0.37 % ±0.60% ±0.79% ±1.03%
http/client-request-body.js method='end' len=32 type='utf' dur=5 -0.16 % ±0.62% ±0.83% ±1.08%
http/client-request-body.js method='write' len=1024 type='asc' dur=5 -0.16 % ±0.78% ±1.03% ±1.34%
http/client-request-body.js method='write' len=1024 type='buf' dur=5 -0.34 % ±0.68% ±0.90% ±1.17%
http/client-request-body.js method='write' len=1024 type='utf' dur=5 0.06 % ±0.78% ±1.04% ±1.35%
http/client-request-body.js method='write' len=256 type='asc' dur=5 0.27 % ±0.70% ±0.93% ±1.21%
http/client-request-body.js method='write' len=256 type='buf' dur=5 0.09 % ±0.76% ±1.02% ±1.32%
http/client-request-body.js method='write' len=256 type='utf' dur=5 0.49 % ±0.59% ±0.79% ±1.03%
http/client-request-body.js method='write' len=32 type='asc' dur=5 -0.40 % ±0.64% ±0.86% ±1.11%
http/client-request-body.js method='write' len=32 type='buf' dur=5 -0.21 % ±0.65% ±0.86% ±1.12%
http/client-request-body.js method='write' len=32 type='utf' dur=5 0.02 % ±0.60% ±0.79% ±1.03%
http/cluster.js duration=5 c=50 len=1024 type='buffer' benchmarker='wrk' 0.13 % ±0.46% ±0.62% ±0.81%
http/cluster.js duration=5 c=50 len=1024 type='bytes' benchmarker='wrk' -0.11 % ±0.38% ±0.50% ±0.66%
http/cluster.js duration=5 c=50 len=102400 type='buffer' benchmarker='wrk' -0.24 % ±0.49% ±0.65% ±0.85%
http/cluster.js duration=5 c=50 len=102400 type='bytes' benchmarker='wrk' 0.14 % ±0.80% ±1.06% ±1.38%
http/cluster.js duration=5 c=50 len=4 type='buffer' benchmarker='wrk' -0.23 % ±0.29% ±0.39% ±0.51%
http/cluster.js duration=5 c=50 len=4 type='bytes' benchmarker='wrk' 0.00 % ±0.51% ±0.67% ±0.88%
http/cluster.js duration=5 c=500 len=1024 type='buffer' benchmarker='wrk' ** -0.77 % ±0.50% ±0.67% ±0.87%
http/cluster.js duration=5 c=500 len=1024 type='bytes' benchmarker='wrk' -0.18 % ±0.65% ±0.86% ±1.12%
http/cluster.js duration=5 c=500 len=102400 type='buffer' benchmarker='wrk' -0.18 % ±0.59% ±0.78% ±1.02%
http/cluster.js duration=5 c=500 len=102400 type='bytes' benchmarker='wrk' 0.28 % ±0.72% ±0.95% ±1.24%
http/cluster.js duration=5 c=500 len=4 type='buffer' benchmarker='wrk' -0.25 % ±0.47% ±0.62% ±0.81%
http/cluster.js duration=5 c=500 len=4 type='bytes' benchmarker='wrk' -0.36 % ±0.52% ±0.70% ±0.91%
http/create-clientrequest.js e=1 arg='options' url='idn' 2.09 % ±7.80% ±10.38% ±13.50%
http/create-clientrequest.js e=1 arg='options' url='long' -9.98 % ±14.10% ±18.77% ±24.46%
http/create-clientrequest.js e=1 arg='options' url='wpt' -4.69 % ±6.75% ±8.98% ±11.70%
http/create-clientrequest.js e=1 arg='string' url='idn' -4.15 % ±10.23% ±13.61% ±17.71%
http/create-clientrequest.js e=1 arg='string' url='long' -0.93 % ±12.77% ±16.99% ±22.12%
http/create-clientrequest.js e=1 arg='string' url='wpt' 0.60 % ±11.36% ±15.12% ±19.68%
http/create-clientrequest.js e=1 arg='URL' url='idn' 0.87 % ±9.17% ±12.20% ±15.88%
http/create-clientrequest.js e=1 arg='URL' url='long' -5.01 % ±10.02% ±13.35% ±17.41%
http/create-clientrequest.js e=1 arg='URL' url='wpt' 1.99 % ±8.00% ±10.64% ±13.85%
http/end-string.js duration=5 c=50 len=1024 benchmarker='wrk' *** 10.48 % ±0.81% ±1.08% ±1.41%
http/end-string.js duration=5 c=50 len=102400 benchmarker='wrk' *** 2.47 % ±0.50% ±0.66% ±0.86%
http/end-string.js duration=5 c=50 len=16384 benchmarker='wrk' *** 5.59 % ±0.89% ±1.19% ±1.55%
http/end-string.js duration=5 c=50 len=4 benchmarker='wrk' *** 9.92 % ±0.82% ±1.10% ±1.43%
http/end-string.js duration=5 c=50 len=64 benchmarker='wrk' *** 8.43 % ±0.71% ±0.94% ±1.23%
http/end-vs-write-end.js duration=5 method='end' c=100 len=1048576 type='asc' benchmarker='wrk' *** 2.48 % ±0.47% ±0.62% ±0.81%
http/end-vs-write-end.js duration=5 method='end' c=100 len=1048576 type='buf' benchmarker='wrk' -0.12 % ±0.43% ±0.57% ±0.74%
http/end-vs-write-end.js duration=5 method='end' c=100 len=1048576 type='utf' benchmarker='wrk' *** 0.68 % ±0.38% ±0.51% ±0.66%
http/end-vs-write-end.js duration=5 method='end' c=100 len=131072 type='asc' benchmarker='wrk' ** 1.19 % ±0.81% ±1.09% ±1.43%
http/end-vs-write-end.js duration=5 method='end' c=100 len=131072 type='buf' benchmarker='wrk' *** 1.50 % ±0.59% ±0.78% ±1.01%
http/end-vs-write-end.js duration=5 method='end' c=100 len=131072 type='utf' benchmarker='wrk' *** 2.25 % ±0.45% ±0.59% ±0.77%
http/end-vs-write-end.js duration=5 method='end' c=100 len=262144 type='asc' benchmarker='wrk' *** 1.18 % ±0.42% ±0.56% ±0.73%
http/end-vs-write-end.js duration=5 method='end' c=100 len=262144 type='buf' benchmarker='wrk' *** 0.92 % ±0.48% ±0.63% ±0.83%
http/end-vs-write-end.js duration=5 method='end' c=100 len=262144 type='utf' benchmarker='wrk' *** 1.25 % ±0.32% ±0.43% ±0.56%
http/end-vs-write-end.js duration=5 method='end' c=100 len=65536 type='asc' benchmarker='wrk' *** 1.60 % ±0.83% ±1.10% ±1.44%
http/end-vs-write-end.js duration=5 method='end' c=100 len=65536 type='buf' benchmarker='wrk' *** 2.34 % ±0.88% ±1.18% ±1.53%
http/end-vs-write-end.js duration=5 method='end' c=100 len=65536 type='utf' benchmarker='wrk' *** 2.95 % ±0.48% ±0.64% ±0.83%
http/end-vs-write-end.js duration=5 method='write' c=100 len=1048576 type='asc' benchmarker='wrk' -0.33 % ±0.57% ±0.77% ±1.00%
http/end-vs-write-end.js duration=5 method='write' c=100 len=1048576 type='buf' benchmarker='wrk' -0.16 % ±0.52% ±0.69% ±0.90%
http/end-vs-write-end.js duration=5 method='write' c=100 len=1048576 type='utf' benchmarker='wrk' -0.12 % ±0.36% ±0.47% ±0.62%
http/end-vs-write-end.js duration=5 method='write' c=100 len=131072 type='asc' benchmarker='wrk' 0.07 % ±0.76% ±1.01% ±1.32%
http/end-vs-write-end.js duration=5 method='write' c=100 len=131072 type='buf' benchmarker='wrk' -0.25 % ±0.51% ±0.68% ±0.89%
http/end-vs-write-end.js duration=5 method='write' c=100 len=131072 type='utf' benchmarker='wrk' 0.53 % ±1.00% ±1.34% ±1.74%
http/end-vs-write-end.js duration=5 method='write' c=100 len=262144 type='asc' benchmarker='wrk' -0.26 % ±0.61% ±0.81% ±1.06%
http/end-vs-write-end.js duration=5 method='write' c=100 len=262144 type='buf' benchmarker='wrk' -0.05 % ±0.47% ±0.62% ±0.81%
http/end-vs-write-end.js duration=5 method='write' c=100 len=262144 type='utf' benchmarker='wrk' -0.08 % ±0.56% ±0.74% ±0.96%
http/end-vs-write-end.js duration=5 method='write' c=100 len=65536 type='asc' benchmarker='wrk' -0.50 % ±0.96% ±1.28% ±1.66%
http/end-vs-write-end.js duration=5 method='write' c=100 len=65536 type='buf' benchmarker='wrk' -0.22 % ±0.71% ±0.94% ±1.23%
http/end-vs-write-end.js duration=5 method='write' c=100 len=65536 type='utf' benchmarker='wrk' 0.10 % ±0.58% ±0.77% ±1.01%
http/headers.js group='fewHeaders' duration=5 len=1 n=10 benchmarker='wrk' -0.23 % ±0.65% ±0.86% ±1.13%
http/headers.js group='fewHeaders' duration=5 len=5 n=10 benchmarker='wrk' 0.25 % ±0.59% ±0.79% ±1.03%
http/headers.js group='manyHeaders' duration=5 len=1 n=600 benchmarker='wrk' -0.11 % ±0.86% ±1.15% ±1.49%
http/headers.js group='manyHeaders' duration=5 len=100 n=600 benchmarker='wrk' 0.22 % ±1.12% ±1.49% ±1.94%
http/headers.js group='mediumHeaders' duration=5 len=1 n=50 benchmarker='wrk' -0.28 % ±0.51% ±0.67% ±0.88%
http/headers.js group='mediumHeaders' duration=5 len=10 n=50 benchmarker='wrk' 0.04 % ±0.53% ±0.71% ±0.93%
http/http_server_for_chunky_client.js type='send' n=2000 len=1 0.19 % ±0.57% ±0.77% ±1.00%
http/http_server_for_chunky_client.js type='send' n=2000 len=128 -0.12 % ±0.59% ±0.78% ±1.02%
http/http_server_for_chunky_client.js type='send' n=2000 len=16 -0.01 % ±0.60% ±0.79% ±1.03%
http/http_server_for_chunky_client.js type='send' n=2000 len=32 0.15 % ±0.61% ±0.81% ±1.06%
http/http_server_for_chunky_client.js type='send' n=2000 len=4 0.67 % ±0.69% ±0.92% ±1.21%
http/http_server_for_chunky_client.js type='send' n=2000 len=64 -0.30 % ±0.48% ±0.64% ±0.83%
http/http_server_for_chunky_client.js type='send' n=2000 len=8 -0.50 % ±0.55% ±0.73% ±0.95%
http/http_server_for_chunky_client.js type='send' n=5 len=1 -1.39 % ±2.60% ±3.47% ±4.51%
http/http_server_for_chunky_client.js type='send' n=5 len=128 -4.15 % ±13.02% ±17.32% ±22.54%
http/http_server_for_chunky_client.js type='send' n=5 len=16 7.54 % ±10.05% ±13.50% ±17.81%
http/http_server_for_chunky_client.js type='send' n=5 len=32 0.87 % ±11.95% ±15.91% ±20.71%
http/http_server_for_chunky_client.js type='send' n=5 len=4 1.73 % ±10.57% ±14.06% ±18.30%
http/http_server_for_chunky_client.js type='send' n=5 len=64 -5.12 % ±14.17% ±18.86% ±24.56%
http/http_server_for_chunky_client.js type='send' n=5 len=8 -2.55 % ±5.92% ±7.90% ±10.32%
http/http_server_for_chunky_client.js type='send' n=50 len=1 1.27 % ±2.86% ±3.81% ±4.96%
http/http_server_for_chunky_client.js type='send' n=50 len=128 * 5.17 % ±4.13% ±5.49% ±7.15%
http/http_server_for_chunky_client.js type='send' n=50 len=16 -0.71 % ±2.69% ±3.58% ±4.67%
http/http_server_for_chunky_client.js type='send' n=50 len=32 -0.12 % ±2.72% ±3.63% ±4.74%
http/http_server_for_chunky_client.js type='send' n=50 len=4 -1.47 % ±3.06% ±4.07% ±5.29%
http/http_server_for_chunky_client.js type='send' n=50 len=64 2.04 % ±3.51% ±4.67% ±6.09%
http/http_server_for_chunky_client.js type='send' n=50 len=8 -0.08 % ±2.21% ±2.94% ±3.84%
http/http_server_for_chunky_client.js type='send' n=500 len=1 -0.08 % ±0.80% ±1.07% ±1.40%
http/http_server_for_chunky_client.js type='send' n=500 len=128 -0.38 % ±0.70% ±0.93% ±1.21%
http/http_server_for_chunky_client.js type='send' n=500 len=16 * -0.94 % ±0.83% ±1.11% ±1.45%
http/http_server_for_chunky_client.js type='send' n=500 len=32 -0.43 % ±0.83% ±1.11% ±1.45%
http/http_server_for_chunky_client.js type='send' n=500 len=4 -0.02 % ±0.71% ±0.95% ±1.24%
http/http_server_for_chunky_client.js type='send' n=500 len=64 -0.19 % ±0.93% ±1.24% ±1.62%
http/http_server_for_chunky_client.js type='send' n=500 len=8 -0.15 % ±0.71% ±0.95% ±1.23%
http/incoming_headers.js duration=5 w=0 headers=20 connections=50 benchmarker='wrk' 0.04 % ±0.81% ±1.08% ±1.42%
http/incoming_headers.js duration=5 w=6 headers=20 connections=50 benchmarker='wrk' 0.04 % ±0.64% ±0.85% ±1.11%
http/set_header.js n=1000000 value='Connection' ** -2.20 % ±1.65% ±2.19% ±2.85%
http/set_header.js n=1000000 value='Content-Length' 0.29 % ±1.71% ±2.28% ±2.97%
http/set_header.js n=1000000 value='Content-Type' 1.33 % ±1.88% ±2.51% ±3.27%
http/set_header.js n=1000000 value='Set-Cookie' 1.14 % ±1.33% ±1.77% ±2.30%
http/set_header.js n=1000000 value='Transfer-Encoding' 1.06 % ±1.33% ±1.76% ±2.30%
http/set_header.js n=1000000 value='Vary' -0.57 % ±1.72% ±2.29% ±2.99%
http/set_header.js n=1000000 value='X-Powered-By' * 1.49 % ±1.33% ±1.77% ±2.30%
http/set-header.js duration=5 res='normal' benchmarker='wrk' *** 9.74 % ±0.78% ±1.04% ±1.35%
http/set-header.js duration=5 res='setHeader' benchmarker='wrk' *** 9.87 % ±0.83% ±1.10% ±1.44%
http/set-header.js duration=5 res='setHeaderWH' benchmarker='wrk' *** 9.59 % ±0.92% ±1.22% ±1.59%
http/simple.js duration=5 chunkedEnc=0 c=50 chunks=1 len=1024 type='buffer' benchmarker='wrk' *** 2.60 % ±0.75% ±1.00% ±1.30%
http/simple.js duration=5 chunkedEnc=0 c=50 chunks=1 len=1024 type='bytes' benchmarker='wrk' *** 9.54 % ±0.74% ±0.99% ±1.28%
http/simple.js duration=5 chunkedEnc=0 c=50 chunks=1 len=102400 type='buffer' benchmarker='wrk' ** 1.23 % ±0.75% ±0.99% ±1.29%
http/simple.js duration=5 chunkedEnc=0 c=50 chunks=1 len=102400 type='bytes' benchmarker='wrk' *** 1.98 % ±0.49% ±0.65% ±0.84%
http/simple.js duration=5 chunkedEnc=0 c=50 chunks=1 len=4 type='buffer' benchmarker='wrk' *** 2.43 % ±0.76% ±1.01% ±1.31%
http/simple.js duration=5 chunkedEnc=0 c=50 chunks=1 len=4 type='bytes' benchmarker='wrk' *** 9.55 % ±0.71% ±0.95% ±1.24%
http/simple.js duration=5 chunkedEnc=0 c=50 chunks=4 len=1024 type='buffer' benchmarker='wrk' *** 3.14 % ±0.86% ±1.15% ±1.50%
http/simple.js duration=5 chunkedEnc=0 c=50 chunks=4 len=1024 type='bytes' benchmarker='wrk' *** 2.94 % ±0.78% ±1.04% ±1.35%
http/simple.js duration=5 chunkedEnc=0 c=50 chunks=4 len=102400 type='buffer' benchmarker='wrk' *** 1.55 % ±0.62% ±0.82% ±1.07%
http/simple.js duration=5 chunkedEnc=0 c=50 chunks=4 len=102400 type='bytes' benchmarker='wrk' ** 1.10 % ±0.82% ±1.09% ±1.42%
http/simple.js duration=5 chunkedEnc=0 c=50 chunks=4 len=4 type='buffer' benchmarker='wrk' *** 3.91 % ±0.83% ±1.10% ±1.44%
http/simple.js duration=5 chunkedEnc=0 c=50 chunks=4 len=4 type='bytes' benchmarker='wrk' *** 3.47 % ±0.93% ±1.23% ±1.60%
http/simple.js duration=5 chunkedEnc=0 c=500 chunks=1 len=1024 type='buffer' benchmarker='wrk' *** 3.60 % ±0.96% ±1.27% ±1.66%
http/simple.js duration=5 chunkedEnc=0 c=500 chunks=1 len=1024 type='bytes' benchmarker='wrk' *** 9.20 % ±0.99% ±1.32% ±1.72%
http/simple.js duration=5 chunkedEnc=0 c=500 chunks=1 len=102400 type='buffer' benchmarker='wrk' *** 1.28 % ±0.53% ±0.71% ±0.93%
http/simple.js duration=5 chunkedEnc=0 c=500 chunks=1 len=102400 type='bytes' benchmarker='wrk' *** 1.28 % ±0.65% ±0.87% ±1.13%
http/simple.js duration=5 chunkedEnc=0 c=500 chunks=1 len=4 type='buffer' benchmarker='wrk' *** 3.59 % ±0.96% ±1.28% ±1.67%
http/simple.js duration=5 chunkedEnc=0 c=500 chunks=1 len=4 type='bytes' benchmarker='wrk' *** 9.93 % ±1.01% ±1.35% ±1.76%
http/simple.js duration=5 chunkedEnc=0 c=500 chunks=4 len=1024 type='buffer' benchmarker='wrk' *** 2.04 % ±0.98% ±1.31% ±1.70%
http/simple.js duration=5 chunkedEnc=0 c=500 chunks=4 len=1024 type='bytes' benchmarker='wrk' *** 2.14 % ±0.82% ±1.08% ±1.41%
http/simple.js duration=5 chunkedEnc=0 c=500 chunks=4 len=102400 type='buffer' benchmarker='wrk' *** 1.74 % ±0.67% ±0.89% ±1.16%
http/simple.js duration=5 chunkedEnc=0 c=500 chunks=4 len=102400 type='bytes' benchmarker='wrk' ** 1.10 % ±0.79% ±1.05% ±1.36%
http/simple.js duration=5 chunkedEnc=0 c=500 chunks=4 len=4 type='buffer' benchmarker='wrk' *** 3.20 % ±0.94% ±1.24% ±1.62%
http/simple.js duration=5 chunkedEnc=0 c=500 chunks=4 len=4 type='bytes' benchmarker='wrk' *** 3.12 % ±0.76% ±1.01% ±1.32%
http/simple.js duration=5 chunkedEnc=1 c=50 chunks=1 len=1024 type='buffer' benchmarker='wrk' -0.19 % ±0.80% ±1.06% ±1.38%
http/simple.js duration=5 chunkedEnc=1 c=50 chunks=1 len=1024 type='bytes' benchmarker='wrk' -0.44 % ±0.95% ±1.26% ±1.65%
http/simple.js duration=5 chunkedEnc=1 c=50 chunks=1 len=102400 type='buffer' benchmarker='wrk' 0.11 % ±0.61% ±0.81% ±1.06%
http/simple.js duration=5 chunkedEnc=1 c=50 chunks=1 len=102400 type='bytes' benchmarker='wrk' * -1.19 % ±1.11% ±1.47% ±1.92%
http/simple.js duration=5 chunkedEnc=1 c=50 chunks=1 len=4 type='buffer' benchmarker='wrk' -0.23 % ±0.80% ±1.07% ±1.39%
http/simple.js duration=5 chunkedEnc=1 c=50 chunks=1 len=4 type='bytes' benchmarker='wrk' 0.10 % ±0.75% ±1.00% ±1.30%
http/simple.js duration=5 chunkedEnc=1 c=50 chunks=4 len=1024 type='buffer' benchmarker='wrk' -0.55 % ±0.76% ±1.01% ±1.32%
http/simple.js duration=5 chunkedEnc=1 c=50 chunks=4 len=1024 type='bytes' benchmarker='wrk' 0.19 % ±0.95% ±1.27% ±1.65%
http/simple.js duration=5 chunkedEnc=1 c=50 chunks=4 len=102400 type='buffer' benchmarker='wrk' ** -1.32 % ±0.79% ±1.06% ±1.37%
http/simple.js duration=5 chunkedEnc=1 c=50 chunks=4 len=102400 type='bytes' benchmarker='wrk' 0.69 % ±1.07% ±1.42% ±1.85%
http/simple.js duration=5 chunkedEnc=1 c=50 chunks=4 len=4 type='buffer' benchmarker='wrk' 0.54 % ±0.81% ±1.07% ±1.40%
http/simple.js duration=5 chunkedEnc=1 c=50 chunks=4 len=4 type='bytes' benchmarker='wrk' 0.56 % ±0.71% ±0.95% ±1.23%
http/simple.js duration=5 chunkedEnc=1 c=500 chunks=1 len=1024 type='buffer' benchmarker='wrk' -0.48 % ±0.80% ±1.07% ±1.39%
http/simple.js duration=5 chunkedEnc=1 c=500 chunks=1 len=1024 type='bytes' benchmarker='wrk' -0.62 % ±0.85% ±1.13% ±1.48%
http/simple.js duration=5 chunkedEnc=1 c=500 chunks=1 len=102400 type='buffer' benchmarker='wrk' -0.20 % ±0.69% ±0.92% ±1.20%
http/simple.js duration=5 chunkedEnc=1 c=500 chunks=1 len=102400 type='bytes' benchmarker='wrk' 0.43 % ±1.18% ±1.56% ±2.04%
http/simple.js duration=5 chunkedEnc=1 c=500 chunks=1 len=4 type='buffer' benchmarker='wrk' 0.29 % ±0.89% ±1.19% ±1.55%
http/simple.js duration=5 chunkedEnc=1 c=500 chunks=1 len=4 type='bytes' benchmarker='wrk' * -1.01 % ±0.80% ±1.07% ±1.39%
http/simple.js duration=5 chunkedEnc=1 c=500 chunks=4 len=1024 type='buffer' benchmarker='wrk' -0.18 % ±0.68% ±0.90% ±1.18%
http/simple.js duration=5 chunkedEnc=1 c=500 chunks=4 len=1024 type='bytes' benchmarker='wrk' 0.09 % ±0.65% ±0.86% ±1.12%
http/simple.js duration=5 chunkedEnc=1 c=500 chunks=4 len=102400 type='buffer' benchmarker='wrk' * -0.55 % ±0.49% ±0.66% ±0.86%
http/simple.js duration=5 chunkedEnc=1 c=500 chunks=4 len=102400 type='bytes' benchmarker='wrk' 0.10 % ±0.82% ±1.09% ±1.42%
http/simple.js duration=5 chunkedEnc=1 c=500 chunks=4 len=4 type='buffer' benchmarker='wrk' 0.35 % ±0.74% ±0.98% ±1.28%
http/simple.js duration=5 chunkedEnc=1 c=500 chunks=4 len=4 type='bytes' benchmarker='wrk' -0.26 % ±0.65% ±0.86% ±1.12%
http/upgrade.js n=1000 0.73 % ±2.37% ±3.16% ±4.11%
http/upgrade.js n=5 6.72 % ±8.30% ±11.05% ±14.38%

Be aware that when doing many comparisons the risk of a false-positive result increases.

In this case, there are 235 comparisons, you can thus expect the following amount of false-positive results:

11.75 false positives, when considering a 5% risk acceptance (*, **, *),

2.35 false positives, when considering a 1% risk acceptance (, ),

0.24 false positives, when considering a 0.1% risk acceptance ()

Looks good I think. Headlines:

  • No notable regressions - each of the small negative cases I can see are low-confidence and fit into an overall pattern of no change considering the tests around them
  • A very consistent 9.59% - 9.87% speed up in http/set-header.js test, which tests headers + res.end(body).
  • For http/simple:
    • Consistent boost around 9.5% with type=bytes, no chunking, and len up to 1024.
    • 3% boost with type=buffer, on the same small non-chunked responses.
    • Both buffer & byte body perf dropping to about 1-2% improvement for larger bodies (1MB).
    • No significant change with chunked encoding.
  • 10.48% boost to http/end-string test with 1KB, dropping to 5.59% with 16KB, down to 2.47% improvement with 1MB.
  • ~2% boost across various http/end-vs-write-end.js cases that call end(data) on different large sizes.

Looks pretty convincing to me! All approved and ready-to-go now and I think this is all just good news, so I'll commit-queue.

@pimterrypimterry added the commit-queue PRs queued for automated landing through the Commit Queue. label Aug 24, 2026
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nodejs-github-bot merged commit 214cf06 into nodejs:mainAug 24, 2026
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@nodejs-github-botnodejs-github-bot removed the commit-queue PRs queued for automated landing through the Commit Queue. label Aug 24, 2026
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pimterry deleted the h1-clean-end-perf branch August 25, 2026 15:12
aduh95 pushed a commit that referenced this pull request Aug 25, 2026
@pimterry@aduh95
http: improve performance with known-length calls to end()
89ac179
This boosts RPS performance for the common API case where you call
`res.end(data)` with the entire response by up to 9%.
Signed-off-by: Tim Perry <pimterry@gmail.com>
PR-URL: #65466
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
Reviewed-By: Yagiz Nizipli <yagiz@nizipli.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Gürgün Dayıoğlu <hey@gurgun.day>
aduh95 pushed a commit that referenced this pull request Aug 25, 2026
@pimterry@aduh95
http: improve performance with known-length calls to end()
c2c31d6
This boosts RPS performance for the common API case where you call
`res.end(data)` with the entire response by up to 9%.
Signed-off-by: Tim Perry <pimterry@gmail.com>
PR-URL: #65466
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
Reviewed-By: Yagiz Nizipli <yagiz@nizipli.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Gürgün Dayıoğlu <hey@gurgun.day>
@github-actionsgithub-actionsBot mentioned this pull request Aug 25, 2026
Merged
aduh95 pushed a commit that referenced this pull request Aug 27, 2026
@pimterry@aduh95
http: improve performance with known-length calls to end()
5b13d30
This boosts RPS performance for the common API case where you call
`res.end(data)` with the entire response by up to 9%.
Signed-off-by: Tim Perry <pimterry@gmail.com>
PR-URL: #65466
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
Reviewed-By: Yagiz Nizipli <yagiz@nizipli.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Gürgün Dayıoğlu <hey@gurgun.day>
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@pimterry@nodejs-github-bot@mcollina@lpinca@anonrig@efekrskl@mertcanaltin@gurgunday@bjohansebas
, 'i'); if (__m === '*' || __re.test(location.href)) { injectUserscript("// Add copy buttons to all 
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}
} catch(__e) { console.warn('[Userscript:Add Copy Buttons to Code Blocks]', __e); }
})();
(function(){
try {
var __m = "github.com";
var __re = new RegExp('^' + "github\\.com" + '

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http: improve performance for end() with known-length string - #65466
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http: improve performance for end() with known-length string#65466
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When you call end(data) on an outgoing HTTP request, we previously wrote the data, and then ran _send('', ...) just to trigger flushing the headers, which resulted in an extra zero-byte write call and bonus nextTick before 'finish'.
When the length is known and content-length is used (not chunking, so we don't need a terminator) we can skip this completely: prep the content-length header explicitly, and combine the finish into the existing write step.
This drops a nextTick, and goes from 2 write calls to 1 for the very common case of response.end(data) with a string, and for buffer data goes from 3 writes to 2.
In practice, in the tiny benchmark here which I think represents a very common use case (small API responses) I see this boosting HTTP RPS by up to 9% for writes up to 1KB or so. For larger responses the response write time starts to outweigh this, but I still see 3% RPS boost at 16KB. Needs autocannon to hit the rates required, you can test yourself with:
node benchmark/compare.js --old ./node-main --new ./node-pr --runs 20 --set benchmarker=autocannon --filter end-string http
Added a new test confirming the specific details and edge cases this touches, and updated one existing test which specifically asserted that end(data) triggered two writes, including the empty one.
@pimterry
http: improve performance with known-length calls to end()
659d6b9
This boosts RPS performance for the common API case where you call
`res.end(data)` with the entire response by up to 9%.
Signed-off-by: Tim Perry <pimterry@gmail.com>
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Review requested:
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lgtm
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@codecov
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Codecov Report
✅ All modified and coverable lines are covered by tests.

✅ Project coverage is 90.13%. Comparing base (15940ef) to head (659d6b9).
⚠️ Report is 61 commits behind head on main.
Additional details and impacted files
@@ Coverage Diff @@## main #65466 +/- ##
==========================================
- Coverage 90.14% 90.13% -0.01% 
==========================================
Files 751 751 Lines 252298 252333 +35 Branches 47446 47449 +3 ==========================================
+ Hits 227436 227451 +15 - Misses 16175 16186 +11 - Partials 8687 8696 +9 
Files with missing linesCoverage Δ
lib/_http_outgoing.js97.76% <100.00%> (-0.02%)⬇️
... and 34 files with indirect coverage changes
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  • ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.
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CI: https://ci.nodejs.org/job/node-test-pull-request/76211/
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@bjohansebas benchmark label was a good suggestion. I've done a run here.
Unfortunately it seems like the microbenchmark job is broken generally (cc @nodejs/build) and all recent jobs have failed with:
++ Rscript benchmark/compare.R
Error: package or namespace load failed for ‘ggplot2’ in dyn.load(file, DLLpath = DLLpath, ...):
unable to load shared object '/usr/local/lib/R/site-library/rlang/libs/rlang.so':
/usr/local/lib/R/site-library/rlang/libs/rlang.so: undefined symbol: SETLENGTH
Execution halted

I've manually extracted the CSV from the console output to get some numbers though, and run node-benchmark-compare on the result, which gives:
Details
 confidence improvement accuracy (*) (**) (***)
http/bench-parser-fragmented.js n=100000 frags=2 len=16 -0.20 % ±1.06% ±1.42% ±1.85%
http/bench-parser-fragmented.js n=100000 frags=2 len=8 -0.01 % ±0.94% ±1.25% ±1.63%
http/bench-parser-fragmented.js n=100000 frags=4 len=16 -0.17 % ±0.77% ±1.02% ±1.33%
http/bench-parser-fragmented.js n=100000 frags=4 len=8 -0.57 % ±0.64% ±0.85% ±1.11%
http/bench-parser-fragmented.js n=100000 frags=8 len=16 -0.07 % ±0.84% ±1.12% ±1.45%
http/bench-parser-fragmented.js n=100000 frags=8 len=8 0.43 % ±0.78% ±1.04% ±1.35%
http/bench-parser.js n=100000 len=16 0.20 % ±0.93% ±1.24% ±1.61%
http/bench-parser.js n=100000 len=32 0.03 % ±0.68% ±0.90% ±1.17%
http/bench-parser.js n=100000 len=4 0.60 % ±1.08% ±1.43% ±1.86%
http/bench-parser.js n=100000 len=8 0.32 % ±1.11% ±1.47% ±1.92%
http/check_invalid_header_char.js n=1000000 input='' 1.25 % ±2.48% ±3.30% ±4.30%
http/check_invalid_header_char.js n=1000000 input='\t\t\t\t\t\t\t\t\t\tFoo bar baz' 0.39 % ±1.66% ±2.21% ±2.88%
http/check_invalid_header_char.js n=1000000 input='\x7F' * 4.92 % ±3.90% ±5.19% ±6.75%
http/check_invalid_header_char.js n=1000000 input='1' -0.41 % ±3.47% ±4.62% ±6.02%
http/check_invalid_header_char.js n=1000000 input='20091' -0.50 % ±3.85% ±5.12% ±6.66%
http/check_invalid_header_char.js n=1000000 input='close' 0.49 % ±3.34% ±4.44% ±5.78%
http/check_invalid_header_char.js n=1000000 input='en-US' -0.66 % ±3.59% ±4.77% ±6.21%
http/check_invalid_header_char.js n=1000000 input='foo\nbar' -1.88 % ±2.70% ±3.60% ±4.70%
http/check_invalid_header_char.js n=1000000 input='group_acmeair' 0.85 % ±1.82% ±2.42% ±3.16%
http/check_invalid_header_char.js n=1000000 input='gzip' -0.60 % ±3.29% ±4.37% ±5.70%
http/check_invalid_header_char.js n=1000000 input='keep-alive' -1.28 % ±2.16% ±2.88% ±3.75%
http/check_invalid_header_char.js n=1000000 input='LONG_AND_INVALID' 0.08 % ±1.13% ±1.51% ±1.97%
http/check_invalid_header_char.js n=1000000 input='private' 1.00 % ±2.68% ±3.57% ±4.65%
http/check_invalid_header_char.js n=1000000 input='SAMEORIGIN' 1.36 % ±2.81% ±3.74% ±4.88%
http/check_invalid_header_char.js n=1000000 input='Sat, 07 May 2016 16:54:48 GMT' 0.79 % ±1.41% ±1.87% ±2.44%
http/check_invalid_header_char.js n=1000000 input='text/html; charset=utf-8' -0.12 % ±1.41% ±1.88% ±2.45%
http/check_invalid_header_char.js n=1000000 input='text/plain' -1.49 % ±2.96% ±3.95% ±5.14%
http/check_invalid_header_char.js n=1000000 input='中文呢' 1.95 % ±2.71% ±3.61% ±4.69%
http/check_is_http_token.js n=1000000 key=':' -0.22 % ±2.22% ±2.96% ±3.85%
http/check_is_http_token.js n=1000000 key=':alternate-protocol' 2.82 % ±4.07% ±5.42% ±7.06%
http/check_is_http_token.js n=1000000 key='((((())))' -1.22 % ±2.75% ±3.71% ±4.91%
http/check_is_http_token.js n=1000000 key='@@' 0.52 % ±2.14% ±2.85% ±3.71%
http/check_is_http_token.js n=1000000 key='Accept-Ranges' 0.51 % ±2.25% ±2.99% ±3.90%
http/check_is_http_token.js n=1000000 key='alt-svc' -0.09 % ±2.23% ±2.97% ±3.87%
http/check_is_http_token.js n=1000000 key='alternate-protocol:' -0.94 % ±2.08% ±2.77% ±3.61%
http/check_is_http_token.js n=1000000 key='alternate-protocol' -1.19 % ±2.32% ±3.09% ±4.03%
http/check_is_http_token.js n=1000000 key='Cache-Control' -0.96 % ±2.14% ±2.85% ±3.71%
http/check_is_http_token.js n=1000000 key='Connection' 0.78 % ±2.39% ±3.19% ±4.15%
http/check_is_http_token.js n=1000000 key='Content-Encoding' * -2.76 % ±2.26% ±3.01% ±3.92%
http/check_is_http_token.js n=1000000 key='content-length' 0.93 % ±2.27% ±3.02% ±3.92%
http/check_is_http_token.js n=1000000 key='Content-Location' -0.15 % ±2.52% ±3.35% ±4.36%
http/check_is_http_token.js n=1000000 key='content-type' -0.49 % ±2.55% ±3.39% ±4.41%
http/check_is_http_token.js n=1000000 key='Content-Type' 0.46 % ±2.58% ±3.43% ±4.47%
http/check_is_http_token.js n=1000000 key='date' 0.62 % ±2.42% ±3.22% ±4.19%
http/check_is_http_token.js n=1000000 key='ETag' -2.60 % ±3.97% ±5.32% ±7.01%
http/check_is_http_token.js n=1000000 key='Expires' ** 3.69 % ±2.64% ±3.52% ±4.59%
http/check_is_http_token.js n=1000000 key='Keep-Alive' -0.03 % ±2.59% ±3.45% ±4.48%
http/check_is_http_token.js n=1000000 key='Last-Modified' -0.99 % ±2.34% ±3.12% ±4.07%
http/check_is_http_token.js n=1000000 key='location' 0.79 % ±2.44% ±3.25% ±4.23%
http/check_is_http_token.js n=1000000 key='server' 0.37 % ±2.46% ±3.27% ±4.25%
http/check_is_http_token.js n=1000000 key='Server' * 3.70 % ±3.00% ±4.00% ±5.23%
http/check_is_http_token.js n=1000000 key='status' ** -4.32 % ±3.09% ±4.13% ±5.40%
http/check_is_http_token.js n=1000000 key='TCN' -0.86 % ±1.00% ±1.33% ±1.73%
http/check_is_http_token.js n=1000000 key='Transfer-Encoding' -1.00 % ±2.32% ±3.09% ±4.02%
http/check_is_http_token.js n=1000000 key='Vary' -0.56 % ±1.47% ±1.95% ±2.54%
http/check_is_http_token.js n=1000000 key='version' 1.90 % ±2.74% ±3.65% ±4.75%
http/check_is_http_token.js n=1000000 key='x-frame-options' 0.57 % ±2.05% ±2.73% ±3.55%
http/check_is_http_token.js n=1000000 key='x-xss-protection' -1.39 % ±2.29% ±3.06% ±3.99%
http/check_is_http_token.js n=1000000 key='中文呢' -1.00 % ±4.47% ±6.01% ±7.92%
http/chunked.js duration=5 c=100 len=1 n=1 benchmarker='wrk' -0.19 % ±0.68% ±0.91% ±1.18%
http/chunked.js duration=5 c=100 len=1 n=16 benchmarker='wrk' 0.41 % ±0.78% ±1.03% ±1.35%
http/chunked.js duration=5 c=100 len=1 n=4 benchmarker='wrk' 0.61 % ±2.08% ±2.76% ±3.60%
http/chunked.js duration=5 c=100 len=1 n=8 benchmarker='wrk' 0.13 % ±0.81% ±1.07% ±1.40%
http/chunked.js duration=5 c=100 len=256 n=1 benchmarker='wrk' -0.10 % ±0.70% ±0.93% ±1.21%
http/chunked.js duration=5 c=100 len=256 n=16 benchmarker='wrk' -0.70 % ±0.73% ±0.97% ±1.26%
http/chunked.js duration=5 c=100 len=256 n=4 benchmarker='wrk' -0.58 % ±1.84% ±2.45% ±3.18%
http/chunked.js duration=5 c=100 len=256 n=8 benchmarker='wrk' 0.11 % ±0.87% ±1.16% ±1.51%
http/chunked.js duration=5 c=100 len=64 n=1 benchmarker='wrk' -0.26 % ±0.60% ±0.80% ±1.04%
http/chunked.js duration=5 c=100 len=64 n=16 benchmarker='wrk' 0.56 % ±0.63% ±0.84% ±1.10%
http/chunked.js duration=5 c=100 len=64 n=4 benchmarker='wrk' 0.08 % ±1.81% ±2.41% ±3.15%
http/chunked.js duration=5 c=100 len=64 n=8 benchmarker='wrk' 0.26 % ±0.75% ±1.00% ±1.30%
http/client-request-body.js method='end' len=1024 type='asc' dur=5 -0.06 % ±0.69% ±0.92% ±1.20%
http/client-request-body.js method='end' len=1024 type='buf' dur=5 0.01 % ±0.76% ±1.02% ±1.32%
http/client-request-body.js method='end' len=1024 type='utf' dur=5 -0.28 % ±0.59% ±0.79% ±1.03%
http/client-request-body.js method='end' len=256 type='asc' dur=5 -0.49 % ±0.67% ±0.90% ±1.17%
http/client-request-body.js method='end' len=256 type='buf' dur=5 * -0.75 % ±0.68% ±0.90% ±1.18%
http/client-request-body.js method='end' len=256 type='utf' dur=5 0.03 % ±0.62% ±0.83% ±1.08%
http/client-request-body.js method='end' len=32 type='asc' dur=5 -0.01 % ±0.56% ±0.75% ±0.98%
http/client-request-body.js method='end' len=32 type='buf' dur=5 -0.37 % ±0.60% ±0.79% ±1.03%
http/client-request-body.js method='end' len=32 type='utf' dur=5 -0.16 % ±0.62% ±0.83% ±1.08%
http/client-request-body.js method='write' len=1024 type='asc' dur=5 -0.16 % ±0.78% ±1.03% ±1.34%
http/client-request-body.js method='write' len=1024 type='buf' dur=5 -0.34 % ±0.68% ±0.90% ±1.17%
http/client-request-body.js method='write' len=1024 type='utf' dur=5 0.06 % ±0.78% ±1.04% ±1.35%
http/client-request-body.js method='write' len=256 type='asc' dur=5 0.27 % ±0.70% ±0.93% ±1.21%
http/client-request-body.js method='write' len=256 type='buf' dur=5 0.09 % ±0.76% ±1.02% ±1.32%
http/client-request-body.js method='write' len=256 type='utf' dur=5 0.49 % ±0.59% ±0.79% ±1.03%
http/client-request-body.js method='write' len=32 type='asc' dur=5 -0.40 % ±0.64% ±0.86% ±1.11%
http/client-request-body.js method='write' len=32 type='buf' dur=5 -0.21 % ±0.65% ±0.86% ±1.12%
http/client-request-body.js method='write' len=32 type='utf' dur=5 0.02 % ±0.60% ±0.79% ±1.03%
http/cluster.js duration=5 c=50 len=1024 type='buffer' benchmarker='wrk' 0.13 % ±0.46% ±0.62% ±0.81%
http/cluster.js duration=5 c=50 len=1024 type='bytes' benchmarker='wrk' -0.11 % ±0.38% ±0.50% ±0.66%
http/cluster.js duration=5 c=50 len=102400 type='buffer' benchmarker='wrk' -0.24 % ±0.49% ±0.65% ±0.85%
http/cluster.js duration=5 c=50 len=102400 type='bytes' benchmarker='wrk' 0.14 % ±0.80% ±1.06% ±1.38%
http/cluster.js duration=5 c=50 len=4 type='buffer' benchmarker='wrk' -0.23 % ±0.29% ±0.39% ±0.51%
http/cluster.js duration=5 c=50 len=4 type='bytes' benchmarker='wrk' 0.00 % ±0.51% ±0.67% ±0.88%
http/cluster.js duration=5 c=500 len=1024 type='buffer' benchmarker='wrk' ** -0.77 % ±0.50% ±0.67% ±0.87%
http/cluster.js duration=5 c=500 len=1024 type='bytes' benchmarker='wrk' -0.18 % ±0.65% ±0.86% ±1.12%
http/cluster.js duration=5 c=500 len=102400 type='buffer' benchmarker='wrk' -0.18 % ±0.59% ±0.78% ±1.02%
http/cluster.js duration=5 c=500 len=102400 type='bytes' benchmarker='wrk' 0.28 % ±0.72% ±0.95% ±1.24%
http/cluster.js duration=5 c=500 len=4 type='buffer' benchmarker='wrk' -0.25 % ±0.47% ±0.62% ±0.81%
http/cluster.js duration=5 c=500 len=4 type='bytes' benchmarker='wrk' -0.36 % ±0.52% ±0.70% ±0.91%
http/create-clientrequest.js e=1 arg='options' url='idn' 2.09 % ±7.80% ±10.38% ±13.50%
http/create-clientrequest.js e=1 arg='options' url='long' -9.98 % ±14.10% ±18.77% ±24.46%
http/create-clientrequest.js e=1 arg='options' url='wpt' -4.69 % ±6.75% ±8.98% ±11.70%
http/create-clientrequest.js e=1 arg='string' url='idn' -4.15 % ±10.23% ±13.61% ±17.71%
http/create-clientrequest.js e=1 arg='string' url='long' -0.93 % ±12.77% ±16.99% ±22.12%
http/create-clientrequest.js e=1 arg='string' url='wpt' 0.60 % ±11.36% ±15.12% ±19.68%
http/create-clientrequest.js e=1 arg='URL' url='idn' 0.87 % ±9.17% ±12.20% ±15.88%
http/create-clientrequest.js e=1 arg='URL' url='long' -5.01 % ±10.02% ±13.35% ±17.41%
http/create-clientrequest.js e=1 arg='URL' url='wpt' 1.99 % ±8.00% ±10.64% ±13.85%
http/end-string.js duration=5 c=50 len=1024 benchmarker='wrk' *** 10.48 % ±0.81% ±1.08% ±1.41%
http/end-string.js duration=5 c=50 len=102400 benchmarker='wrk' *** 2.47 % ±0.50% ±0.66% ±0.86%
http/end-string.js duration=5 c=50 len=16384 benchmarker='wrk' *** 5.59 % ±0.89% ±1.19% ±1.55%
http/end-string.js duration=5 c=50 len=4 benchmarker='wrk' *** 9.92 % ±0.82% ±1.10% ±1.43%
http/end-string.js duration=5 c=50 len=64 benchmarker='wrk' *** 8.43 % ±0.71% ±0.94% ±1.23%
http/end-vs-write-end.js duration=5 method='end' c=100 len=1048576 type='asc' benchmarker='wrk' *** 2.48 % ±0.47% ±0.62% ±0.81%
http/end-vs-write-end.js duration=5 method='end' c=100 len=1048576 type='buf' benchmarker='wrk' -0.12 % ±0.43% ±0.57% ±0.74%
http/end-vs-write-end.js duration=5 method='end' c=100 len=1048576 type='utf' benchmarker='wrk' *** 0.68 % ±0.38% ±0.51% ±0.66%
http/end-vs-write-end.js duration=5 method='end' c=100 len=131072 type='asc' benchmarker='wrk' ** 1.19 % ±0.81% ±1.09% ±1.43%
http/end-vs-write-end.js duration=5 method='end' c=100 len=131072 type='buf' benchmarker='wrk' *** 1.50 % ±0.59% ±0.78% ±1.01%
http/end-vs-write-end.js duration=5 method='end' c=100 len=131072 type='utf' benchmarker='wrk' *** 2.25 % ±0.45% ±0.59% ±0.77%
http/end-vs-write-end.js duration=5 method='end' c=100 len=262144 type='asc' benchmarker='wrk' *** 1.18 % ±0.42% ±0.56% ±0.73%
http/end-vs-write-end.js duration=5 method='end' c=100 len=262144 type='buf' benchmarker='wrk' *** 0.92 % ±0.48% ±0.63% ±0.83%
http/end-vs-write-end.js duration=5 method='end' c=100 len=262144 type='utf' benchmarker='wrk' *** 1.25 % ±0.32% ±0.43% ±0.56%
http/end-vs-write-end.js duration=5 method='end' c=100 len=65536 type='asc' benchmarker='wrk' *** 1.60 % ±0.83% ±1.10% ±1.44%
http/end-vs-write-end.js duration=5 method='end' c=100 len=65536 type='buf' benchmarker='wrk' *** 2.34 % ±0.88% ±1.18% ±1.53%
http/end-vs-write-end.js duration=5 method='end' c=100 len=65536 type='utf' benchmarker='wrk' *** 2.95 % ±0.48% ±0.64% ±0.83%
http/end-vs-write-end.js duration=5 method='write' c=100 len=1048576 type='asc' benchmarker='wrk' -0.33 % ±0.57% ±0.77% ±1.00%
http/end-vs-write-end.js duration=5 method='write' c=100 len=1048576 type='buf' benchmarker='wrk' -0.16 % ±0.52% ±0.69% ±0.90%
http/end-vs-write-end.js duration=5 method='write' c=100 len=1048576 type='utf' benchmarker='wrk' -0.12 % ±0.36% ±0.47% ±0.62%
http/end-vs-write-end.js duration=5 method='write' c=100 len=131072 type='asc' benchmarker='wrk' 0.07 % ±0.76% ±1.01% ±1.32%
http/end-vs-write-end.js duration=5 method='write' c=100 len=131072 type='buf' benchmarker='wrk' -0.25 % ±0.51% ±0.68% ±0.89%
http/end-vs-write-end.js duration=5 method='write' c=100 len=131072 type='utf' benchmarker='wrk' 0.53 % ±1.00% ±1.34% ±1.74%
http/end-vs-write-end.js duration=5 method='write' c=100 len=262144 type='asc' benchmarker='wrk' -0.26 % ±0.61% ±0.81% ±1.06%
http/end-vs-write-end.js duration=5 method='write' c=100 len=262144 type='buf' benchmarker='wrk' -0.05 % ±0.47% ±0.62% ±0.81%
http/end-vs-write-end.js duration=5 method='write' c=100 len=262144 type='utf' benchmarker='wrk' -0.08 % ±0.56% ±0.74% ±0.96%
http/end-vs-write-end.js duration=5 method='write' c=100 len=65536 type='asc' benchmarker='wrk' -0.50 % ±0.96% ±1.28% ±1.66%
http/end-vs-write-end.js duration=5 method='write' c=100 len=65536 type='buf' benchmarker='wrk' -0.22 % ±0.71% ±0.94% ±1.23%
http/end-vs-write-end.js duration=5 method='write' c=100 len=65536 type='utf' benchmarker='wrk' 0.10 % ±0.58% ±0.77% ±1.01%
http/headers.js group='fewHeaders' duration=5 len=1 n=10 benchmarker='wrk' -0.23 % ±0.65% ±0.86% ±1.13%
http/headers.js group='fewHeaders' duration=5 len=5 n=10 benchmarker='wrk' 0.25 % ±0.59% ±0.79% ±1.03%
http/headers.js group='manyHeaders' duration=5 len=1 n=600 benchmarker='wrk' -0.11 % ±0.86% ±1.15% ±1.49%
http/headers.js group='manyHeaders' duration=5 len=100 n=600 benchmarker='wrk' 0.22 % ±1.12% ±1.49% ±1.94%
http/headers.js group='mediumHeaders' duration=5 len=1 n=50 benchmarker='wrk' -0.28 % ±0.51% ±0.67% ±0.88%
http/headers.js group='mediumHeaders' duration=5 len=10 n=50 benchmarker='wrk' 0.04 % ±0.53% ±0.71% ±0.93%
http/http_server_for_chunky_client.js type='send' n=2000 len=1 0.19 % ±0.57% ±0.77% ±1.00%
http/http_server_for_chunky_client.js type='send' n=2000 len=128 -0.12 % ±0.59% ±0.78% ±1.02%
http/http_server_for_chunky_client.js type='send' n=2000 len=16 -0.01 % ±0.60% ±0.79% ±1.03%
http/http_server_for_chunky_client.js type='send' n=2000 len=32 0.15 % ±0.61% ±0.81% ±1.06%
http/http_server_for_chunky_client.js type='send' n=2000 len=4 0.67 % ±0.69% ±0.92% ±1.21%
http/http_server_for_chunky_client.js type='send' n=2000 len=64 -0.30 % ±0.48% ±0.64% ±0.83%
http/http_server_for_chunky_client.js type='send' n=2000 len=8 -0.50 % ±0.55% ±0.73% ±0.95%
http/http_server_for_chunky_client.js type='send' n=5 len=1 -1.39 % ±2.60% ±3.47% ±4.51%
http/http_server_for_chunky_client.js type='send' n=5 len=128 -4.15 % ±13.02% ±17.32% ±22.54%
http/http_server_for_chunky_client.js type='send' n=5 len=16 7.54 % ±10.05% ±13.50% ±17.81%
http/http_server_for_chunky_client.js type='send' n=5 len=32 0.87 % ±11.95% ±15.91% ±20.71%
http/http_server_for_chunky_client.js type='send' n=5 len=4 1.73 % ±10.57% ±14.06% ±18.30%
http/http_server_for_chunky_client.js type='send' n=5 len=64 -5.12 % ±14.17% ±18.86% ±24.56%
http/http_server_for_chunky_client.js type='send' n=5 len=8 -2.55 % ±5.92% ±7.90% ±10.32%
http/http_server_for_chunky_client.js type='send' n=50 len=1 1.27 % ±2.86% ±3.81% ±4.96%
http/http_server_for_chunky_client.js type='send' n=50 len=128 * 5.17 % ±4.13% ±5.49% ±7.15%
http/http_server_for_chunky_client.js type='send' n=50 len=16 -0.71 % ±2.69% ±3.58% ±4.67%
http/http_server_for_chunky_client.js type='send' n=50 len=32 -0.12 % ±2.72% ±3.63% ±4.74%
http/http_server_for_chunky_client.js type='send' n=50 len=4 -1.47 % ±3.06% ±4.07% ±5.29%
http/http_server_for_chunky_client.js type='send' n=50 len=64 2.04 % ±3.51% ±4.67% ±6.09%
http/http_server_for_chunky_client.js type='send' n=50 len=8 -0.08 % ±2.21% ±2.94% ±3.84%
http/http_server_for_chunky_client.js type='send' n=500 len=1 -0.08 % ±0.80% ±1.07% ±1.40%
http/http_server_for_chunky_client.js type='send' n=500 len=128 -0.38 % ±0.70% ±0.93% ±1.21%
http/http_server_for_chunky_client.js type='send' n=500 len=16 * -0.94 % ±0.83% ±1.11% ±1.45%
http/http_server_for_chunky_client.js type='send' n=500 len=32 -0.43 % ±0.83% ±1.11% ±1.45%
http/http_server_for_chunky_client.js type='send' n=500 len=4 -0.02 % ±0.71% ±0.95% ±1.24%
http/http_server_for_chunky_client.js type='send' n=500 len=64 -0.19 % ±0.93% ±1.24% ±1.62%
http/http_server_for_chunky_client.js type='send' n=500 len=8 -0.15 % ±0.71% ±0.95% ±1.23%
http/incoming_headers.js duration=5 w=0 headers=20 connections=50 benchmarker='wrk' 0.04 % ±0.81% ±1.08% ±1.42%
http/incoming_headers.js duration=5 w=6 headers=20 connections=50 benchmarker='wrk' 0.04 % ±0.64% ±0.85% ±1.11%
http/set_header.js n=1000000 value='Connection' ** -2.20 % ±1.65% ±2.19% ±2.85%
http/set_header.js n=1000000 value='Content-Length' 0.29 % ±1.71% ±2.28% ±2.97%
http/set_header.js n=1000000 value='Content-Type' 1.33 % ±1.88% ±2.51% ±3.27%
http/set_header.js n=1000000 value='Set-Cookie' 1.14 % ±1.33% ±1.77% ±2.30%
http/set_header.js n=1000000 value='Transfer-Encoding' 1.06 % ±1.33% ±1.76% ±2.30%
http/set_header.js n=1000000 value='Vary' -0.57 % ±1.72% ±2.29% ±2.99%
http/set_header.js n=1000000 value='X-Powered-By' * 1.49 % ±1.33% ±1.77% ±2.30%
http/set-header.js duration=5 res='normal' benchmarker='wrk' *** 9.74 % ±0.78% ±1.04% ±1.35%
http/set-header.js duration=5 res='setHeader' benchmarker='wrk' *** 9.87 % ±0.83% ±1.10% ±1.44%
http/set-header.js duration=5 res='setHeaderWH' benchmarker='wrk' *** 9.59 % ±0.92% ±1.22% ±1.59%
http/simple.js duration=5 chunkedEnc=0 c=50 chunks=1 len=1024 type='buffer' benchmarker='wrk' *** 2.60 % ±0.75% ±1.00% ±1.30%
http/simple.js duration=5 chunkedEnc=0 c=50 chunks=1 len=1024 type='bytes' benchmarker='wrk' *** 9.54 % ±0.74% ±0.99% ±1.28%
http/simple.js duration=5 chunkedEnc=0 c=50 chunks=1 len=102400 type='buffer' benchmarker='wrk' ** 1.23 % ±0.75% ±0.99% ±1.29%
http/simple.js duration=5 chunkedEnc=0 c=50 chunks=1 len=102400 type='bytes' benchmarker='wrk' *** 1.98 % ±0.49% ±0.65% ±0.84%
http/simple.js duration=5 chunkedEnc=0 c=50 chunks=1 len=4 type='buffer' benchmarker='wrk' *** 2.43 % ±0.76% ±1.01% ±1.31%
http/simple.js duration=5 chunkedEnc=0 c=50 chunks=1 len=4 type='bytes' benchmarker='wrk' *** 9.55 % ±0.71% ±0.95% ±1.24%
http/simple.js duration=5 chunkedEnc=0 c=50 chunks=4 len=1024 type='buffer' benchmarker='wrk' *** 3.14 % ±0.86% ±1.15% ±1.50%
http/simple.js duration=5 chunkedEnc=0 c=50 chunks=4 len=1024 type='bytes' benchmarker='wrk' *** 2.94 % ±0.78% ±1.04% ±1.35%
http/simple.js duration=5 chunkedEnc=0 c=50 chunks=4 len=102400 type='buffer' benchmarker='wrk' *** 1.55 % ±0.62% ±0.82% ±1.07%
http/simple.js duration=5 chunkedEnc=0 c=50 chunks=4 len=102400 type='bytes' benchmarker='wrk' ** 1.10 % ±0.82% ±1.09% ±1.42%
http/simple.js duration=5 chunkedEnc=0 c=50 chunks=4 len=4 type='buffer' benchmarker='wrk' *** 3.91 % ±0.83% ±1.10% ±1.44%
http/simple.js duration=5 chunkedEnc=0 c=50 chunks=4 len=4 type='bytes' benchmarker='wrk' *** 3.47 % ±0.93% ±1.23% ±1.60%
http/simple.js duration=5 chunkedEnc=0 c=500 chunks=1 len=1024 type='buffer' benchmarker='wrk' *** 3.60 % ±0.96% ±1.27% ±1.66%
http/simple.js duration=5 chunkedEnc=0 c=500 chunks=1 len=1024 type='bytes' benchmarker='wrk' *** 9.20 % ±0.99% ±1.32% ±1.72%
http/simple.js duration=5 chunkedEnc=0 c=500 chunks=1 len=102400 type='buffer' benchmarker='wrk' *** 1.28 % ±0.53% ±0.71% ±0.93%
http/simple.js duration=5 chunkedEnc=0 c=500 chunks=1 len=102400 type='bytes' benchmarker='wrk' *** 1.28 % ±0.65% ±0.87% ±1.13%
http/simple.js duration=5 chunkedEnc=0 c=500 chunks=1 len=4 type='buffer' benchmarker='wrk' *** 3.59 % ±0.96% ±1.28% ±1.67%
http/simple.js duration=5 chunkedEnc=0 c=500 chunks=1 len=4 type='bytes' benchmarker='wrk' *** 9.93 % ±1.01% ±1.35% ±1.76%
http/simple.js duration=5 chunkedEnc=0 c=500 chunks=4 len=1024 type='buffer' benchmarker='wrk' *** 2.04 % ±0.98% ±1.31% ±1.70%
http/simple.js duration=5 chunkedEnc=0 c=500 chunks=4 len=1024 type='bytes' benchmarker='wrk' *** 2.14 % ±0.82% ±1.08% ±1.41%
http/simple.js duration=5 chunkedEnc=0 c=500 chunks=4 len=102400 type='buffer' benchmarker='wrk' *** 1.74 % ±0.67% ±0.89% ±1.16%
http/simple.js duration=5 chunkedEnc=0 c=500 chunks=4 len=102400 type='bytes' benchmarker='wrk' ** 1.10 % ±0.79% ±1.05% ±1.36%
http/simple.js duration=5 chunkedEnc=0 c=500 chunks=4 len=4 type='buffer' benchmarker='wrk' *** 3.20 % ±0.94% ±1.24% ±1.62%
http/simple.js duration=5 chunkedEnc=0 c=500 chunks=4 len=4 type='bytes' benchmarker='wrk' *** 3.12 % ±0.76% ±1.01% ±1.32%
http/simple.js duration=5 chunkedEnc=1 c=50 chunks=1 len=1024 type='buffer' benchmarker='wrk' -0.19 % ±0.80% ±1.06% ±1.38%
http/simple.js duration=5 chunkedEnc=1 c=50 chunks=1 len=1024 type='bytes' benchmarker='wrk' -0.44 % ±0.95% ±1.26% ±1.65%
http/simple.js duration=5 chunkedEnc=1 c=50 chunks=1 len=102400 type='buffer' benchmarker='wrk' 0.11 % ±0.61% ±0.81% ±1.06%
http/simple.js duration=5 chunkedEnc=1 c=50 chunks=1 len=102400 type='bytes' benchmarker='wrk' * -1.19 % ±1.11% ±1.47% ±1.92%
http/simple.js duration=5 chunkedEnc=1 c=50 chunks=1 len=4 type='buffer' benchmarker='wrk' -0.23 % ±0.80% ±1.07% ±1.39%
http/simple.js duration=5 chunkedEnc=1 c=50 chunks=1 len=4 type='bytes' benchmarker='wrk' 0.10 % ±0.75% ±1.00% ±1.30%
http/simple.js duration=5 chunkedEnc=1 c=50 chunks=4 len=1024 type='buffer' benchmarker='wrk' -0.55 % ±0.76% ±1.01% ±1.32%
http/simple.js duration=5 chunkedEnc=1 c=50 chunks=4 len=1024 type='bytes' benchmarker='wrk' 0.19 % ±0.95% ±1.27% ±1.65%
http/simple.js duration=5 chunkedEnc=1 c=50 chunks=4 len=102400 type='buffer' benchmarker='wrk' ** -1.32 % ±0.79% ±1.06% ±1.37%
http/simple.js duration=5 chunkedEnc=1 c=50 chunks=4 len=102400 type='bytes' benchmarker='wrk' 0.69 % ±1.07% ±1.42% ±1.85%
http/simple.js duration=5 chunkedEnc=1 c=50 chunks=4 len=4 type='buffer' benchmarker='wrk' 0.54 % ±0.81% ±1.07% ±1.40%
http/simple.js duration=5 chunkedEnc=1 c=50 chunks=4 len=4 type='bytes' benchmarker='wrk' 0.56 % ±0.71% ±0.95% ±1.23%
http/simple.js duration=5 chunkedEnc=1 c=500 chunks=1 len=1024 type='buffer' benchmarker='wrk' -0.48 % ±0.80% ±1.07% ±1.39%
http/simple.js duration=5 chunkedEnc=1 c=500 chunks=1 len=1024 type='bytes' benchmarker='wrk' -0.62 % ±0.85% ±1.13% ±1.48%
http/simple.js duration=5 chunkedEnc=1 c=500 chunks=1 len=102400 type='buffer' benchmarker='wrk' -0.20 % ±0.69% ±0.92% ±1.20%
http/simple.js duration=5 chunkedEnc=1 c=500 chunks=1 len=102400 type='bytes' benchmarker='wrk' 0.43 % ±1.18% ±1.56% ±2.04%
http/simple.js duration=5 chunkedEnc=1 c=500 chunks=1 len=4 type='buffer' benchmarker='wrk' 0.29 % ±0.89% ±1.19% ±1.55%
http/simple.js duration=5 chunkedEnc=1 c=500 chunks=1 len=4 type='bytes' benchmarker='wrk' * -1.01 % ±0.80% ±1.07% ±1.39%
http/simple.js duration=5 chunkedEnc=1 c=500 chunks=4 len=1024 type='buffer' benchmarker='wrk' -0.18 % ±0.68% ±0.90% ±1.18%
http/simple.js duration=5 chunkedEnc=1 c=500 chunks=4 len=1024 type='bytes' benchmarker='wrk' 0.09 % ±0.65% ±0.86% ±1.12%
http/simple.js duration=5 chunkedEnc=1 c=500 chunks=4 len=102400 type='buffer' benchmarker='wrk' * -0.55 % ±0.49% ±0.66% ±0.86%
http/simple.js duration=5 chunkedEnc=1 c=500 chunks=4 len=102400 type='bytes' benchmarker='wrk' 0.10 % ±0.82% ±1.09% ±1.42%
http/simple.js duration=5 chunkedEnc=1 c=500 chunks=4 len=4 type='buffer' benchmarker='wrk' 0.35 % ±0.74% ±0.98% ±1.28%
http/simple.js duration=5 chunkedEnc=1 c=500 chunks=4 len=4 type='bytes' benchmarker='wrk' -0.26 % ±0.65% ±0.86% ±1.12%
http/upgrade.js n=1000 0.73 % ±2.37% ±3.16% ±4.11%
http/upgrade.js n=5 6.72 % ±8.30% ±11.05% ±14.38%

Be aware that when doing many comparisons the risk of a false-positive result increases.

In this case, there are 235 comparisons, you can thus expect the following amount of false-positive results:

11.75 false positives, when considering a 5% risk acceptance (*, **, *),

2.35 false positives, when considering a 1% risk acceptance (, ),

0.24 false positives, when considering a 0.1% risk acceptance ()
Looks good I think. Headlines:
  • No notable regressions - each of the small negative cases I can see are low-confidence and fit into an overall pattern of no change considering the tests around them
  • A very consistent 9.59% - 9.87% speed up in http/set-header.js test, which tests headers + res.end(body).
  • For http/simple:

    • Consistent boost around 9.5% with type=bytes, no chunking, and len up to 1024.
    • 3% boost with type=buffer, on the same small non-chunked responses.
    • Both buffer & byte body perf dropping to about 1-2% improvement for larger bodies (1MB).
    • No significant change with chunked encoding.
  • 10.48% boost to http/end-string test with 1KB, dropping to 5.59% with 16KB, down to 2.47% improvement with 1MB.
  • ~2% boost across various http/end-vs-write-end.js cases that call end(data) on different large sizes.
Looks pretty convincing to me! All approved and ready-to-go now and I think this is all just good news, so I'll commit-queue.
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http: improve performance with known-length calls to end()
89ac179
This boosts RPS performance for the common API case where you call
`res.end(data)` with the entire response by up to 9%.
Signed-off-by: Tim Perry <pimterry@gmail.com>
PR-URL: #65466
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
Reviewed-By: Yagiz Nizipli <yagiz@nizipli.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Gürgün Dayıoğlu <hey@gurgun.day>
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http: improve performance with known-length calls to end()
c2c31d6
This boosts RPS performance for the common API case where you call
`res.end(data)` with the entire response by up to 9%.
Signed-off-by: Tim Perry <pimterry@gmail.com>
PR-URL: #65466
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
Reviewed-By: Yagiz Nizipli <yagiz@nizipli.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Gürgün Dayıoğlu <hey@gurgun.day>
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http: improve performance with known-length calls to end()
5b13d30
This boosts RPS performance for the common API case where you call
`res.end(data)` with the entire response by up to 9%.
Signed-off-by: Tim Perry <pimterry@gmail.com>
PR-URL: #65466
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
Reviewed-By: Yagiz Nizipli <yagiz@nizipli.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Gürgün Dayıoğlu <hey@gurgun.day>
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injectUserscript("// Force GitHub README to respect dark mode\n(function() {\n var style = document.createElement('style');\n style.textContent = '\n .markdown-body {\n color-scheme: dark light;\n }\n .markdown-body pre { background: #161b22 !important; }\n .markdown-body code { background: rgba(110, 118, 129, 0.4) !important; }\n .markdown-body table th, .markdown-body table td { border-color: #30363d !important; }\n .markdown-body img { background: #0d1117; }\n .markdown-body blockquote { border-left-color: #8b949e; }\n .markdown-body hr { border-color: #30363d; }\n ';\n document.head.appendChild(style);\n})();", "GitHub Dark Mode README Fix");
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http: improve performance for end() with known-length string - #65466
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When you call end(data) on an outgoing HTTP request, we previously wrote the data, and then ran _send('', ...) just to trigger flushing the headers, which resulted in an extra zero-byte write call and bonus nextTick before 'finish'.
When the length is known and content-length is used (not chunking, so we don't need a terminator) we can skip this completely: prep the content-length header explicitly, and combine the finish into the existing write step.
This drops a nextTick, and goes from 2 write calls to 1 for the very common case of response.end(data) with a string, and for buffer data goes from 3 writes to 2.
In practice, in the tiny benchmark here which I think represents a very common use case (small API responses) I see this boosting HTTP RPS by up to 9% for writes up to 1KB or so. For larger responses the response write time starts to outweigh this, but I still see 3% RPS boost at 16KB. Needs autocannon to hit the rates required, you can test yourself with:
node benchmark/compare.js --old ./node-main --new ./node-pr --runs 20 --set benchmarker=autocannon --filter end-string http
Added a new test confirming the specific details and edge cases this touches, and updated one existing test which specifically asserted that end(data) triggered two writes, including the empty one.
@pimterry
http: improve performance with known-length calls to end()
659d6b9
This boosts RPS performance for the common API case where you call
`res.end(data)` with the entire response by up to 9%.
Signed-off-by: Tim Perry <pimterry@gmail.com>
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Codecov Report
✅ All modified and coverable lines are covered by tests.

✅ Project coverage is 90.13%. Comparing base (15940ef) to head (659d6b9).
⚠️ Report is 61 commits behind head on main.
Additional details and impacted files
@@ Coverage Diff @@## main #65466 +/- ##
==========================================
- Coverage 90.14% 90.13% -0.01% 
==========================================
Files 751 751 Lines 252298 252333 +35 Branches 47446 47449 +3 ==========================================
+ Hits 227436 227451 +15 - Misses 16175 16186 +11 - Partials 8687 8696 +9 
Files with missing linesCoverage Δ
lib/_http_outgoing.js97.76% <100.00%> (-0.02%)⬇️
... and 34 files with indirect coverage changes
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  • ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.
  • 📦 JS Bundle Analysis: Save yourself from yourself by tracking and limiting bundle sizes in JS merges.
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CI: https://ci.nodejs.org/job/node-test-pull-request/76211/
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@bjohansebas benchmark label was a good suggestion. I've done a run here.
Unfortunately it seems like the microbenchmark job is broken generally (cc @nodejs/build) and all recent jobs have failed with:
++ Rscript benchmark/compare.R
Error: package or namespace load failed for ‘ggplot2’ in dyn.load(file, DLLpath = DLLpath, ...):
unable to load shared object '/usr/local/lib/R/site-library/rlang/libs/rlang.so':
/usr/local/lib/R/site-library/rlang/libs/rlang.so: undefined symbol: SETLENGTH
Execution halted

I've manually extracted the CSV from the console output to get some numbers though, and run node-benchmark-compare on the result, which gives:
Details
 confidence improvement accuracy (*) (**) (***)
http/bench-parser-fragmented.js n=100000 frags=2 len=16 -0.20 % ±1.06% ±1.42% ±1.85%
http/bench-parser-fragmented.js n=100000 frags=2 len=8 -0.01 % ±0.94% ±1.25% ±1.63%
http/bench-parser-fragmented.js n=100000 frags=4 len=16 -0.17 % ±0.77% ±1.02% ±1.33%
http/bench-parser-fragmented.js n=100000 frags=4 len=8 -0.57 % ±0.64% ±0.85% ±1.11%
http/bench-parser-fragmented.js n=100000 frags=8 len=16 -0.07 % ±0.84% ±1.12% ±1.45%
http/bench-parser-fragmented.js n=100000 frags=8 len=8 0.43 % ±0.78% ±1.04% ±1.35%
http/bench-parser.js n=100000 len=16 0.20 % ±0.93% ±1.24% ±1.61%
http/bench-parser.js n=100000 len=32 0.03 % ±0.68% ±0.90% ±1.17%
http/bench-parser.js n=100000 len=4 0.60 % ±1.08% ±1.43% ±1.86%
http/bench-parser.js n=100000 len=8 0.32 % ±1.11% ±1.47% ±1.92%
http/check_invalid_header_char.js n=1000000 input='' 1.25 % ±2.48% ±3.30% ±4.30%
http/check_invalid_header_char.js n=1000000 input='\t\t\t\t\t\t\t\t\t\tFoo bar baz' 0.39 % ±1.66% ±2.21% ±2.88%
http/check_invalid_header_char.js n=1000000 input='\x7F' * 4.92 % ±3.90% ±5.19% ±6.75%
http/check_invalid_header_char.js n=1000000 input='1' -0.41 % ±3.47% ±4.62% ±6.02%
http/check_invalid_header_char.js n=1000000 input='20091' -0.50 % ±3.85% ±5.12% ±6.66%
http/check_invalid_header_char.js n=1000000 input='close' 0.49 % ±3.34% ±4.44% ±5.78%
http/check_invalid_header_char.js n=1000000 input='en-US' -0.66 % ±3.59% ±4.77% ±6.21%
http/check_invalid_header_char.js n=1000000 input='foo\nbar' -1.88 % ±2.70% ±3.60% ±4.70%
http/check_invalid_header_char.js n=1000000 input='group_acmeair' 0.85 % ±1.82% ±2.42% ±3.16%
http/check_invalid_header_char.js n=1000000 input='gzip' -0.60 % ±3.29% ±4.37% ±5.70%
http/check_invalid_header_char.js n=1000000 input='keep-alive' -1.28 % ±2.16% ±2.88% ±3.75%
http/check_invalid_header_char.js n=1000000 input='LONG_AND_INVALID' 0.08 % ±1.13% ±1.51% ±1.97%
http/check_invalid_header_char.js n=1000000 input='private' 1.00 % ±2.68% ±3.57% ±4.65%
http/check_invalid_header_char.js n=1000000 input='SAMEORIGIN' 1.36 % ±2.81% ±3.74% ±4.88%
http/check_invalid_header_char.js n=1000000 input='Sat, 07 May 2016 16:54:48 GMT' 0.79 % ±1.41% ±1.87% ±2.44%
http/check_invalid_header_char.js n=1000000 input='text/html; charset=utf-8' -0.12 % ±1.41% ±1.88% ±2.45%
http/check_invalid_header_char.js n=1000000 input='text/plain' -1.49 % ±2.96% ±3.95% ±5.14%
http/check_invalid_header_char.js n=1000000 input='中文呢' 1.95 % ±2.71% ±3.61% ±4.69%
http/check_is_http_token.js n=1000000 key=':' -0.22 % ±2.22% ±2.96% ±3.85%
http/check_is_http_token.js n=1000000 key=':alternate-protocol' 2.82 % ±4.07% ±5.42% ±7.06%
http/check_is_http_token.js n=1000000 key='((((())))' -1.22 % ±2.75% ±3.71% ±4.91%
http/check_is_http_token.js n=1000000 key='@@' 0.52 % ±2.14% ±2.85% ±3.71%
http/check_is_http_token.js n=1000000 key='Accept-Ranges' 0.51 % ±2.25% ±2.99% ±3.90%
http/check_is_http_token.js n=1000000 key='alt-svc' -0.09 % ±2.23% ±2.97% ±3.87%
http/check_is_http_token.js n=1000000 key='alternate-protocol:' -0.94 % ±2.08% ±2.77% ±3.61%
http/check_is_http_token.js n=1000000 key='alternate-protocol' -1.19 % ±2.32% ±3.09% ±4.03%
http/check_is_http_token.js n=1000000 key='Cache-Control' -0.96 % ±2.14% ±2.85% ±3.71%
http/check_is_http_token.js n=1000000 key='Connection' 0.78 % ±2.39% ±3.19% ±4.15%
http/check_is_http_token.js n=1000000 key='Content-Encoding' * -2.76 % ±2.26% ±3.01% ±3.92%
http/check_is_http_token.js n=1000000 key='content-length' 0.93 % ±2.27% ±3.02% ±3.92%
http/check_is_http_token.js n=1000000 key='Content-Location' -0.15 % ±2.52% ±3.35% ±4.36%
http/check_is_http_token.js n=1000000 key='content-type' -0.49 % ±2.55% ±3.39% ±4.41%
http/check_is_http_token.js n=1000000 key='Content-Type' 0.46 % ±2.58% ±3.43% ±4.47%
http/check_is_http_token.js n=1000000 key='date' 0.62 % ±2.42% ±3.22% ±4.19%
http/check_is_http_token.js n=1000000 key='ETag' -2.60 % ±3.97% ±5.32% ±7.01%
http/check_is_http_token.js n=1000000 key='Expires' ** 3.69 % ±2.64% ±3.52% ±4.59%
http/check_is_http_token.js n=1000000 key='Keep-Alive' -0.03 % ±2.59% ±3.45% ±4.48%
http/check_is_http_token.js n=1000000 key='Last-Modified' -0.99 % ±2.34% ±3.12% ±4.07%
http/check_is_http_token.js n=1000000 key='location' 0.79 % ±2.44% ±3.25% ±4.23%
http/check_is_http_token.js n=1000000 key='server' 0.37 % ±2.46% ±3.27% ±4.25%
http/check_is_http_token.js n=1000000 key='Server' * 3.70 % ±3.00% ±4.00% ±5.23%
http/check_is_http_token.js n=1000000 key='status' ** -4.32 % ±3.09% ±4.13% ±5.40%
http/check_is_http_token.js n=1000000 key='TCN' -0.86 % ±1.00% ±1.33% ±1.73%
http/check_is_http_token.js n=1000000 key='Transfer-Encoding' -1.00 % ±2.32% ±3.09% ±4.02%
http/check_is_http_token.js n=1000000 key='Vary' -0.56 % ±1.47% ±1.95% ±2.54%
http/check_is_http_token.js n=1000000 key='version' 1.90 % ±2.74% ±3.65% ±4.75%
http/check_is_http_token.js n=1000000 key='x-frame-options' 0.57 % ±2.05% ±2.73% ±3.55%
http/check_is_http_token.js n=1000000 key='x-xss-protection' -1.39 % ±2.29% ±3.06% ±3.99%
http/check_is_http_token.js n=1000000 key='中文呢' -1.00 % ±4.47% ±6.01% ±7.92%
http/chunked.js duration=5 c=100 len=1 n=1 benchmarker='wrk' -0.19 % ±0.68% ±0.91% ±1.18%
http/chunked.js duration=5 c=100 len=1 n=16 benchmarker='wrk' 0.41 % ±0.78% ±1.03% ±1.35%
http/chunked.js duration=5 c=100 len=1 n=4 benchmarker='wrk' 0.61 % ±2.08% ±2.76% ±3.60%
http/chunked.js duration=5 c=100 len=1 n=8 benchmarker='wrk' 0.13 % ±0.81% ±1.07% ±1.40%
http/chunked.js duration=5 c=100 len=256 n=1 benchmarker='wrk' -0.10 % ±0.70% ±0.93% ±1.21%
http/chunked.js duration=5 c=100 len=256 n=16 benchmarker='wrk' -0.70 % ±0.73% ±0.97% ±1.26%
http/chunked.js duration=5 c=100 len=256 n=4 benchmarker='wrk' -0.58 % ±1.84% ±2.45% ±3.18%
http/chunked.js duration=5 c=100 len=256 n=8 benchmarker='wrk' 0.11 % ±0.87% ±1.16% ±1.51%
http/chunked.js duration=5 c=100 len=64 n=1 benchmarker='wrk' -0.26 % ±0.60% ±0.80% ±1.04%
http/chunked.js duration=5 c=100 len=64 n=16 benchmarker='wrk' 0.56 % ±0.63% ±0.84% ±1.10%
http/chunked.js duration=5 c=100 len=64 n=4 benchmarker='wrk' 0.08 % ±1.81% ±2.41% ±3.15%
http/chunked.js duration=5 c=100 len=64 n=8 benchmarker='wrk' 0.26 % ±0.75% ±1.00% ±1.30%
http/client-request-body.js method='end' len=1024 type='asc' dur=5 -0.06 % ±0.69% ±0.92% ±1.20%
http/client-request-body.js method='end' len=1024 type='buf' dur=5 0.01 % ±0.76% ±1.02% ±1.32%
http/client-request-body.js method='end' len=1024 type='utf' dur=5 -0.28 % ±0.59% ±0.79% ±1.03%
http/client-request-body.js method='end' len=256 type='asc' dur=5 -0.49 % ±0.67% ±0.90% ±1.17%
http/client-request-body.js method='end' len=256 type='buf' dur=5 * -0.75 % ±0.68% ±0.90% ±1.18%
http/client-request-body.js method='end' len=256 type='utf' dur=5 0.03 % ±0.62% ±0.83% ±1.08%
http/client-request-body.js method='end' len=32 type='asc' dur=5 -0.01 % ±0.56% ±0.75% ±0.98%
http/client-request-body.js method='end' len=32 type='buf' dur=5 -0.37 % ±0.60% ±0.79% ±1.03%
http/client-request-body.js method='end' len=32 type='utf' dur=5 -0.16 % ±0.62% ±0.83% ±1.08%
http/client-request-body.js method='write' len=1024 type='asc' dur=5 -0.16 % ±0.78% ±1.03% ±1.34%
http/client-request-body.js method='write' len=1024 type='buf' dur=5 -0.34 % ±0.68% ±0.90% ±1.17%
http/client-request-body.js method='write' len=1024 type='utf' dur=5 0.06 % ±0.78% ±1.04% ±1.35%
http/client-request-body.js method='write' len=256 type='asc' dur=5 0.27 % ±0.70% ±0.93% ±1.21%
http/client-request-body.js method='write' len=256 type='buf' dur=5 0.09 % ±0.76% ±1.02% ±1.32%
http/client-request-body.js method='write' len=256 type='utf' dur=5 0.49 % ±0.59% ±0.79% ±1.03%
http/client-request-body.js method='write' len=32 type='asc' dur=5 -0.40 % ±0.64% ±0.86% ±1.11%
http/client-request-body.js method='write' len=32 type='buf' dur=5 -0.21 % ±0.65% ±0.86% ±1.12%
http/client-request-body.js method='write' len=32 type='utf' dur=5 0.02 % ±0.60% ±0.79% ±1.03%
http/cluster.js duration=5 c=50 len=1024 type='buffer' benchmarker='wrk' 0.13 % ±0.46% ±0.62% ±0.81%
http/cluster.js duration=5 c=50 len=1024 type='bytes' benchmarker='wrk' -0.11 % ±0.38% ±0.50% ±0.66%
http/cluster.js duration=5 c=50 len=102400 type='buffer' benchmarker='wrk' -0.24 % ±0.49% ±0.65% ±0.85%
http/cluster.js duration=5 c=50 len=102400 type='bytes' benchmarker='wrk' 0.14 % ±0.80% ±1.06% ±1.38%
http/cluster.js duration=5 c=50 len=4 type='buffer' benchmarker='wrk' -0.23 % ±0.29% ±0.39% ±0.51%
http/cluster.js duration=5 c=50 len=4 type='bytes' benchmarker='wrk' 0.00 % ±0.51% ±0.67% ±0.88%
http/cluster.js duration=5 c=500 len=1024 type='buffer' benchmarker='wrk' ** -0.77 % ±0.50% ±0.67% ±0.87%
http/cluster.js duration=5 c=500 len=1024 type='bytes' benchmarker='wrk' -0.18 % ±0.65% ±0.86% ±1.12%
http/cluster.js duration=5 c=500 len=102400 type='buffer' benchmarker='wrk' -0.18 % ±0.59% ±0.78% ±1.02%
http/cluster.js duration=5 c=500 len=102400 type='bytes' benchmarker='wrk' 0.28 % ±0.72% ±0.95% ±1.24%
http/cluster.js duration=5 c=500 len=4 type='buffer' benchmarker='wrk' -0.25 % ±0.47% ±0.62% ±0.81%
http/cluster.js duration=5 c=500 len=4 type='bytes' benchmarker='wrk' -0.36 % ±0.52% ±0.70% ±0.91%
http/create-clientrequest.js e=1 arg='options' url='idn' 2.09 % ±7.80% ±10.38% ±13.50%
http/create-clientrequest.js e=1 arg='options' url='long' -9.98 % ±14.10% ±18.77% ±24.46%
http/create-clientrequest.js e=1 arg='options' url='wpt' -4.69 % ±6.75% ±8.98% ±11.70%
http/create-clientrequest.js e=1 arg='string' url='idn' -4.15 % ±10.23% ±13.61% ±17.71%
http/create-clientrequest.js e=1 arg='string' url='long' -0.93 % ±12.77% ±16.99% ±22.12%
http/create-clientrequest.js e=1 arg='string' url='wpt' 0.60 % ±11.36% ±15.12% ±19.68%
http/create-clientrequest.js e=1 arg='URL' url='idn' 0.87 % ±9.17% ±12.20% ±15.88%
http/create-clientrequest.js e=1 arg='URL' url='long' -5.01 % ±10.02% ±13.35% ±17.41%
http/create-clientrequest.js e=1 arg='URL' url='wpt' 1.99 % ±8.00% ±10.64% ±13.85%
http/end-string.js duration=5 c=50 len=1024 benchmarker='wrk' *** 10.48 % ±0.81% ±1.08% ±1.41%
http/end-string.js duration=5 c=50 len=102400 benchmarker='wrk' *** 2.47 % ±0.50% ±0.66% ±0.86%
http/end-string.js duration=5 c=50 len=16384 benchmarker='wrk' *** 5.59 % ±0.89% ±1.19% ±1.55%
http/end-string.js duration=5 c=50 len=4 benchmarker='wrk' *** 9.92 % ±0.82% ±1.10% ±1.43%
http/end-string.js duration=5 c=50 len=64 benchmarker='wrk' *** 8.43 % ±0.71% ±0.94% ±1.23%
http/end-vs-write-end.js duration=5 method='end' c=100 len=1048576 type='asc' benchmarker='wrk' *** 2.48 % ±0.47% ±0.62% ±0.81%
http/end-vs-write-end.js duration=5 method='end' c=100 len=1048576 type='buf' benchmarker='wrk' -0.12 % ±0.43% ±0.57% ±0.74%
http/end-vs-write-end.js duration=5 method='end' c=100 len=1048576 type='utf' benchmarker='wrk' *** 0.68 % ±0.38% ±0.51% ±0.66%
http/end-vs-write-end.js duration=5 method='end' c=100 len=131072 type='asc' benchmarker='wrk' ** 1.19 % ±0.81% ±1.09% ±1.43%
http/end-vs-write-end.js duration=5 method='end' c=100 len=131072 type='buf' benchmarker='wrk' *** 1.50 % ±0.59% ±0.78% ±1.01%
http/end-vs-write-end.js duration=5 method='end' c=100 len=131072 type='utf' benchmarker='wrk' *** 2.25 % ±0.45% ±0.59% ±0.77%
http/end-vs-write-end.js duration=5 method='end' c=100 len=262144 type='asc' benchmarker='wrk' *** 1.18 % ±0.42% ±0.56% ±0.73%
http/end-vs-write-end.js duration=5 method='end' c=100 len=262144 type='buf' benchmarker='wrk' *** 0.92 % ±0.48% ±0.63% ±0.83%
http/end-vs-write-end.js duration=5 method='end' c=100 len=262144 type='utf' benchmarker='wrk' *** 1.25 % ±0.32% ±0.43% ±0.56%
http/end-vs-write-end.js duration=5 method='end' c=100 len=65536 type='asc' benchmarker='wrk' *** 1.60 % ±0.83% ±1.10% ±1.44%
http/end-vs-write-end.js duration=5 method='end' c=100 len=65536 type='buf' benchmarker='wrk' *** 2.34 % ±0.88% ±1.18% ±1.53%
http/end-vs-write-end.js duration=5 method='end' c=100 len=65536 type='utf' benchmarker='wrk' *** 2.95 % ±0.48% ±0.64% ±0.83%
http/end-vs-write-end.js duration=5 method='write' c=100 len=1048576 type='asc' benchmarker='wrk' -0.33 % ±0.57% ±0.77% ±1.00%
http/end-vs-write-end.js duration=5 method='write' c=100 len=1048576 type='buf' benchmarker='wrk' -0.16 % ±0.52% ±0.69% ±0.90%
http/end-vs-write-end.js duration=5 method='write' c=100 len=1048576 type='utf' benchmarker='wrk' -0.12 % ±0.36% ±0.47% ±0.62%
http/end-vs-write-end.js duration=5 method='write' c=100 len=131072 type='asc' benchmarker='wrk' 0.07 % ±0.76% ±1.01% ±1.32%
http/end-vs-write-end.js duration=5 method='write' c=100 len=131072 type='buf' benchmarker='wrk' -0.25 % ±0.51% ±0.68% ±0.89%
http/end-vs-write-end.js duration=5 method='write' c=100 len=131072 type='utf' benchmarker='wrk' 0.53 % ±1.00% ±1.34% ±1.74%
http/end-vs-write-end.js duration=5 method='write' c=100 len=262144 type='asc' benchmarker='wrk' -0.26 % ±0.61% ±0.81% ±1.06%
http/end-vs-write-end.js duration=5 method='write' c=100 len=262144 type='buf' benchmarker='wrk' -0.05 % ±0.47% ±0.62% ±0.81%
http/end-vs-write-end.js duration=5 method='write' c=100 len=262144 type='utf' benchmarker='wrk' -0.08 % ±0.56% ±0.74% ±0.96%
http/end-vs-write-end.js duration=5 method='write' c=100 len=65536 type='asc' benchmarker='wrk' -0.50 % ±0.96% ±1.28% ±1.66%
http/end-vs-write-end.js duration=5 method='write' c=100 len=65536 type='buf' benchmarker='wrk' -0.22 % ±0.71% ±0.94% ±1.23%
http/end-vs-write-end.js duration=5 method='write' c=100 len=65536 type='utf' benchmarker='wrk' 0.10 % ±0.58% ±0.77% ±1.01%
http/headers.js group='fewHeaders' duration=5 len=1 n=10 benchmarker='wrk' -0.23 % ±0.65% ±0.86% ±1.13%
http/headers.js group='fewHeaders' duration=5 len=5 n=10 benchmarker='wrk' 0.25 % ±0.59% ±0.79% ±1.03%
http/headers.js group='manyHeaders' duration=5 len=1 n=600 benchmarker='wrk' -0.11 % ±0.86% ±1.15% ±1.49%
http/headers.js group='manyHeaders' duration=5 len=100 n=600 benchmarker='wrk' 0.22 % ±1.12% ±1.49% ±1.94%
http/headers.js group='mediumHeaders' duration=5 len=1 n=50 benchmarker='wrk' -0.28 % ±0.51% ±0.67% ±0.88%
http/headers.js group='mediumHeaders' duration=5 len=10 n=50 benchmarker='wrk' 0.04 % ±0.53% ±0.71% ±0.93%
http/http_server_for_chunky_client.js type='send' n=2000 len=1 0.19 % ±0.57% ±0.77% ±1.00%
http/http_server_for_chunky_client.js type='send' n=2000 len=128 -0.12 % ±0.59% ±0.78% ±1.02%
http/http_server_for_chunky_client.js type='send' n=2000 len=16 -0.01 % ±0.60% ±0.79% ±1.03%
http/http_server_for_chunky_client.js type='send' n=2000 len=32 0.15 % ±0.61% ±0.81% ±1.06%
http/http_server_for_chunky_client.js type='send' n=2000 len=4 0.67 % ±0.69% ±0.92% ±1.21%
http/http_server_for_chunky_client.js type='send' n=2000 len=64 -0.30 % ±0.48% ±0.64% ±0.83%
http/http_server_for_chunky_client.js type='send' n=2000 len=8 -0.50 % ±0.55% ±0.73% ±0.95%
http/http_server_for_chunky_client.js type='send' n=5 len=1 -1.39 % ±2.60% ±3.47% ±4.51%
http/http_server_for_chunky_client.js type='send' n=5 len=128 -4.15 % ±13.02% ±17.32% ±22.54%
http/http_server_for_chunky_client.js type='send' n=5 len=16 7.54 % ±10.05% ±13.50% ±17.81%
http/http_server_for_chunky_client.js type='send' n=5 len=32 0.87 % ±11.95% ±15.91% ±20.71%
http/http_server_for_chunky_client.js type='send' n=5 len=4 1.73 % ±10.57% ±14.06% ±18.30%
http/http_server_for_chunky_client.js type='send' n=5 len=64 -5.12 % ±14.17% ±18.86% ±24.56%
http/http_server_for_chunky_client.js type='send' n=5 len=8 -2.55 % ±5.92% ±7.90% ±10.32%
http/http_server_for_chunky_client.js type='send' n=50 len=1 1.27 % ±2.86% ±3.81% ±4.96%
http/http_server_for_chunky_client.js type='send' n=50 len=128 * 5.17 % ±4.13% ±5.49% ±7.15%
http/http_server_for_chunky_client.js type='send' n=50 len=16 -0.71 % ±2.69% ±3.58% ±4.67%
http/http_server_for_chunky_client.js type='send' n=50 len=32 -0.12 % ±2.72% ±3.63% ±4.74%
http/http_server_for_chunky_client.js type='send' n=50 len=4 -1.47 % ±3.06% ±4.07% ±5.29%
http/http_server_for_chunky_client.js type='send' n=50 len=64 2.04 % ±3.51% ±4.67% ±6.09%
http/http_server_for_chunky_client.js type='send' n=50 len=8 -0.08 % ±2.21% ±2.94% ±3.84%
http/http_server_for_chunky_client.js type='send' n=500 len=1 -0.08 % ±0.80% ±1.07% ±1.40%
http/http_server_for_chunky_client.js type='send' n=500 len=128 -0.38 % ±0.70% ±0.93% ±1.21%
http/http_server_for_chunky_client.js type='send' n=500 len=16 * -0.94 % ±0.83% ±1.11% ±1.45%
http/http_server_for_chunky_client.js type='send' n=500 len=32 -0.43 % ±0.83% ±1.11% ±1.45%
http/http_server_for_chunky_client.js type='send' n=500 len=4 -0.02 % ±0.71% ±0.95% ±1.24%
http/http_server_for_chunky_client.js type='send' n=500 len=64 -0.19 % ±0.93% ±1.24% ±1.62%
http/http_server_for_chunky_client.js type='send' n=500 len=8 -0.15 % ±0.71% ±0.95% ±1.23%
http/incoming_headers.js duration=5 w=0 headers=20 connections=50 benchmarker='wrk' 0.04 % ±0.81% ±1.08% ±1.42%
http/incoming_headers.js duration=5 w=6 headers=20 connections=50 benchmarker='wrk' 0.04 % ±0.64% ±0.85% ±1.11%
http/set_header.js n=1000000 value='Connection' ** -2.20 % ±1.65% ±2.19% ±2.85%
http/set_header.js n=1000000 value='Content-Length' 0.29 % ±1.71% ±2.28% ±2.97%
http/set_header.js n=1000000 value='Content-Type' 1.33 % ±1.88% ±2.51% ±3.27%
http/set_header.js n=1000000 value='Set-Cookie' 1.14 % ±1.33% ±1.77% ±2.30%
http/set_header.js n=1000000 value='Transfer-Encoding' 1.06 % ±1.33% ±1.76% ±2.30%
http/set_header.js n=1000000 value='Vary' -0.57 % ±1.72% ±2.29% ±2.99%
http/set_header.js n=1000000 value='X-Powered-By' * 1.49 % ±1.33% ±1.77% ±2.30%
http/set-header.js duration=5 res='normal' benchmarker='wrk' *** 9.74 % ±0.78% ±1.04% ±1.35%
http/set-header.js duration=5 res='setHeader' benchmarker='wrk' *** 9.87 % ±0.83% ±1.10% ±1.44%
http/set-header.js duration=5 res='setHeaderWH' benchmarker='wrk' *** 9.59 % ±0.92% ±1.22% ±1.59%
http/simple.js duration=5 chunkedEnc=0 c=50 chunks=1 len=1024 type='buffer' benchmarker='wrk' *** 2.60 % ±0.75% ±1.00% ±1.30%
http/simple.js duration=5 chunkedEnc=0 c=50 chunks=1 len=1024 type='bytes' benchmarker='wrk' *** 9.54 % ±0.74% ±0.99% ±1.28%
http/simple.js duration=5 chunkedEnc=0 c=50 chunks=1 len=102400 type='buffer' benchmarker='wrk' ** 1.23 % ±0.75% ±0.99% ±1.29%
http/simple.js duration=5 chunkedEnc=0 c=50 chunks=1 len=102400 type='bytes' benchmarker='wrk' *** 1.98 % ±0.49% ±0.65% ±0.84%
http/simple.js duration=5 chunkedEnc=0 c=50 chunks=1 len=4 type='buffer' benchmarker='wrk' *** 2.43 % ±0.76% ±1.01% ±1.31%
http/simple.js duration=5 chunkedEnc=0 c=50 chunks=1 len=4 type='bytes' benchmarker='wrk' *** 9.55 % ±0.71% ±0.95% ±1.24%
http/simple.js duration=5 chunkedEnc=0 c=50 chunks=4 len=1024 type='buffer' benchmarker='wrk' *** 3.14 % ±0.86% ±1.15% ±1.50%
http/simple.js duration=5 chunkedEnc=0 c=50 chunks=4 len=1024 type='bytes' benchmarker='wrk' *** 2.94 % ±0.78% ±1.04% ±1.35%
http/simple.js duration=5 chunkedEnc=0 c=50 chunks=4 len=102400 type='buffer' benchmarker='wrk' *** 1.55 % ±0.62% ±0.82% ±1.07%
http/simple.js duration=5 chunkedEnc=0 c=50 chunks=4 len=102400 type='bytes' benchmarker='wrk' ** 1.10 % ±0.82% ±1.09% ±1.42%
http/simple.js duration=5 chunkedEnc=0 c=50 chunks=4 len=4 type='buffer' benchmarker='wrk' *** 3.91 % ±0.83% ±1.10% ±1.44%
http/simple.js duration=5 chunkedEnc=0 c=50 chunks=4 len=4 type='bytes' benchmarker='wrk' *** 3.47 % ±0.93% ±1.23% ±1.60%
http/simple.js duration=5 chunkedEnc=0 c=500 chunks=1 len=1024 type='buffer' benchmarker='wrk' *** 3.60 % ±0.96% ±1.27% ±1.66%
http/simple.js duration=5 chunkedEnc=0 c=500 chunks=1 len=1024 type='bytes' benchmarker='wrk' *** 9.20 % ±0.99% ±1.32% ±1.72%
http/simple.js duration=5 chunkedEnc=0 c=500 chunks=1 len=102400 type='buffer' benchmarker='wrk' *** 1.28 % ±0.53% ±0.71% ±0.93%
http/simple.js duration=5 chunkedEnc=0 c=500 chunks=1 len=102400 type='bytes' benchmarker='wrk' *** 1.28 % ±0.65% ±0.87% ±1.13%
http/simple.js duration=5 chunkedEnc=0 c=500 chunks=1 len=4 type='buffer' benchmarker='wrk' *** 3.59 % ±0.96% ±1.28% ±1.67%
http/simple.js duration=5 chunkedEnc=0 c=500 chunks=1 len=4 type='bytes' benchmarker='wrk' *** 9.93 % ±1.01% ±1.35% ±1.76%
http/simple.js duration=5 chunkedEnc=0 c=500 chunks=4 len=1024 type='buffer' benchmarker='wrk' *** 2.04 % ±0.98% ±1.31% ±1.70%
http/simple.js duration=5 chunkedEnc=0 c=500 chunks=4 len=1024 type='bytes' benchmarker='wrk' *** 2.14 % ±0.82% ±1.08% ±1.41%
http/simple.js duration=5 chunkedEnc=0 c=500 chunks=4 len=102400 type='buffer' benchmarker='wrk' *** 1.74 % ±0.67% ±0.89% ±1.16%
http/simple.js duration=5 chunkedEnc=0 c=500 chunks=4 len=102400 type='bytes' benchmarker='wrk' ** 1.10 % ±0.79% ±1.05% ±1.36%
http/simple.js duration=5 chunkedEnc=0 c=500 chunks=4 len=4 type='buffer' benchmarker='wrk' *** 3.20 % ±0.94% ±1.24% ±1.62%
http/simple.js duration=5 chunkedEnc=0 c=500 chunks=4 len=4 type='bytes' benchmarker='wrk' *** 3.12 % ±0.76% ±1.01% ±1.32%
http/simple.js duration=5 chunkedEnc=1 c=50 chunks=1 len=1024 type='buffer' benchmarker='wrk' -0.19 % ±0.80% ±1.06% ±1.38%
http/simple.js duration=5 chunkedEnc=1 c=50 chunks=1 len=1024 type='bytes' benchmarker='wrk' -0.44 % ±0.95% ±1.26% ±1.65%
http/simple.js duration=5 chunkedEnc=1 c=50 chunks=1 len=102400 type='buffer' benchmarker='wrk' 0.11 % ±0.61% ±0.81% ±1.06%
http/simple.js duration=5 chunkedEnc=1 c=50 chunks=1 len=102400 type='bytes' benchmarker='wrk' * -1.19 % ±1.11% ±1.47% ±1.92%
http/simple.js duration=5 chunkedEnc=1 c=50 chunks=1 len=4 type='buffer' benchmarker='wrk' -0.23 % ±0.80% ±1.07% ±1.39%
http/simple.js duration=5 chunkedEnc=1 c=50 chunks=1 len=4 type='bytes' benchmarker='wrk' 0.10 % ±0.75% ±1.00% ±1.30%
http/simple.js duration=5 chunkedEnc=1 c=50 chunks=4 len=1024 type='buffer' benchmarker='wrk' -0.55 % ±0.76% ±1.01% ±1.32%
http/simple.js duration=5 chunkedEnc=1 c=50 chunks=4 len=1024 type='bytes' benchmarker='wrk' 0.19 % ±0.95% ±1.27% ±1.65%
http/simple.js duration=5 chunkedEnc=1 c=50 chunks=4 len=102400 type='buffer' benchmarker='wrk' ** -1.32 % ±0.79% ±1.06% ±1.37%
http/simple.js duration=5 chunkedEnc=1 c=50 chunks=4 len=102400 type='bytes' benchmarker='wrk' 0.69 % ±1.07% ±1.42% ±1.85%
http/simple.js duration=5 chunkedEnc=1 c=50 chunks=4 len=4 type='buffer' benchmarker='wrk' 0.54 % ±0.81% ±1.07% ±1.40%
http/simple.js duration=5 chunkedEnc=1 c=50 chunks=4 len=4 type='bytes' benchmarker='wrk' 0.56 % ±0.71% ±0.95% ±1.23%
http/simple.js duration=5 chunkedEnc=1 c=500 chunks=1 len=1024 type='buffer' benchmarker='wrk' -0.48 % ±0.80% ±1.07% ±1.39%
http/simple.js duration=5 chunkedEnc=1 c=500 chunks=1 len=1024 type='bytes' benchmarker='wrk' -0.62 % ±0.85% ±1.13% ±1.48%
http/simple.js duration=5 chunkedEnc=1 c=500 chunks=1 len=102400 type='buffer' benchmarker='wrk' -0.20 % ±0.69% ±0.92% ±1.20%
http/simple.js duration=5 chunkedEnc=1 c=500 chunks=1 len=102400 type='bytes' benchmarker='wrk' 0.43 % ±1.18% ±1.56% ±2.04%
http/simple.js duration=5 chunkedEnc=1 c=500 chunks=1 len=4 type='buffer' benchmarker='wrk' 0.29 % ±0.89% ±1.19% ±1.55%
http/simple.js duration=5 chunkedEnc=1 c=500 chunks=1 len=4 type='bytes' benchmarker='wrk' * -1.01 % ±0.80% ±1.07% ±1.39%
http/simple.js duration=5 chunkedEnc=1 c=500 chunks=4 len=1024 type='buffer' benchmarker='wrk' -0.18 % ±0.68% ±0.90% ±1.18%
http/simple.js duration=5 chunkedEnc=1 c=500 chunks=4 len=1024 type='bytes' benchmarker='wrk' 0.09 % ±0.65% ±0.86% ±1.12%
http/simple.js duration=5 chunkedEnc=1 c=500 chunks=4 len=102400 type='buffer' benchmarker='wrk' * -0.55 % ±0.49% ±0.66% ±0.86%
http/simple.js duration=5 chunkedEnc=1 c=500 chunks=4 len=102400 type='bytes' benchmarker='wrk' 0.10 % ±0.82% ±1.09% ±1.42%
http/simple.js duration=5 chunkedEnc=1 c=500 chunks=4 len=4 type='buffer' benchmarker='wrk' 0.35 % ±0.74% ±0.98% ±1.28%
http/simple.js duration=5 chunkedEnc=1 c=500 chunks=4 len=4 type='bytes' benchmarker='wrk' -0.26 % ±0.65% ±0.86% ±1.12%
http/upgrade.js n=1000 0.73 % ±2.37% ±3.16% ±4.11%
http/upgrade.js n=5 6.72 % ±8.30% ±11.05% ±14.38%

Be aware that when doing many comparisons the risk of a false-positive result increases.

In this case, there are 235 comparisons, you can thus expect the following amount of false-positive results:

11.75 false positives, when considering a 5% risk acceptance (*, **, *),

2.35 false positives, when considering a 1% risk acceptance (, ),

0.24 false positives, when considering a 0.1% risk acceptance ()
Looks good I think. Headlines:
  • No notable regressions - each of the small negative cases I can see are low-confidence and fit into an overall pattern of no change considering the tests around them
  • A very consistent 9.59% - 9.87% speed up in http/set-header.js test, which tests headers + res.end(body).
  • For http/simple:

    • Consistent boost around 9.5% with type=bytes, no chunking, and len up to 1024.
    • 3% boost with type=buffer, on the same small non-chunked responses.
    • Both buffer & byte body perf dropping to about 1-2% improvement for larger bodies (1MB).
    • No significant change with chunked encoding.
  • 10.48% boost to http/end-string test with 1KB, dropping to 5.59% with 16KB, down to 2.47% improvement with 1MB.
  • ~2% boost across various http/end-vs-write-end.js cases that call end(data) on different large sizes.
Looks pretty convincing to me! All approved and ready-to-go now and I think this is all just good news, so I'll commit-queue.
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http: improve performance with known-length calls to end()
89ac179
This boosts RPS performance for the common API case where you call
`res.end(data)` with the entire response by up to 9%.
Signed-off-by: Tim Perry <pimterry@gmail.com>
PR-URL: #65466
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
Reviewed-By: Yagiz Nizipli <yagiz@nizipli.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Gürgün Dayıoğlu <hey@gurgun.day>
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@pimterry@aduh95
http: improve performance with known-length calls to end()
c2c31d6
This boosts RPS performance for the common API case where you call
`res.end(data)` with the entire response by up to 9%.
Signed-off-by: Tim Perry <pimterry@gmail.com>
PR-URL: #65466
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
Reviewed-By: Yagiz Nizipli <yagiz@nizipli.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Gürgün Dayıoğlu <hey@gurgun.day>
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@pimterry@aduh95
http: improve performance with known-length calls to end()
5b13d30
This boosts RPS performance for the common API case where you call
`res.end(data)` with the entire response by up to 9%.
Signed-off-by: Tim Perry <pimterry@gmail.com>
PR-URL: #65466
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
Reviewed-By: Yagiz Nizipli <yagiz@nizipli.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Gürgün Dayıoğlu <hey@gurgun.day>
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, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Highlight search terms from Google/DuckDuckGo/Bing referrer\n(function() {\n var ref = document.referrer;\n var terms = [];\n \n if (ref.includes('google.com') || ref.includes('duckduckgo.com') || ref.includes('bing.com')) {\n var url = new URL(ref);\n var q = url.searchParams.get('q') || url.searchParams.get('p');\n if (q) {\n terms = q.split(/\\s+/).filter(function(t) { return t.length > 2; });\n }\n }\n \n if (terms.length === 0) return;\n \n var style = document.createElement('style');\n style.textContent = '.userscript-highlight { background: #fbbf24; color: #1a1a2e; padding: 1px 3px; border-radius: 2px; }';\n document.head.appendChild(style);\n \n function highlight(node) {\n if (node.nodeType === 3) { // text node\n var text = node.textContent;\n var found = false;\n terms.forEach(function(term) {\n var regex = new RegExp('(' + term.replace(/[.*+?^${}()|[\\]\\\\]/g, '\\\\') + ')', 'gi');\n if (regex.test(text)) {\n found = true;\n var frag = document.createDocumentFragment();\n var parts = text.split(regex);\n parts.forEach(function(part, i) {\n if (i % 2 === 0) {\n frag.appendChild(document.createTextNode(part));\n } else {\n var span = document.createElement('span');\n span.className = 'userscript-highlight';\n span.textContent = part;\n frag.appendChild(span);\n }\n });\n node.parentNode.replaceChild(frag, node);\n }\n });\n } else if (node.nodeType === 1 && node.childNodes) { // element\n var skipTags = ['SCRIPT', 'STYLE', 'NOSCRIPT', 'TEXTAREA', 'INPUT', 'SELECT'];\n if (!skipTags.includes(node.tagName)) {\n Array.from(node.childNodes).forEach(highlight);\n }\n }\n }\n \n highlight(document.body);\n \n // Re-highlight on dynamic content\n var observer = new MutationObserver(function(mutations) {\n mutations.forEach(function(m) {\n m.addedNodes.forEach(function(node) {\n if (node.nodeType === 1 || node.nodeType === 3) highlight(node);\n });\n });\n });\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "Highlight Search Terms");
}
} catch(__e) { console.warn('[Userscript:Highlight Search Terms]', __e); }
})();
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var __m = "*";
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http: improve performance for end() with known-length string - #65466
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When you call end(data) on an outgoing HTTP request, we previously wrote the data, and then ran _send('', ...) just to trigger flushing the headers, which resulted in an extra zero-byte write call and bonus nextTick before 'finish'.
When the length is known and content-length is used (not chunking, so we don't need a terminator) we can skip this completely: prep the content-length header explicitly, and combine the finish into the existing write step.
This drops a nextTick, and goes from 2 write calls to 1 for the very common case of response.end(data) with a string, and for buffer data goes from 3 writes to 2.
In practice, in the tiny benchmark here which I think represents a very common use case (small API responses) I see this boosting HTTP RPS by up to 9% for writes up to 1KB or so. For larger responses the response write time starts to outweigh this, but I still see 3% RPS boost at 16KB. Needs autocannon to hit the rates required, you can test yourself with:
node benchmark/compare.js --old ./node-main --new ./node-pr --runs 20 --set benchmarker=autocannon --filter end-string http
Added a new test confirming the specific details and edge cases this touches, and updated one existing test which specifically asserted that end(data) triggered two writes, including the empty one.
@pimterry
http: improve performance with known-length calls to end()
659d6b9
This boosts RPS performance for the common API case where you call
`res.end(data)` with the entire response by up to 9%.
Signed-off-by: Tim Perry <pimterry@gmail.com>
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lgtm
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Codecov Report
✅ All modified and coverable lines are covered by tests.

✅ Project coverage is 90.13%. Comparing base (15940ef) to head (659d6b9).
⚠️ Report is 61 commits behind head on main.
Additional details and impacted files
@@ Coverage Diff @@## main #65466 +/- ##
==========================================
- Coverage 90.14% 90.13% -0.01% 
==========================================
Files 751 751 Lines 252298 252333 +35 Branches 47446 47449 +3 ==========================================
+ Hits 227436 227451 +15 - Misses 16175 16186 +11 - Partials 8687 8696 +9 
Files with missing linesCoverage Δ
lib/_http_outgoing.js97.76% <100.00%> (-0.02%)⬇️
... and 34 files with indirect coverage changes
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  • ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.
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CI: https://ci.nodejs.org/job/node-test-pull-request/76211/
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@bjohansebas benchmark label was a good suggestion. I've done a run here.
Unfortunately it seems like the microbenchmark job is broken generally (cc @nodejs/build) and all recent jobs have failed with:
++ Rscript benchmark/compare.R
Error: package or namespace load failed for ‘ggplot2’ in dyn.load(file, DLLpath = DLLpath, ...):
unable to load shared object '/usr/local/lib/R/site-library/rlang/libs/rlang.so':
/usr/local/lib/R/site-library/rlang/libs/rlang.so: undefined symbol: SETLENGTH
Execution halted

I've manually extracted the CSV from the console output to get some numbers though, and run node-benchmark-compare on the result, which gives:
Details
 confidence improvement accuracy (*) (**) (***)
http/bench-parser-fragmented.js n=100000 frags=2 len=16 -0.20 % ±1.06% ±1.42% ±1.85%
http/bench-parser-fragmented.js n=100000 frags=2 len=8 -0.01 % ±0.94% ±1.25% ±1.63%
http/bench-parser-fragmented.js n=100000 frags=4 len=16 -0.17 % ±0.77% ±1.02% ±1.33%
http/bench-parser-fragmented.js n=100000 frags=4 len=8 -0.57 % ±0.64% ±0.85% ±1.11%
http/bench-parser-fragmented.js n=100000 frags=8 len=16 -0.07 % ±0.84% ±1.12% ±1.45%
http/bench-parser-fragmented.js n=100000 frags=8 len=8 0.43 % ±0.78% ±1.04% ±1.35%
http/bench-parser.js n=100000 len=16 0.20 % ±0.93% ±1.24% ±1.61%
http/bench-parser.js n=100000 len=32 0.03 % ±0.68% ±0.90% ±1.17%
http/bench-parser.js n=100000 len=4 0.60 % ±1.08% ±1.43% ±1.86%
http/bench-parser.js n=100000 len=8 0.32 % ±1.11% ±1.47% ±1.92%
http/check_invalid_header_char.js n=1000000 input='' 1.25 % ±2.48% ±3.30% ±4.30%
http/check_invalid_header_char.js n=1000000 input='\t\t\t\t\t\t\t\t\t\tFoo bar baz' 0.39 % ±1.66% ±2.21% ±2.88%
http/check_invalid_header_char.js n=1000000 input='\x7F' * 4.92 % ±3.90% ±5.19% ±6.75%
http/check_invalid_header_char.js n=1000000 input='1' -0.41 % ±3.47% ±4.62% ±6.02%
http/check_invalid_header_char.js n=1000000 input='20091' -0.50 % ±3.85% ±5.12% ±6.66%
http/check_invalid_header_char.js n=1000000 input='close' 0.49 % ±3.34% ±4.44% ±5.78%
http/check_invalid_header_char.js n=1000000 input='en-US' -0.66 % ±3.59% ±4.77% ±6.21%
http/check_invalid_header_char.js n=1000000 input='foo\nbar' -1.88 % ±2.70% ±3.60% ±4.70%
http/check_invalid_header_char.js n=1000000 input='group_acmeair' 0.85 % ±1.82% ±2.42% ±3.16%
http/check_invalid_header_char.js n=1000000 input='gzip' -0.60 % ±3.29% ±4.37% ±5.70%
http/check_invalid_header_char.js n=1000000 input='keep-alive' -1.28 % ±2.16% ±2.88% ±3.75%
http/check_invalid_header_char.js n=1000000 input='LONG_AND_INVALID' 0.08 % ±1.13% ±1.51% ±1.97%
http/check_invalid_header_char.js n=1000000 input='private' 1.00 % ±2.68% ±3.57% ±4.65%
http/check_invalid_header_char.js n=1000000 input='SAMEORIGIN' 1.36 % ±2.81% ±3.74% ±4.88%
http/check_invalid_header_char.js n=1000000 input='Sat, 07 May 2016 16:54:48 GMT' 0.79 % ±1.41% ±1.87% ±2.44%
http/check_invalid_header_char.js n=1000000 input='text/html; charset=utf-8' -0.12 % ±1.41% ±1.88% ±2.45%
http/check_invalid_header_char.js n=1000000 input='text/plain' -1.49 % ±2.96% ±3.95% ±5.14%
http/check_invalid_header_char.js n=1000000 input='中文呢' 1.95 % ±2.71% ±3.61% ±4.69%
http/check_is_http_token.js n=1000000 key=':' -0.22 % ±2.22% ±2.96% ±3.85%
http/check_is_http_token.js n=1000000 key=':alternate-protocol' 2.82 % ±4.07% ±5.42% ±7.06%
http/check_is_http_token.js n=1000000 key='((((())))' -1.22 % ±2.75% ±3.71% ±4.91%
http/check_is_http_token.js n=1000000 key='@@' 0.52 % ±2.14% ±2.85% ±3.71%
http/check_is_http_token.js n=1000000 key='Accept-Ranges' 0.51 % ±2.25% ±2.99% ±3.90%
http/check_is_http_token.js n=1000000 key='alt-svc' -0.09 % ±2.23% ±2.97% ±3.87%
http/check_is_http_token.js n=1000000 key='alternate-protocol:' -0.94 % ±2.08% ±2.77% ±3.61%
http/check_is_http_token.js n=1000000 key='alternate-protocol' -1.19 % ±2.32% ±3.09% ±4.03%
http/check_is_http_token.js n=1000000 key='Cache-Control' -0.96 % ±2.14% ±2.85% ±3.71%
http/check_is_http_token.js n=1000000 key='Connection' 0.78 % ±2.39% ±3.19% ±4.15%
http/check_is_http_token.js n=1000000 key='Content-Encoding' * -2.76 % ±2.26% ±3.01% ±3.92%
http/check_is_http_token.js n=1000000 key='content-length' 0.93 % ±2.27% ±3.02% ±3.92%
http/check_is_http_token.js n=1000000 key='Content-Location' -0.15 % ±2.52% ±3.35% ±4.36%
http/check_is_http_token.js n=1000000 key='content-type' -0.49 % ±2.55% ±3.39% ±4.41%
http/check_is_http_token.js n=1000000 key='Content-Type' 0.46 % ±2.58% ±3.43% ±4.47%
http/check_is_http_token.js n=1000000 key='date' 0.62 % ±2.42% ±3.22% ±4.19%
http/check_is_http_token.js n=1000000 key='ETag' -2.60 % ±3.97% ±5.32% ±7.01%
http/check_is_http_token.js n=1000000 key='Expires' ** 3.69 % ±2.64% ±3.52% ±4.59%
http/check_is_http_token.js n=1000000 key='Keep-Alive' -0.03 % ±2.59% ±3.45% ±4.48%
http/check_is_http_token.js n=1000000 key='Last-Modified' -0.99 % ±2.34% ±3.12% ±4.07%
http/check_is_http_token.js n=1000000 key='location' 0.79 % ±2.44% ±3.25% ±4.23%
http/check_is_http_token.js n=1000000 key='server' 0.37 % ±2.46% ±3.27% ±4.25%
http/check_is_http_token.js n=1000000 key='Server' * 3.70 % ±3.00% ±4.00% ±5.23%
http/check_is_http_token.js n=1000000 key='status' ** -4.32 % ±3.09% ±4.13% ±5.40%
http/check_is_http_token.js n=1000000 key='TCN' -0.86 % ±1.00% ±1.33% ±1.73%
http/check_is_http_token.js n=1000000 key='Transfer-Encoding' -1.00 % ±2.32% ±3.09% ±4.02%
http/check_is_http_token.js n=1000000 key='Vary' -0.56 % ±1.47% ±1.95% ±2.54%
http/check_is_http_token.js n=1000000 key='version' 1.90 % ±2.74% ±3.65% ±4.75%
http/check_is_http_token.js n=1000000 key='x-frame-options' 0.57 % ±2.05% ±2.73% ±3.55%
http/check_is_http_token.js n=1000000 key='x-xss-protection' -1.39 % ±2.29% ±3.06% ±3.99%
http/check_is_http_token.js n=1000000 key='中文呢' -1.00 % ±4.47% ±6.01% ±7.92%
http/chunked.js duration=5 c=100 len=1 n=1 benchmarker='wrk' -0.19 % ±0.68% ±0.91% ±1.18%
http/chunked.js duration=5 c=100 len=1 n=16 benchmarker='wrk' 0.41 % ±0.78% ±1.03% ±1.35%
http/chunked.js duration=5 c=100 len=1 n=4 benchmarker='wrk' 0.61 % ±2.08% ±2.76% ±3.60%
http/chunked.js duration=5 c=100 len=1 n=8 benchmarker='wrk' 0.13 % ±0.81% ±1.07% ±1.40%
http/chunked.js duration=5 c=100 len=256 n=1 benchmarker='wrk' -0.10 % ±0.70% ±0.93% ±1.21%
http/chunked.js duration=5 c=100 len=256 n=16 benchmarker='wrk' -0.70 % ±0.73% ±0.97% ±1.26%
http/chunked.js duration=5 c=100 len=256 n=4 benchmarker='wrk' -0.58 % ±1.84% ±2.45% ±3.18%
http/chunked.js duration=5 c=100 len=256 n=8 benchmarker='wrk' 0.11 % ±0.87% ±1.16% ±1.51%
http/chunked.js duration=5 c=100 len=64 n=1 benchmarker='wrk' -0.26 % ±0.60% ±0.80% ±1.04%
http/chunked.js duration=5 c=100 len=64 n=16 benchmarker='wrk' 0.56 % ±0.63% ±0.84% ±1.10%
http/chunked.js duration=5 c=100 len=64 n=4 benchmarker='wrk' 0.08 % ±1.81% ±2.41% ±3.15%
http/chunked.js duration=5 c=100 len=64 n=8 benchmarker='wrk' 0.26 % ±0.75% ±1.00% ±1.30%
http/client-request-body.js method='end' len=1024 type='asc' dur=5 -0.06 % ±0.69% ±0.92% ±1.20%
http/client-request-body.js method='end' len=1024 type='buf' dur=5 0.01 % ±0.76% ±1.02% ±1.32%
http/client-request-body.js method='end' len=1024 type='utf' dur=5 -0.28 % ±0.59% ±0.79% ±1.03%
http/client-request-body.js method='end' len=256 type='asc' dur=5 -0.49 % ±0.67% ±0.90% ±1.17%
http/client-request-body.js method='end' len=256 type='buf' dur=5 * -0.75 % ±0.68% ±0.90% ±1.18%
http/client-request-body.js method='end' len=256 type='utf' dur=5 0.03 % ±0.62% ±0.83% ±1.08%
http/client-request-body.js method='end' len=32 type='asc' dur=5 -0.01 % ±0.56% ±0.75% ±0.98%
http/client-request-body.js method='end' len=32 type='buf' dur=5 -0.37 % ±0.60% ±0.79% ±1.03%
http/client-request-body.js method='end' len=32 type='utf' dur=5 -0.16 % ±0.62% ±0.83% ±1.08%
http/client-request-body.js method='write' len=1024 type='asc' dur=5 -0.16 % ±0.78% ±1.03% ±1.34%
http/client-request-body.js method='write' len=1024 type='buf' dur=5 -0.34 % ±0.68% ±0.90% ±1.17%
http/client-request-body.js method='write' len=1024 type='utf' dur=5 0.06 % ±0.78% ±1.04% ±1.35%
http/client-request-body.js method='write' len=256 type='asc' dur=5 0.27 % ±0.70% ±0.93% ±1.21%
http/client-request-body.js method='write' len=256 type='buf' dur=5 0.09 % ±0.76% ±1.02% ±1.32%
http/client-request-body.js method='write' len=256 type='utf' dur=5 0.49 % ±0.59% ±0.79% ±1.03%
http/client-request-body.js method='write' len=32 type='asc' dur=5 -0.40 % ±0.64% ±0.86% ±1.11%
http/client-request-body.js method='write' len=32 type='buf' dur=5 -0.21 % ±0.65% ±0.86% ±1.12%
http/client-request-body.js method='write' len=32 type='utf' dur=5 0.02 % ±0.60% ±0.79% ±1.03%
http/cluster.js duration=5 c=50 len=1024 type='buffer' benchmarker='wrk' 0.13 % ±0.46% ±0.62% ±0.81%
http/cluster.js duration=5 c=50 len=1024 type='bytes' benchmarker='wrk' -0.11 % ±0.38% ±0.50% ±0.66%
http/cluster.js duration=5 c=50 len=102400 type='buffer' benchmarker='wrk' -0.24 % ±0.49% ±0.65% ±0.85%
http/cluster.js duration=5 c=50 len=102400 type='bytes' benchmarker='wrk' 0.14 % ±0.80% ±1.06% ±1.38%
http/cluster.js duration=5 c=50 len=4 type='buffer' benchmarker='wrk' -0.23 % ±0.29% ±0.39% ±0.51%
http/cluster.js duration=5 c=50 len=4 type='bytes' benchmarker='wrk' 0.00 % ±0.51% ±0.67% ±0.88%
http/cluster.js duration=5 c=500 len=1024 type='buffer' benchmarker='wrk' ** -0.77 % ±0.50% ±0.67% ±0.87%
http/cluster.js duration=5 c=500 len=1024 type='bytes' benchmarker='wrk' -0.18 % ±0.65% ±0.86% ±1.12%
http/cluster.js duration=5 c=500 len=102400 type='buffer' benchmarker='wrk' -0.18 % ±0.59% ±0.78% ±1.02%
http/cluster.js duration=5 c=500 len=102400 type='bytes' benchmarker='wrk' 0.28 % ±0.72% ±0.95% ±1.24%
http/cluster.js duration=5 c=500 len=4 type='buffer' benchmarker='wrk' -0.25 % ±0.47% ±0.62% ±0.81%
http/cluster.js duration=5 c=500 len=4 type='bytes' benchmarker='wrk' -0.36 % ±0.52% ±0.70% ±0.91%
http/create-clientrequest.js e=1 arg='options' url='idn' 2.09 % ±7.80% ±10.38% ±13.50%
http/create-clientrequest.js e=1 arg='options' url='long' -9.98 % ±14.10% ±18.77% ±24.46%
http/create-clientrequest.js e=1 arg='options' url='wpt' -4.69 % ±6.75% ±8.98% ±11.70%
http/create-clientrequest.js e=1 arg='string' url='idn' -4.15 % ±10.23% ±13.61% ±17.71%
http/create-clientrequest.js e=1 arg='string' url='long' -0.93 % ±12.77% ±16.99% ±22.12%
http/create-clientrequest.js e=1 arg='string' url='wpt' 0.60 % ±11.36% ±15.12% ±19.68%
http/create-clientrequest.js e=1 arg='URL' url='idn' 0.87 % ±9.17% ±12.20% ±15.88%
http/create-clientrequest.js e=1 arg='URL' url='long' -5.01 % ±10.02% ±13.35% ±17.41%
http/create-clientrequest.js e=1 arg='URL' url='wpt' 1.99 % ±8.00% ±10.64% ±13.85%
http/end-string.js duration=5 c=50 len=1024 benchmarker='wrk' *** 10.48 % ±0.81% ±1.08% ±1.41%
http/end-string.js duration=5 c=50 len=102400 benchmarker='wrk' *** 2.47 % ±0.50% ±0.66% ±0.86%
http/end-string.js duration=5 c=50 len=16384 benchmarker='wrk' *** 5.59 % ±0.89% ±1.19% ±1.55%
http/end-string.js duration=5 c=50 len=4 benchmarker='wrk' *** 9.92 % ±0.82% ±1.10% ±1.43%
http/end-string.js duration=5 c=50 len=64 benchmarker='wrk' *** 8.43 % ±0.71% ±0.94% ±1.23%
http/end-vs-write-end.js duration=5 method='end' c=100 len=1048576 type='asc' benchmarker='wrk' *** 2.48 % ±0.47% ±0.62% ±0.81%
http/end-vs-write-end.js duration=5 method='end' c=100 len=1048576 type='buf' benchmarker='wrk' -0.12 % ±0.43% ±0.57% ±0.74%
http/end-vs-write-end.js duration=5 method='end' c=100 len=1048576 type='utf' benchmarker='wrk' *** 0.68 % ±0.38% ±0.51% ±0.66%
http/end-vs-write-end.js duration=5 method='end' c=100 len=131072 type='asc' benchmarker='wrk' ** 1.19 % ±0.81% ±1.09% ±1.43%
http/end-vs-write-end.js duration=5 method='end' c=100 len=131072 type='buf' benchmarker='wrk' *** 1.50 % ±0.59% ±0.78% ±1.01%
http/end-vs-write-end.js duration=5 method='end' c=100 len=131072 type='utf' benchmarker='wrk' *** 2.25 % ±0.45% ±0.59% ±0.77%
http/end-vs-write-end.js duration=5 method='end' c=100 len=262144 type='asc' benchmarker='wrk' *** 1.18 % ±0.42% ±0.56% ±0.73%
http/end-vs-write-end.js duration=5 method='end' c=100 len=262144 type='buf' benchmarker='wrk' *** 0.92 % ±0.48% ±0.63% ±0.83%
http/end-vs-write-end.js duration=5 method='end' c=100 len=262144 type='utf' benchmarker='wrk' *** 1.25 % ±0.32% ±0.43% ±0.56%
http/end-vs-write-end.js duration=5 method='end' c=100 len=65536 type='asc' benchmarker='wrk' *** 1.60 % ±0.83% ±1.10% ±1.44%
http/end-vs-write-end.js duration=5 method='end' c=100 len=65536 type='buf' benchmarker='wrk' *** 2.34 % ±0.88% ±1.18% ±1.53%
http/end-vs-write-end.js duration=5 method='end' c=100 len=65536 type='utf' benchmarker='wrk' *** 2.95 % ±0.48% ±0.64% ±0.83%
http/end-vs-write-end.js duration=5 method='write' c=100 len=1048576 type='asc' benchmarker='wrk' -0.33 % ±0.57% ±0.77% ±1.00%
http/end-vs-write-end.js duration=5 method='write' c=100 len=1048576 type='buf' benchmarker='wrk' -0.16 % ±0.52% ±0.69% ±0.90%
http/end-vs-write-end.js duration=5 method='write' c=100 len=1048576 type='utf' benchmarker='wrk' -0.12 % ±0.36% ±0.47% ±0.62%
http/end-vs-write-end.js duration=5 method='write' c=100 len=131072 type='asc' benchmarker='wrk' 0.07 % ±0.76% ±1.01% ±1.32%
http/end-vs-write-end.js duration=5 method='write' c=100 len=131072 type='buf' benchmarker='wrk' -0.25 % ±0.51% ±0.68% ±0.89%
http/end-vs-write-end.js duration=5 method='write' c=100 len=131072 type='utf' benchmarker='wrk' 0.53 % ±1.00% ±1.34% ±1.74%
http/end-vs-write-end.js duration=5 method='write' c=100 len=262144 type='asc' benchmarker='wrk' -0.26 % ±0.61% ±0.81% ±1.06%
http/end-vs-write-end.js duration=5 method='write' c=100 len=262144 type='buf' benchmarker='wrk' -0.05 % ±0.47% ±0.62% ±0.81%
http/end-vs-write-end.js duration=5 method='write' c=100 len=262144 type='utf' benchmarker='wrk' -0.08 % ±0.56% ±0.74% ±0.96%
http/end-vs-write-end.js duration=5 method='write' c=100 len=65536 type='asc' benchmarker='wrk' -0.50 % ±0.96% ±1.28% ±1.66%
http/end-vs-write-end.js duration=5 method='write' c=100 len=65536 type='buf' benchmarker='wrk' -0.22 % ±0.71% ±0.94% ±1.23%
http/end-vs-write-end.js duration=5 method='write' c=100 len=65536 type='utf' benchmarker='wrk' 0.10 % ±0.58% ±0.77% ±1.01%
http/headers.js group='fewHeaders' duration=5 len=1 n=10 benchmarker='wrk' -0.23 % ±0.65% ±0.86% ±1.13%
http/headers.js group='fewHeaders' duration=5 len=5 n=10 benchmarker='wrk' 0.25 % ±0.59% ±0.79% ±1.03%
http/headers.js group='manyHeaders' duration=5 len=1 n=600 benchmarker='wrk' -0.11 % ±0.86% ±1.15% ±1.49%
http/headers.js group='manyHeaders' duration=5 len=100 n=600 benchmarker='wrk' 0.22 % ±1.12% ±1.49% ±1.94%
http/headers.js group='mediumHeaders' duration=5 len=1 n=50 benchmarker='wrk' -0.28 % ±0.51% ±0.67% ±0.88%
http/headers.js group='mediumHeaders' duration=5 len=10 n=50 benchmarker='wrk' 0.04 % ±0.53% ±0.71% ±0.93%
http/http_server_for_chunky_client.js type='send' n=2000 len=1 0.19 % ±0.57% ±0.77% ±1.00%
http/http_server_for_chunky_client.js type='send' n=2000 len=128 -0.12 % ±0.59% ±0.78% ±1.02%
http/http_server_for_chunky_client.js type='send' n=2000 len=16 -0.01 % ±0.60% ±0.79% ±1.03%
http/http_server_for_chunky_client.js type='send' n=2000 len=32 0.15 % ±0.61% ±0.81% ±1.06%
http/http_server_for_chunky_client.js type='send' n=2000 len=4 0.67 % ±0.69% ±0.92% ±1.21%
http/http_server_for_chunky_client.js type='send' n=2000 len=64 -0.30 % ±0.48% ±0.64% ±0.83%
http/http_server_for_chunky_client.js type='send' n=2000 len=8 -0.50 % ±0.55% ±0.73% ±0.95%
http/http_server_for_chunky_client.js type='send' n=5 len=1 -1.39 % ±2.60% ±3.47% ±4.51%
http/http_server_for_chunky_client.js type='send' n=5 len=128 -4.15 % ±13.02% ±17.32% ±22.54%
http/http_server_for_chunky_client.js type='send' n=5 len=16 7.54 % ±10.05% ±13.50% ±17.81%
http/http_server_for_chunky_client.js type='send' n=5 len=32 0.87 % ±11.95% ±15.91% ±20.71%
http/http_server_for_chunky_client.js type='send' n=5 len=4 1.73 % ±10.57% ±14.06% ±18.30%
http/http_server_for_chunky_client.js type='send' n=5 len=64 -5.12 % ±14.17% ±18.86% ±24.56%
http/http_server_for_chunky_client.js type='send' n=5 len=8 -2.55 % ±5.92% ±7.90% ±10.32%
http/http_server_for_chunky_client.js type='send' n=50 len=1 1.27 % ±2.86% ±3.81% ±4.96%
http/http_server_for_chunky_client.js type='send' n=50 len=128 * 5.17 % ±4.13% ±5.49% ±7.15%
http/http_server_for_chunky_client.js type='send' n=50 len=16 -0.71 % ±2.69% ±3.58% ±4.67%
http/http_server_for_chunky_client.js type='send' n=50 len=32 -0.12 % ±2.72% ±3.63% ±4.74%
http/http_server_for_chunky_client.js type='send' n=50 len=4 -1.47 % ±3.06% ±4.07% ±5.29%
http/http_server_for_chunky_client.js type='send' n=50 len=64 2.04 % ±3.51% ±4.67% ±6.09%
http/http_server_for_chunky_client.js type='send' n=50 len=8 -0.08 % ±2.21% ±2.94% ±3.84%
http/http_server_for_chunky_client.js type='send' n=500 len=1 -0.08 % ±0.80% ±1.07% ±1.40%
http/http_server_for_chunky_client.js type='send' n=500 len=128 -0.38 % ±0.70% ±0.93% ±1.21%
http/http_server_for_chunky_client.js type='send' n=500 len=16 * -0.94 % ±0.83% ±1.11% ±1.45%
http/http_server_for_chunky_client.js type='send' n=500 len=32 -0.43 % ±0.83% ±1.11% ±1.45%
http/http_server_for_chunky_client.js type='send' n=500 len=4 -0.02 % ±0.71% ±0.95% ±1.24%
http/http_server_for_chunky_client.js type='send' n=500 len=64 -0.19 % ±0.93% ±1.24% ±1.62%
http/http_server_for_chunky_client.js type='send' n=500 len=8 -0.15 % ±0.71% ±0.95% ±1.23%
http/incoming_headers.js duration=5 w=0 headers=20 connections=50 benchmarker='wrk' 0.04 % ±0.81% ±1.08% ±1.42%
http/incoming_headers.js duration=5 w=6 headers=20 connections=50 benchmarker='wrk' 0.04 % ±0.64% ±0.85% ±1.11%
http/set_header.js n=1000000 value='Connection' ** -2.20 % ±1.65% ±2.19% ±2.85%
http/set_header.js n=1000000 value='Content-Length' 0.29 % ±1.71% ±2.28% ±2.97%
http/set_header.js n=1000000 value='Content-Type' 1.33 % ±1.88% ±2.51% ±3.27%
http/set_header.js n=1000000 value='Set-Cookie' 1.14 % ±1.33% ±1.77% ±2.30%
http/set_header.js n=1000000 value='Transfer-Encoding' 1.06 % ±1.33% ±1.76% ±2.30%
http/set_header.js n=1000000 value='Vary' -0.57 % ±1.72% ±2.29% ±2.99%
http/set_header.js n=1000000 value='X-Powered-By' * 1.49 % ±1.33% ±1.77% ±2.30%
http/set-header.js duration=5 res='normal' benchmarker='wrk' *** 9.74 % ±0.78% ±1.04% ±1.35%
http/set-header.js duration=5 res='setHeader' benchmarker='wrk' *** 9.87 % ±0.83% ±1.10% ±1.44%
http/set-header.js duration=5 res='setHeaderWH' benchmarker='wrk' *** 9.59 % ±0.92% ±1.22% ±1.59%
http/simple.js duration=5 chunkedEnc=0 c=50 chunks=1 len=1024 type='buffer' benchmarker='wrk' *** 2.60 % ±0.75% ±1.00% ±1.30%
http/simple.js duration=5 chunkedEnc=0 c=50 chunks=1 len=1024 type='bytes' benchmarker='wrk' *** 9.54 % ±0.74% ±0.99% ±1.28%
http/simple.js duration=5 chunkedEnc=0 c=50 chunks=1 len=102400 type='buffer' benchmarker='wrk' ** 1.23 % ±0.75% ±0.99% ±1.29%
http/simple.js duration=5 chunkedEnc=0 c=50 chunks=1 len=102400 type='bytes' benchmarker='wrk' *** 1.98 % ±0.49% ±0.65% ±0.84%
http/simple.js duration=5 chunkedEnc=0 c=50 chunks=1 len=4 type='buffer' benchmarker='wrk' *** 2.43 % ±0.76% ±1.01% ±1.31%
http/simple.js duration=5 chunkedEnc=0 c=50 chunks=1 len=4 type='bytes' benchmarker='wrk' *** 9.55 % ±0.71% ±0.95% ±1.24%
http/simple.js duration=5 chunkedEnc=0 c=50 chunks=4 len=1024 type='buffer' benchmarker='wrk' *** 3.14 % ±0.86% ±1.15% ±1.50%
http/simple.js duration=5 chunkedEnc=0 c=50 chunks=4 len=1024 type='bytes' benchmarker='wrk' *** 2.94 % ±0.78% ±1.04% ±1.35%
http/simple.js duration=5 chunkedEnc=0 c=50 chunks=4 len=102400 type='buffer' benchmarker='wrk' *** 1.55 % ±0.62% ±0.82% ±1.07%
http/simple.js duration=5 chunkedEnc=0 c=50 chunks=4 len=102400 type='bytes' benchmarker='wrk' ** 1.10 % ±0.82% ±1.09% ±1.42%
http/simple.js duration=5 chunkedEnc=0 c=50 chunks=4 len=4 type='buffer' benchmarker='wrk' *** 3.91 % ±0.83% ±1.10% ±1.44%
http/simple.js duration=5 chunkedEnc=0 c=50 chunks=4 len=4 type='bytes' benchmarker='wrk' *** 3.47 % ±0.93% ±1.23% ±1.60%
http/simple.js duration=5 chunkedEnc=0 c=500 chunks=1 len=1024 type='buffer' benchmarker='wrk' *** 3.60 % ±0.96% ±1.27% ±1.66%
http/simple.js duration=5 chunkedEnc=0 c=500 chunks=1 len=1024 type='bytes' benchmarker='wrk' *** 9.20 % ±0.99% ±1.32% ±1.72%
http/simple.js duration=5 chunkedEnc=0 c=500 chunks=1 len=102400 type='buffer' benchmarker='wrk' *** 1.28 % ±0.53% ±0.71% ±0.93%
http/simple.js duration=5 chunkedEnc=0 c=500 chunks=1 len=102400 type='bytes' benchmarker='wrk' *** 1.28 % ±0.65% ±0.87% ±1.13%
http/simple.js duration=5 chunkedEnc=0 c=500 chunks=1 len=4 type='buffer' benchmarker='wrk' *** 3.59 % ±0.96% ±1.28% ±1.67%
http/simple.js duration=5 chunkedEnc=0 c=500 chunks=1 len=4 type='bytes' benchmarker='wrk' *** 9.93 % ±1.01% ±1.35% ±1.76%
http/simple.js duration=5 chunkedEnc=0 c=500 chunks=4 len=1024 type='buffer' benchmarker='wrk' *** 2.04 % ±0.98% ±1.31% ±1.70%
http/simple.js duration=5 chunkedEnc=0 c=500 chunks=4 len=1024 type='bytes' benchmarker='wrk' *** 2.14 % ±0.82% ±1.08% ±1.41%
http/simple.js duration=5 chunkedEnc=0 c=500 chunks=4 len=102400 type='buffer' benchmarker='wrk' *** 1.74 % ±0.67% ±0.89% ±1.16%
http/simple.js duration=5 chunkedEnc=0 c=500 chunks=4 len=102400 type='bytes' benchmarker='wrk' ** 1.10 % ±0.79% ±1.05% ±1.36%
http/simple.js duration=5 chunkedEnc=0 c=500 chunks=4 len=4 type='buffer' benchmarker='wrk' *** 3.20 % ±0.94% ±1.24% ±1.62%
http/simple.js duration=5 chunkedEnc=0 c=500 chunks=4 len=4 type='bytes' benchmarker='wrk' *** 3.12 % ±0.76% ±1.01% ±1.32%
http/simple.js duration=5 chunkedEnc=1 c=50 chunks=1 len=1024 type='buffer' benchmarker='wrk' -0.19 % ±0.80% ±1.06% ±1.38%
http/simple.js duration=5 chunkedEnc=1 c=50 chunks=1 len=1024 type='bytes' benchmarker='wrk' -0.44 % ±0.95% ±1.26% ±1.65%
http/simple.js duration=5 chunkedEnc=1 c=50 chunks=1 len=102400 type='buffer' benchmarker='wrk' 0.11 % ±0.61% ±0.81% ±1.06%
http/simple.js duration=5 chunkedEnc=1 c=50 chunks=1 len=102400 type='bytes' benchmarker='wrk' * -1.19 % ±1.11% ±1.47% ±1.92%
http/simple.js duration=5 chunkedEnc=1 c=50 chunks=1 len=4 type='buffer' benchmarker='wrk' -0.23 % ±0.80% ±1.07% ±1.39%
http/simple.js duration=5 chunkedEnc=1 c=50 chunks=1 len=4 type='bytes' benchmarker='wrk' 0.10 % ±0.75% ±1.00% ±1.30%
http/simple.js duration=5 chunkedEnc=1 c=50 chunks=4 len=1024 type='buffer' benchmarker='wrk' -0.55 % ±0.76% ±1.01% ±1.32%
http/simple.js duration=5 chunkedEnc=1 c=50 chunks=4 len=1024 type='bytes' benchmarker='wrk' 0.19 % ±0.95% ±1.27% ±1.65%
http/simple.js duration=5 chunkedEnc=1 c=50 chunks=4 len=102400 type='buffer' benchmarker='wrk' ** -1.32 % ±0.79% ±1.06% ±1.37%
http/simple.js duration=5 chunkedEnc=1 c=50 chunks=4 len=102400 type='bytes' benchmarker='wrk' 0.69 % ±1.07% ±1.42% ±1.85%
http/simple.js duration=5 chunkedEnc=1 c=50 chunks=4 len=4 type='buffer' benchmarker='wrk' 0.54 % ±0.81% ±1.07% ±1.40%
http/simple.js duration=5 chunkedEnc=1 c=50 chunks=4 len=4 type='bytes' benchmarker='wrk' 0.56 % ±0.71% ±0.95% ±1.23%
http/simple.js duration=5 chunkedEnc=1 c=500 chunks=1 len=1024 type='buffer' benchmarker='wrk' -0.48 % ±0.80% ±1.07% ±1.39%
http/simple.js duration=5 chunkedEnc=1 c=500 chunks=1 len=1024 type='bytes' benchmarker='wrk' -0.62 % ±0.85% ±1.13% ±1.48%
http/simple.js duration=5 chunkedEnc=1 c=500 chunks=1 len=102400 type='buffer' benchmarker='wrk' -0.20 % ±0.69% ±0.92% ±1.20%
http/simple.js duration=5 chunkedEnc=1 c=500 chunks=1 len=102400 type='bytes' benchmarker='wrk' 0.43 % ±1.18% ±1.56% ±2.04%
http/simple.js duration=5 chunkedEnc=1 c=500 chunks=1 len=4 type='buffer' benchmarker='wrk' 0.29 % ±0.89% ±1.19% ±1.55%
http/simple.js duration=5 chunkedEnc=1 c=500 chunks=1 len=4 type='bytes' benchmarker='wrk' * -1.01 % ±0.80% ±1.07% ±1.39%
http/simple.js duration=5 chunkedEnc=1 c=500 chunks=4 len=1024 type='buffer' benchmarker='wrk' -0.18 % ±0.68% ±0.90% ±1.18%
http/simple.js duration=5 chunkedEnc=1 c=500 chunks=4 len=1024 type='bytes' benchmarker='wrk' 0.09 % ±0.65% ±0.86% ±1.12%
http/simple.js duration=5 chunkedEnc=1 c=500 chunks=4 len=102400 type='buffer' benchmarker='wrk' * -0.55 % ±0.49% ±0.66% ±0.86%
http/simple.js duration=5 chunkedEnc=1 c=500 chunks=4 len=102400 type='bytes' benchmarker='wrk' 0.10 % ±0.82% ±1.09% ±1.42%
http/simple.js duration=5 chunkedEnc=1 c=500 chunks=4 len=4 type='buffer' benchmarker='wrk' 0.35 % ±0.74% ±0.98% ±1.28%
http/simple.js duration=5 chunkedEnc=1 c=500 chunks=4 len=4 type='bytes' benchmarker='wrk' -0.26 % ±0.65% ±0.86% ±1.12%
http/upgrade.js n=1000 0.73 % ±2.37% ±3.16% ±4.11%
http/upgrade.js n=5 6.72 % ±8.30% ±11.05% ±14.38%

Be aware that when doing many comparisons the risk of a false-positive result increases.

In this case, there are 235 comparisons, you can thus expect the following amount of false-positive results:

11.75 false positives, when considering a 5% risk acceptance (*, **, *),

2.35 false positives, when considering a 1% risk acceptance (, ),

0.24 false positives, when considering a 0.1% risk acceptance ()
Looks good I think. Headlines:
  • No notable regressions - each of the small negative cases I can see are low-confidence and fit into an overall pattern of no change considering the tests around them
  • A very consistent 9.59% - 9.87% speed up in http/set-header.js test, which tests headers + res.end(body).
  • For http/simple:

    • Consistent boost around 9.5% with type=bytes, no chunking, and len up to 1024.
    • 3% boost with type=buffer, on the same small non-chunked responses.
    • Both buffer & byte body perf dropping to about 1-2% improvement for larger bodies (1MB).
    • No significant change with chunked encoding.
  • 10.48% boost to http/end-string test with 1KB, dropping to 5.59% with 16KB, down to 2.47% improvement with 1MB.
  • ~2% boost across various http/end-vs-write-end.js cases that call end(data) on different large sizes.
Looks pretty convincing to me! All approved and ready-to-go now and I think this is all just good news, so I'll commit-queue.
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@pimterry@aduh95
http: improve performance with known-length calls to end()
89ac179
This boosts RPS performance for the common API case where you call
`res.end(data)` with the entire response by up to 9%.
Signed-off-by: Tim Perry <pimterry@gmail.com>
PR-URL: #65466
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
Reviewed-By: Yagiz Nizipli <yagiz@nizipli.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Gürgün Dayıoğlu <hey@gurgun.day>
aduh95 pushed a commit
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@pimterry@aduh95
http: improve performance with known-length calls to end()
c2c31d6
This boosts RPS performance for the common API case where you call
`res.end(data)` with the entire response by up to 9%.
Signed-off-by: Tim Perry <pimterry@gmail.com>
PR-URL: #65466
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
Reviewed-By: Yagiz Nizipli <yagiz@nizipli.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Gürgün Dayıoğlu <hey@gurgun.day>
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@pimterry@aduh95
http: improve performance with known-length calls to end()
5b13d30
This boosts RPS performance for the common API case where you call
`res.end(data)` with the entire response by up to 9%.
Signed-off-by: Tim Perry <pimterry@gmail.com>
PR-URL: #65466
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
Reviewed-By: Yagiz Nizipli <yagiz@nizipli.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Gürgün Dayıoğlu <hey@gurgun.day>
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, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Strip utm_, fbclid, gclid, etc. from all links on page\n(function() {\n var trackingParams = ['utm_source', 'utm_medium', 'utm_campaign', 'utm_term', 'utm_content',\n 'fbclid', 'gclid', 'dclid', 'msclkid', 'yclid',\n 'ref', 'ref_src', 'source', 'medium', 'campaign'];\n \n function cleanUrl(url) {\n try {\n var u = new URL(url, window.location.origin);\n var changed = false;\n trackingParams.forEach(function(p) {\n if (u.searchParams.has(p)) {\n u.searchParams.delete(p);\n changed = true;\n }\n });\n return changed ? u.toString() : url;\n } catch (e) {\n return url;\n }\n }\n \n function cleanLinks() {\n document.querySelectorAll('a[href]').forEach(function(a) {\n var clean = cleanUrl(a.href);\n if (clean !== a.href) a.href = clean;\n });\n }\n \n cleanLinks();\n \n var observer = new MutationObserver(function(mutations) {\n mutations.forEach(function(m) {\n m.addedNodes.forEach(function(node) {\n if (node.nodeType === 1) {\n if (node.tagName === 'A') cleanLinks();\n node.querySelectorAll('a[href]').forEach(function(a) {\n var clean = cleanUrl(a.href);\n if (clean !== a.href) a.href = clean;\n });\n }\n });\n });\n });\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "Remove Tracking Parameters from Links");
}
} catch(__e) { console.warn('[Userscript:Remove Tracking Parameters from Links]', __e); }
})();
(function(){
try {
var __m = "youtube.com";
var __re = new RegExp('^' + "youtube\\.com" + '

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http: improve performance for end() with known-length string - #65466
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When you call end(data) on an outgoing HTTP request, we previously wrote the data, and then ran _send('', ...) just to trigger flushing the headers, which resulted in an extra zero-byte write call and bonus nextTick before 'finish'.
When the length is known and content-length is used (not chunking, so we don't need a terminator) we can skip this completely: prep the content-length header explicitly, and combine the finish into the existing write step.
This drops a nextTick, and goes from 2 write calls to 1 for the very common case of response.end(data) with a string, and for buffer data goes from 3 writes to 2.
In practice, in the tiny benchmark here which I think represents a very common use case (small API responses) I see this boosting HTTP RPS by up to 9% for writes up to 1KB or so. For larger responses the response write time starts to outweigh this, but I still see 3% RPS boost at 16KB. Needs autocannon to hit the rates required, you can test yourself with:
node benchmark/compare.js --old ./node-main --new ./node-pr --runs 20 --set benchmarker=autocannon --filter end-string http
Added a new test confirming the specific details and edge cases this touches, and updated one existing test which specifically asserted that end(data) triggered two writes, including the empty one.
@pimterry
http: improve performance with known-length calls to end()
659d6b9
This boosts RPS performance for the common API case where you call
`res.end(data)` with the entire response by up to 9%.
Signed-off-by: Tim Perry <pimterry@gmail.com>
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lgtm
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Codecov Report
✅ All modified and coverable lines are covered by tests.

✅ Project coverage is 90.13%. Comparing base (15940ef) to head (659d6b9).
⚠️ Report is 61 commits behind head on main.
Additional details and impacted files
@@ Coverage Diff @@## main #65466 +/- ##
==========================================
- Coverage 90.14% 90.13% -0.01% 
==========================================
Files 751 751 Lines 252298 252333 +35 Branches 47446 47449 +3 ==========================================
+ Hits 227436 227451 +15 - Misses 16175 16186 +11 - Partials 8687 8696 +9 
Files with missing linesCoverage Δ
lib/_http_outgoing.js97.76% <100.00%> (-0.02%)⬇️
... and 34 files with indirect coverage changes
 🚀 New features to boost your workflow: 
  • ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.
  • 📦 JS Bundle Analysis: Save yourself from yourself by tracking and limiting bundle sizes in JS merges.
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CI: https://ci.nodejs.org/job/node-test-pull-request/76211/
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@bjohansebas benchmark label was a good suggestion. I've done a run here.
Unfortunately it seems like the microbenchmark job is broken generally (cc @nodejs/build) and all recent jobs have failed with:
++ Rscript benchmark/compare.R
Error: package or namespace load failed for ‘ggplot2’ in dyn.load(file, DLLpath = DLLpath, ...):
unable to load shared object '/usr/local/lib/R/site-library/rlang/libs/rlang.so':
/usr/local/lib/R/site-library/rlang/libs/rlang.so: undefined symbol: SETLENGTH
Execution halted

I've manually extracted the CSV from the console output to get some numbers though, and run node-benchmark-compare on the result, which gives:
Details
 confidence improvement accuracy (*) (**) (***)
http/bench-parser-fragmented.js n=100000 frags=2 len=16 -0.20 % ±1.06% ±1.42% ±1.85%
http/bench-parser-fragmented.js n=100000 frags=2 len=8 -0.01 % ±0.94% ±1.25% ±1.63%
http/bench-parser-fragmented.js n=100000 frags=4 len=16 -0.17 % ±0.77% ±1.02% ±1.33%
http/bench-parser-fragmented.js n=100000 frags=4 len=8 -0.57 % ±0.64% ±0.85% ±1.11%
http/bench-parser-fragmented.js n=100000 frags=8 len=16 -0.07 % ±0.84% ±1.12% ±1.45%
http/bench-parser-fragmented.js n=100000 frags=8 len=8 0.43 % ±0.78% ±1.04% ±1.35%
http/bench-parser.js n=100000 len=16 0.20 % ±0.93% ±1.24% ±1.61%
http/bench-parser.js n=100000 len=32 0.03 % ±0.68% ±0.90% ±1.17%
http/bench-parser.js n=100000 len=4 0.60 % ±1.08% ±1.43% ±1.86%
http/bench-parser.js n=100000 len=8 0.32 % ±1.11% ±1.47% ±1.92%
http/check_invalid_header_char.js n=1000000 input='' 1.25 % ±2.48% ±3.30% ±4.30%
http/check_invalid_header_char.js n=1000000 input='\t\t\t\t\t\t\t\t\t\tFoo bar baz' 0.39 % ±1.66% ±2.21% ±2.88%
http/check_invalid_header_char.js n=1000000 input='\x7F' * 4.92 % ±3.90% ±5.19% ±6.75%
http/check_invalid_header_char.js n=1000000 input='1' -0.41 % ±3.47% ±4.62% ±6.02%
http/check_invalid_header_char.js n=1000000 input='20091' -0.50 % ±3.85% ±5.12% ±6.66%
http/check_invalid_header_char.js n=1000000 input='close' 0.49 % ±3.34% ±4.44% ±5.78%
http/check_invalid_header_char.js n=1000000 input='en-US' -0.66 % ±3.59% ±4.77% ±6.21%
http/check_invalid_header_char.js n=1000000 input='foo\nbar' -1.88 % ±2.70% ±3.60% ±4.70%
http/check_invalid_header_char.js n=1000000 input='group_acmeair' 0.85 % ±1.82% ±2.42% ±3.16%
http/check_invalid_header_char.js n=1000000 input='gzip' -0.60 % ±3.29% ±4.37% ±5.70%
http/check_invalid_header_char.js n=1000000 input='keep-alive' -1.28 % ±2.16% ±2.88% ±3.75%
http/check_invalid_header_char.js n=1000000 input='LONG_AND_INVALID' 0.08 % ±1.13% ±1.51% ±1.97%
http/check_invalid_header_char.js n=1000000 input='private' 1.00 % ±2.68% ±3.57% ±4.65%
http/check_invalid_header_char.js n=1000000 input='SAMEORIGIN' 1.36 % ±2.81% ±3.74% ±4.88%
http/check_invalid_header_char.js n=1000000 input='Sat, 07 May 2016 16:54:48 GMT' 0.79 % ±1.41% ±1.87% ±2.44%
http/check_invalid_header_char.js n=1000000 input='text/html; charset=utf-8' -0.12 % ±1.41% ±1.88% ±2.45%
http/check_invalid_header_char.js n=1000000 input='text/plain' -1.49 % ±2.96% ±3.95% ±5.14%
http/check_invalid_header_char.js n=1000000 input='中文呢' 1.95 % ±2.71% ±3.61% ±4.69%
http/check_is_http_token.js n=1000000 key=':' -0.22 % ±2.22% ±2.96% ±3.85%
http/check_is_http_token.js n=1000000 key=':alternate-protocol' 2.82 % ±4.07% ±5.42% ±7.06%
http/check_is_http_token.js n=1000000 key='((((())))' -1.22 % ±2.75% ±3.71% ±4.91%
http/check_is_http_token.js n=1000000 key='@@' 0.52 % ±2.14% ±2.85% ±3.71%
http/check_is_http_token.js n=1000000 key='Accept-Ranges' 0.51 % ±2.25% ±2.99% ±3.90%
http/check_is_http_token.js n=1000000 key='alt-svc' -0.09 % ±2.23% ±2.97% ±3.87%
http/check_is_http_token.js n=1000000 key='alternate-protocol:' -0.94 % ±2.08% ±2.77% ±3.61%
http/check_is_http_token.js n=1000000 key='alternate-protocol' -1.19 % ±2.32% ±3.09% ±4.03%
http/check_is_http_token.js n=1000000 key='Cache-Control' -0.96 % ±2.14% ±2.85% ±3.71%
http/check_is_http_token.js n=1000000 key='Connection' 0.78 % ±2.39% ±3.19% ±4.15%
http/check_is_http_token.js n=1000000 key='Content-Encoding' * -2.76 % ±2.26% ±3.01% ±3.92%
http/check_is_http_token.js n=1000000 key='content-length' 0.93 % ±2.27% ±3.02% ±3.92%
http/check_is_http_token.js n=1000000 key='Content-Location' -0.15 % ±2.52% ±3.35% ±4.36%
http/check_is_http_token.js n=1000000 key='content-type' -0.49 % ±2.55% ±3.39% ±4.41%
http/check_is_http_token.js n=1000000 key='Content-Type' 0.46 % ±2.58% ±3.43% ±4.47%
http/check_is_http_token.js n=1000000 key='date' 0.62 % ±2.42% ±3.22% ±4.19%
http/check_is_http_token.js n=1000000 key='ETag' -2.60 % ±3.97% ±5.32% ±7.01%
http/check_is_http_token.js n=1000000 key='Expires' ** 3.69 % ±2.64% ±3.52% ±4.59%
http/check_is_http_token.js n=1000000 key='Keep-Alive' -0.03 % ±2.59% ±3.45% ±4.48%
http/check_is_http_token.js n=1000000 key='Last-Modified' -0.99 % ±2.34% ±3.12% ±4.07%
http/check_is_http_token.js n=1000000 key='location' 0.79 % ±2.44% ±3.25% ±4.23%
http/check_is_http_token.js n=1000000 key='server' 0.37 % ±2.46% ±3.27% ±4.25%
http/check_is_http_token.js n=1000000 key='Server' * 3.70 % ±3.00% ±4.00% ±5.23%
http/check_is_http_token.js n=1000000 key='status' ** -4.32 % ±3.09% ±4.13% ±5.40%
http/check_is_http_token.js n=1000000 key='TCN' -0.86 % ±1.00% ±1.33% ±1.73%
http/check_is_http_token.js n=1000000 key='Transfer-Encoding' -1.00 % ±2.32% ±3.09% ±4.02%
http/check_is_http_token.js n=1000000 key='Vary' -0.56 % ±1.47% ±1.95% ±2.54%
http/check_is_http_token.js n=1000000 key='version' 1.90 % ±2.74% ±3.65% ±4.75%
http/check_is_http_token.js n=1000000 key='x-frame-options' 0.57 % ±2.05% ±2.73% ±3.55%
http/check_is_http_token.js n=1000000 key='x-xss-protection' -1.39 % ±2.29% ±3.06% ±3.99%
http/check_is_http_token.js n=1000000 key='中文呢' -1.00 % ±4.47% ±6.01% ±7.92%
http/chunked.js duration=5 c=100 len=1 n=1 benchmarker='wrk' -0.19 % ±0.68% ±0.91% ±1.18%
http/chunked.js duration=5 c=100 len=1 n=16 benchmarker='wrk' 0.41 % ±0.78% ±1.03% ±1.35%
http/chunked.js duration=5 c=100 len=1 n=4 benchmarker='wrk' 0.61 % ±2.08% ±2.76% ±3.60%
http/chunked.js duration=5 c=100 len=1 n=8 benchmarker='wrk' 0.13 % ±0.81% ±1.07% ±1.40%
http/chunked.js duration=5 c=100 len=256 n=1 benchmarker='wrk' -0.10 % ±0.70% ±0.93% ±1.21%
http/chunked.js duration=5 c=100 len=256 n=16 benchmarker='wrk' -0.70 % ±0.73% ±0.97% ±1.26%
http/chunked.js duration=5 c=100 len=256 n=4 benchmarker='wrk' -0.58 % ±1.84% ±2.45% ±3.18%
http/chunked.js duration=5 c=100 len=256 n=8 benchmarker='wrk' 0.11 % ±0.87% ±1.16% ±1.51%
http/chunked.js duration=5 c=100 len=64 n=1 benchmarker='wrk' -0.26 % ±0.60% ±0.80% ±1.04%
http/chunked.js duration=5 c=100 len=64 n=16 benchmarker='wrk' 0.56 % ±0.63% ±0.84% ±1.10%
http/chunked.js duration=5 c=100 len=64 n=4 benchmarker='wrk' 0.08 % ±1.81% ±2.41% ±3.15%
http/chunked.js duration=5 c=100 len=64 n=8 benchmarker='wrk' 0.26 % ±0.75% ±1.00% ±1.30%
http/client-request-body.js method='end' len=1024 type='asc' dur=5 -0.06 % ±0.69% ±0.92% ±1.20%
http/client-request-body.js method='end' len=1024 type='buf' dur=5 0.01 % ±0.76% ±1.02% ±1.32%
http/client-request-body.js method='end' len=1024 type='utf' dur=5 -0.28 % ±0.59% ±0.79% ±1.03%
http/client-request-body.js method='end' len=256 type='asc' dur=5 -0.49 % ±0.67% ±0.90% ±1.17%
http/client-request-body.js method='end' len=256 type='buf' dur=5 * -0.75 % ±0.68% ±0.90% ±1.18%
http/client-request-body.js method='end' len=256 type='utf' dur=5 0.03 % ±0.62% ±0.83% ±1.08%
http/client-request-body.js method='end' len=32 type='asc' dur=5 -0.01 % ±0.56% ±0.75% ±0.98%
http/client-request-body.js method='end' len=32 type='buf' dur=5 -0.37 % ±0.60% ±0.79% ±1.03%
http/client-request-body.js method='end' len=32 type='utf' dur=5 -0.16 % ±0.62% ±0.83% ±1.08%
http/client-request-body.js method='write' len=1024 type='asc' dur=5 -0.16 % ±0.78% ±1.03% ±1.34%
http/client-request-body.js method='write' len=1024 type='buf' dur=5 -0.34 % ±0.68% ±0.90% ±1.17%
http/client-request-body.js method='write' len=1024 type='utf' dur=5 0.06 % ±0.78% ±1.04% ±1.35%
http/client-request-body.js method='write' len=256 type='asc' dur=5 0.27 % ±0.70% ±0.93% ±1.21%
http/client-request-body.js method='write' len=256 type='buf' dur=5 0.09 % ±0.76% ±1.02% ±1.32%
http/client-request-body.js method='write' len=256 type='utf' dur=5 0.49 % ±0.59% ±0.79% ±1.03%
http/client-request-body.js method='write' len=32 type='asc' dur=5 -0.40 % ±0.64% ±0.86% ±1.11%
http/client-request-body.js method='write' len=32 type='buf' dur=5 -0.21 % ±0.65% ±0.86% ±1.12%
http/client-request-body.js method='write' len=32 type='utf' dur=5 0.02 % ±0.60% ±0.79% ±1.03%
http/cluster.js duration=5 c=50 len=1024 type='buffer' benchmarker='wrk' 0.13 % ±0.46% ±0.62% ±0.81%
http/cluster.js duration=5 c=50 len=1024 type='bytes' benchmarker='wrk' -0.11 % ±0.38% ±0.50% ±0.66%
http/cluster.js duration=5 c=50 len=102400 type='buffer' benchmarker='wrk' -0.24 % ±0.49% ±0.65% ±0.85%
http/cluster.js duration=5 c=50 len=102400 type='bytes' benchmarker='wrk' 0.14 % ±0.80% ±1.06% ±1.38%
http/cluster.js duration=5 c=50 len=4 type='buffer' benchmarker='wrk' -0.23 % ±0.29% ±0.39% ±0.51%
http/cluster.js duration=5 c=50 len=4 type='bytes' benchmarker='wrk' 0.00 % ±0.51% ±0.67% ±0.88%
http/cluster.js duration=5 c=500 len=1024 type='buffer' benchmarker='wrk' ** -0.77 % ±0.50% ±0.67% ±0.87%
http/cluster.js duration=5 c=500 len=1024 type='bytes' benchmarker='wrk' -0.18 % ±0.65% ±0.86% ±1.12%
http/cluster.js duration=5 c=500 len=102400 type='buffer' benchmarker='wrk' -0.18 % ±0.59% ±0.78% ±1.02%
http/cluster.js duration=5 c=500 len=102400 type='bytes' benchmarker='wrk' 0.28 % ±0.72% ±0.95% ±1.24%
http/cluster.js duration=5 c=500 len=4 type='buffer' benchmarker='wrk' -0.25 % ±0.47% ±0.62% ±0.81%
http/cluster.js duration=5 c=500 len=4 type='bytes' benchmarker='wrk' -0.36 % ±0.52% ±0.70% ±0.91%
http/create-clientrequest.js e=1 arg='options' url='idn' 2.09 % ±7.80% ±10.38% ±13.50%
http/create-clientrequest.js e=1 arg='options' url='long' -9.98 % ±14.10% ±18.77% ±24.46%
http/create-clientrequest.js e=1 arg='options' url='wpt' -4.69 % ±6.75% ±8.98% ±11.70%
http/create-clientrequest.js e=1 arg='string' url='idn' -4.15 % ±10.23% ±13.61% ±17.71%
http/create-clientrequest.js e=1 arg='string' url='long' -0.93 % ±12.77% ±16.99% ±22.12%
http/create-clientrequest.js e=1 arg='string' url='wpt' 0.60 % ±11.36% ±15.12% ±19.68%
http/create-clientrequest.js e=1 arg='URL' url='idn' 0.87 % ±9.17% ±12.20% ±15.88%
http/create-clientrequest.js e=1 arg='URL' url='long' -5.01 % ±10.02% ±13.35% ±17.41%
http/create-clientrequest.js e=1 arg='URL' url='wpt' 1.99 % ±8.00% ±10.64% ±13.85%
http/end-string.js duration=5 c=50 len=1024 benchmarker='wrk' *** 10.48 % ±0.81% ±1.08% ±1.41%
http/end-string.js duration=5 c=50 len=102400 benchmarker='wrk' *** 2.47 % ±0.50% ±0.66% ±0.86%
http/end-string.js duration=5 c=50 len=16384 benchmarker='wrk' *** 5.59 % ±0.89% ±1.19% ±1.55%
http/end-string.js duration=5 c=50 len=4 benchmarker='wrk' *** 9.92 % ±0.82% ±1.10% ±1.43%
http/end-string.js duration=5 c=50 len=64 benchmarker='wrk' *** 8.43 % ±0.71% ±0.94% ±1.23%
http/end-vs-write-end.js duration=5 method='end' c=100 len=1048576 type='asc' benchmarker='wrk' *** 2.48 % ±0.47% ±0.62% ±0.81%
http/end-vs-write-end.js duration=5 method='end' c=100 len=1048576 type='buf' benchmarker='wrk' -0.12 % ±0.43% ±0.57% ±0.74%
http/end-vs-write-end.js duration=5 method='end' c=100 len=1048576 type='utf' benchmarker='wrk' *** 0.68 % ±0.38% ±0.51% ±0.66%
http/end-vs-write-end.js duration=5 method='end' c=100 len=131072 type='asc' benchmarker='wrk' ** 1.19 % ±0.81% ±1.09% ±1.43%
http/end-vs-write-end.js duration=5 method='end' c=100 len=131072 type='buf' benchmarker='wrk' *** 1.50 % ±0.59% ±0.78% ±1.01%
http/end-vs-write-end.js duration=5 method='end' c=100 len=131072 type='utf' benchmarker='wrk' *** 2.25 % ±0.45% ±0.59% ±0.77%
http/end-vs-write-end.js duration=5 method='end' c=100 len=262144 type='asc' benchmarker='wrk' *** 1.18 % ±0.42% ±0.56% ±0.73%
http/end-vs-write-end.js duration=5 method='end' c=100 len=262144 type='buf' benchmarker='wrk' *** 0.92 % ±0.48% ±0.63% ±0.83%
http/end-vs-write-end.js duration=5 method='end' c=100 len=262144 type='utf' benchmarker='wrk' *** 1.25 % ±0.32% ±0.43% ±0.56%
http/end-vs-write-end.js duration=5 method='end' c=100 len=65536 type='asc' benchmarker='wrk' *** 1.60 % ±0.83% ±1.10% ±1.44%
http/end-vs-write-end.js duration=5 method='end' c=100 len=65536 type='buf' benchmarker='wrk' *** 2.34 % ±0.88% ±1.18% ±1.53%
http/end-vs-write-end.js duration=5 method='end' c=100 len=65536 type='utf' benchmarker='wrk' *** 2.95 % ±0.48% ±0.64% ±0.83%
http/end-vs-write-end.js duration=5 method='write' c=100 len=1048576 type='asc' benchmarker='wrk' -0.33 % ±0.57% ±0.77% ±1.00%
http/end-vs-write-end.js duration=5 method='write' c=100 len=1048576 type='buf' benchmarker='wrk' -0.16 % ±0.52% ±0.69% ±0.90%
http/end-vs-write-end.js duration=5 method='write' c=100 len=1048576 type='utf' benchmarker='wrk' -0.12 % ±0.36% ±0.47% ±0.62%
http/end-vs-write-end.js duration=5 method='write' c=100 len=131072 type='asc' benchmarker='wrk' 0.07 % ±0.76% ±1.01% ±1.32%
http/end-vs-write-end.js duration=5 method='write' c=100 len=131072 type='buf' benchmarker='wrk' -0.25 % ±0.51% ±0.68% ±0.89%
http/end-vs-write-end.js duration=5 method='write' c=100 len=131072 type='utf' benchmarker='wrk' 0.53 % ±1.00% ±1.34% ±1.74%
http/end-vs-write-end.js duration=5 method='write' c=100 len=262144 type='asc' benchmarker='wrk' -0.26 % ±0.61% ±0.81% ±1.06%
http/end-vs-write-end.js duration=5 method='write' c=100 len=262144 type='buf' benchmarker='wrk' -0.05 % ±0.47% ±0.62% ±0.81%
http/end-vs-write-end.js duration=5 method='write' c=100 len=262144 type='utf' benchmarker='wrk' -0.08 % ±0.56% ±0.74% ±0.96%
http/end-vs-write-end.js duration=5 method='write' c=100 len=65536 type='asc' benchmarker='wrk' -0.50 % ±0.96% ±1.28% ±1.66%
http/end-vs-write-end.js duration=5 method='write' c=100 len=65536 type='buf' benchmarker='wrk' -0.22 % ±0.71% ±0.94% ±1.23%
http/end-vs-write-end.js duration=5 method='write' c=100 len=65536 type='utf' benchmarker='wrk' 0.10 % ±0.58% ±0.77% ±1.01%
http/headers.js group='fewHeaders' duration=5 len=1 n=10 benchmarker='wrk' -0.23 % ±0.65% ±0.86% ±1.13%
http/headers.js group='fewHeaders' duration=5 len=5 n=10 benchmarker='wrk' 0.25 % ±0.59% ±0.79% ±1.03%
http/headers.js group='manyHeaders' duration=5 len=1 n=600 benchmarker='wrk' -0.11 % ±0.86% ±1.15% ±1.49%
http/headers.js group='manyHeaders' duration=5 len=100 n=600 benchmarker='wrk' 0.22 % ±1.12% ±1.49% ±1.94%
http/headers.js group='mediumHeaders' duration=5 len=1 n=50 benchmarker='wrk' -0.28 % ±0.51% ±0.67% ±0.88%
http/headers.js group='mediumHeaders' duration=5 len=10 n=50 benchmarker='wrk' 0.04 % ±0.53% ±0.71% ±0.93%
http/http_server_for_chunky_client.js type='send' n=2000 len=1 0.19 % ±0.57% ±0.77% ±1.00%
http/http_server_for_chunky_client.js type='send' n=2000 len=128 -0.12 % ±0.59% ±0.78% ±1.02%
http/http_server_for_chunky_client.js type='send' n=2000 len=16 -0.01 % ±0.60% ±0.79% ±1.03%
http/http_server_for_chunky_client.js type='send' n=2000 len=32 0.15 % ±0.61% ±0.81% ±1.06%
http/http_server_for_chunky_client.js type='send' n=2000 len=4 0.67 % ±0.69% ±0.92% ±1.21%
http/http_server_for_chunky_client.js type='send' n=2000 len=64 -0.30 % ±0.48% ±0.64% ±0.83%
http/http_server_for_chunky_client.js type='send' n=2000 len=8 -0.50 % ±0.55% ±0.73% ±0.95%
http/http_server_for_chunky_client.js type='send' n=5 len=1 -1.39 % ±2.60% ±3.47% ±4.51%
http/http_server_for_chunky_client.js type='send' n=5 len=128 -4.15 % ±13.02% ±17.32% ±22.54%
http/http_server_for_chunky_client.js type='send' n=5 len=16 7.54 % ±10.05% ±13.50% ±17.81%
http/http_server_for_chunky_client.js type='send' n=5 len=32 0.87 % ±11.95% ±15.91% ±20.71%
http/http_server_for_chunky_client.js type='send' n=5 len=4 1.73 % ±10.57% ±14.06% ±18.30%
http/http_server_for_chunky_client.js type='send' n=5 len=64 -5.12 % ±14.17% ±18.86% ±24.56%
http/http_server_for_chunky_client.js type='send' n=5 len=8 -2.55 % ±5.92% ±7.90% ±10.32%
http/http_server_for_chunky_client.js type='send' n=50 len=1 1.27 % ±2.86% ±3.81% ±4.96%
http/http_server_for_chunky_client.js type='send' n=50 len=128 * 5.17 % ±4.13% ±5.49% ±7.15%
http/http_server_for_chunky_client.js type='send' n=50 len=16 -0.71 % ±2.69% ±3.58% ±4.67%
http/http_server_for_chunky_client.js type='send' n=50 len=32 -0.12 % ±2.72% ±3.63% ±4.74%
http/http_server_for_chunky_client.js type='send' n=50 len=4 -1.47 % ±3.06% ±4.07% ±5.29%
http/http_server_for_chunky_client.js type='send' n=50 len=64 2.04 % ±3.51% ±4.67% ±6.09%
http/http_server_for_chunky_client.js type='send' n=50 len=8 -0.08 % ±2.21% ±2.94% ±3.84%
http/http_server_for_chunky_client.js type='send' n=500 len=1 -0.08 % ±0.80% ±1.07% ±1.40%
http/http_server_for_chunky_client.js type='send' n=500 len=128 -0.38 % ±0.70% ±0.93% ±1.21%
http/http_server_for_chunky_client.js type='send' n=500 len=16 * -0.94 % ±0.83% ±1.11% ±1.45%
http/http_server_for_chunky_client.js type='send' n=500 len=32 -0.43 % ±0.83% ±1.11% ±1.45%
http/http_server_for_chunky_client.js type='send' n=500 len=4 -0.02 % ±0.71% ±0.95% ±1.24%
http/http_server_for_chunky_client.js type='send' n=500 len=64 -0.19 % ±0.93% ±1.24% ±1.62%
http/http_server_for_chunky_client.js type='send' n=500 len=8 -0.15 % ±0.71% ±0.95% ±1.23%
http/incoming_headers.js duration=5 w=0 headers=20 connections=50 benchmarker='wrk' 0.04 % ±0.81% ±1.08% ±1.42%
http/incoming_headers.js duration=5 w=6 headers=20 connections=50 benchmarker='wrk' 0.04 % ±0.64% ±0.85% ±1.11%
http/set_header.js n=1000000 value='Connection' ** -2.20 % ±1.65% ±2.19% ±2.85%
http/set_header.js n=1000000 value='Content-Length' 0.29 % ±1.71% ±2.28% ±2.97%
http/set_header.js n=1000000 value='Content-Type' 1.33 % ±1.88% ±2.51% ±3.27%
http/set_header.js n=1000000 value='Set-Cookie' 1.14 % ±1.33% ±1.77% ±2.30%
http/set_header.js n=1000000 value='Transfer-Encoding' 1.06 % ±1.33% ±1.76% ±2.30%
http/set_header.js n=1000000 value='Vary' -0.57 % ±1.72% ±2.29% ±2.99%
http/set_header.js n=1000000 value='X-Powered-By' * 1.49 % ±1.33% ±1.77% ±2.30%
http/set-header.js duration=5 res='normal' benchmarker='wrk' *** 9.74 % ±0.78% ±1.04% ±1.35%
http/set-header.js duration=5 res='setHeader' benchmarker='wrk' *** 9.87 % ±0.83% ±1.10% ±1.44%
http/set-header.js duration=5 res='setHeaderWH' benchmarker='wrk' *** 9.59 % ±0.92% ±1.22% ±1.59%
http/simple.js duration=5 chunkedEnc=0 c=50 chunks=1 len=1024 type='buffer' benchmarker='wrk' *** 2.60 % ±0.75% ±1.00% ±1.30%
http/simple.js duration=5 chunkedEnc=0 c=50 chunks=1 len=1024 type='bytes' benchmarker='wrk' *** 9.54 % ±0.74% ±0.99% ±1.28%
http/simple.js duration=5 chunkedEnc=0 c=50 chunks=1 len=102400 type='buffer' benchmarker='wrk' ** 1.23 % ±0.75% ±0.99% ±1.29%
http/simple.js duration=5 chunkedEnc=0 c=50 chunks=1 len=102400 type='bytes' benchmarker='wrk' *** 1.98 % ±0.49% ±0.65% ±0.84%
http/simple.js duration=5 chunkedEnc=0 c=50 chunks=1 len=4 type='buffer' benchmarker='wrk' *** 2.43 % ±0.76% ±1.01% ±1.31%
http/simple.js duration=5 chunkedEnc=0 c=50 chunks=1 len=4 type='bytes' benchmarker='wrk' *** 9.55 % ±0.71% ±0.95% ±1.24%
http/simple.js duration=5 chunkedEnc=0 c=50 chunks=4 len=1024 type='buffer' benchmarker='wrk' *** 3.14 % ±0.86% ±1.15% ±1.50%
http/simple.js duration=5 chunkedEnc=0 c=50 chunks=4 len=1024 type='bytes' benchmarker='wrk' *** 2.94 % ±0.78% ±1.04% ±1.35%
http/simple.js duration=5 chunkedEnc=0 c=50 chunks=4 len=102400 type='buffer' benchmarker='wrk' *** 1.55 % ±0.62% ±0.82% ±1.07%
http/simple.js duration=5 chunkedEnc=0 c=50 chunks=4 len=102400 type='bytes' benchmarker='wrk' ** 1.10 % ±0.82% ±1.09% ±1.42%
http/simple.js duration=5 chunkedEnc=0 c=50 chunks=4 len=4 type='buffer' benchmarker='wrk' *** 3.91 % ±0.83% ±1.10% ±1.44%
http/simple.js duration=5 chunkedEnc=0 c=50 chunks=4 len=4 type='bytes' benchmarker='wrk' *** 3.47 % ±0.93% ±1.23% ±1.60%
http/simple.js duration=5 chunkedEnc=0 c=500 chunks=1 len=1024 type='buffer' benchmarker='wrk' *** 3.60 % ±0.96% ±1.27% ±1.66%
http/simple.js duration=5 chunkedEnc=0 c=500 chunks=1 len=1024 type='bytes' benchmarker='wrk' *** 9.20 % ±0.99% ±1.32% ±1.72%
http/simple.js duration=5 chunkedEnc=0 c=500 chunks=1 len=102400 type='buffer' benchmarker='wrk' *** 1.28 % ±0.53% ±0.71% ±0.93%
http/simple.js duration=5 chunkedEnc=0 c=500 chunks=1 len=102400 type='bytes' benchmarker='wrk' *** 1.28 % ±0.65% ±0.87% ±1.13%
http/simple.js duration=5 chunkedEnc=0 c=500 chunks=1 len=4 type='buffer' benchmarker='wrk' *** 3.59 % ±0.96% ±1.28% ±1.67%
http/simple.js duration=5 chunkedEnc=0 c=500 chunks=1 len=4 type='bytes' benchmarker='wrk' *** 9.93 % ±1.01% ±1.35% ±1.76%
http/simple.js duration=5 chunkedEnc=0 c=500 chunks=4 len=1024 type='buffer' benchmarker='wrk' *** 2.04 % ±0.98% ±1.31% ±1.70%
http/simple.js duration=5 chunkedEnc=0 c=500 chunks=4 len=1024 type='bytes' benchmarker='wrk' *** 2.14 % ±0.82% ±1.08% ±1.41%
http/simple.js duration=5 chunkedEnc=0 c=500 chunks=4 len=102400 type='buffer' benchmarker='wrk' *** 1.74 % ±0.67% ±0.89% ±1.16%
http/simple.js duration=5 chunkedEnc=0 c=500 chunks=4 len=102400 type='bytes' benchmarker='wrk' ** 1.10 % ±0.79% ±1.05% ±1.36%
http/simple.js duration=5 chunkedEnc=0 c=500 chunks=4 len=4 type='buffer' benchmarker='wrk' *** 3.20 % ±0.94% ±1.24% ±1.62%
http/simple.js duration=5 chunkedEnc=0 c=500 chunks=4 len=4 type='bytes' benchmarker='wrk' *** 3.12 % ±0.76% ±1.01% ±1.32%
http/simple.js duration=5 chunkedEnc=1 c=50 chunks=1 len=1024 type='buffer' benchmarker='wrk' -0.19 % ±0.80% ±1.06% ±1.38%
http/simple.js duration=5 chunkedEnc=1 c=50 chunks=1 len=1024 type='bytes' benchmarker='wrk' -0.44 % ±0.95% ±1.26% ±1.65%
http/simple.js duration=5 chunkedEnc=1 c=50 chunks=1 len=102400 type='buffer' benchmarker='wrk' 0.11 % ±0.61% ±0.81% ±1.06%
http/simple.js duration=5 chunkedEnc=1 c=50 chunks=1 len=102400 type='bytes' benchmarker='wrk' * -1.19 % ±1.11% ±1.47% ±1.92%
http/simple.js duration=5 chunkedEnc=1 c=50 chunks=1 len=4 type='buffer' benchmarker='wrk' -0.23 % ±0.80% ±1.07% ±1.39%
http/simple.js duration=5 chunkedEnc=1 c=50 chunks=1 len=4 type='bytes' benchmarker='wrk' 0.10 % ±0.75% ±1.00% ±1.30%
http/simple.js duration=5 chunkedEnc=1 c=50 chunks=4 len=1024 type='buffer' benchmarker='wrk' -0.55 % ±0.76% ±1.01% ±1.32%
http/simple.js duration=5 chunkedEnc=1 c=50 chunks=4 len=1024 type='bytes' benchmarker='wrk' 0.19 % ±0.95% ±1.27% ±1.65%
http/simple.js duration=5 chunkedEnc=1 c=50 chunks=4 len=102400 type='buffer' benchmarker='wrk' ** -1.32 % ±0.79% ±1.06% ±1.37%
http/simple.js duration=5 chunkedEnc=1 c=50 chunks=4 len=102400 type='bytes' benchmarker='wrk' 0.69 % ±1.07% ±1.42% ±1.85%
http/simple.js duration=5 chunkedEnc=1 c=50 chunks=4 len=4 type='buffer' benchmarker='wrk' 0.54 % ±0.81% ±1.07% ±1.40%
http/simple.js duration=5 chunkedEnc=1 c=50 chunks=4 len=4 type='bytes' benchmarker='wrk' 0.56 % ±0.71% ±0.95% ±1.23%
http/simple.js duration=5 chunkedEnc=1 c=500 chunks=1 len=1024 type='buffer' benchmarker='wrk' -0.48 % ±0.80% ±1.07% ±1.39%
http/simple.js duration=5 chunkedEnc=1 c=500 chunks=1 len=1024 type='bytes' benchmarker='wrk' -0.62 % ±0.85% ±1.13% ±1.48%
http/simple.js duration=5 chunkedEnc=1 c=500 chunks=1 len=102400 type='buffer' benchmarker='wrk' -0.20 % ±0.69% ±0.92% ±1.20%
http/simple.js duration=5 chunkedEnc=1 c=500 chunks=1 len=102400 type='bytes' benchmarker='wrk' 0.43 % ±1.18% ±1.56% ±2.04%
http/simple.js duration=5 chunkedEnc=1 c=500 chunks=1 len=4 type='buffer' benchmarker='wrk' 0.29 % ±0.89% ±1.19% ±1.55%
http/simple.js duration=5 chunkedEnc=1 c=500 chunks=1 len=4 type='bytes' benchmarker='wrk' * -1.01 % ±0.80% ±1.07% ±1.39%
http/simple.js duration=5 chunkedEnc=1 c=500 chunks=4 len=1024 type='buffer' benchmarker='wrk' -0.18 % ±0.68% ±0.90% ±1.18%
http/simple.js duration=5 chunkedEnc=1 c=500 chunks=4 len=1024 type='bytes' benchmarker='wrk' 0.09 % ±0.65% ±0.86% ±1.12%
http/simple.js duration=5 chunkedEnc=1 c=500 chunks=4 len=102400 type='buffer' benchmarker='wrk' * -0.55 % ±0.49% ±0.66% ±0.86%
http/simple.js duration=5 chunkedEnc=1 c=500 chunks=4 len=102400 type='bytes' benchmarker='wrk' 0.10 % ±0.82% ±1.09% ±1.42%
http/simple.js duration=5 chunkedEnc=1 c=500 chunks=4 len=4 type='buffer' benchmarker='wrk' 0.35 % ±0.74% ±0.98% ±1.28%
http/simple.js duration=5 chunkedEnc=1 c=500 chunks=4 len=4 type='bytes' benchmarker='wrk' -0.26 % ±0.65% ±0.86% ±1.12%
http/upgrade.js n=1000 0.73 % ±2.37% ±3.16% ±4.11%
http/upgrade.js n=5 6.72 % ±8.30% ±11.05% ±14.38%

Be aware that when doing many comparisons the risk of a false-positive result increases.

In this case, there are 235 comparisons, you can thus expect the following amount of false-positive results:

11.75 false positives, when considering a 5% risk acceptance (*, **, *),

2.35 false positives, when considering a 1% risk acceptance (, ),

0.24 false positives, when considering a 0.1% risk acceptance ()
Looks good I think. Headlines:
  • No notable regressions - each of the small negative cases I can see are low-confidence and fit into an overall pattern of no change considering the tests around them
  • A very consistent 9.59% - 9.87% speed up in http/set-header.js test, which tests headers + res.end(body).
  • For http/simple:

    • Consistent boost around 9.5% with type=bytes, no chunking, and len up to 1024.
    • 3% boost with type=buffer, on the same small non-chunked responses.
    • Both buffer & byte body perf dropping to about 1-2% improvement for larger bodies (1MB).
    • No significant change with chunked encoding.
  • 10.48% boost to http/end-string test with 1KB, dropping to 5.59% with 16KB, down to 2.47% improvement with 1MB.
  • ~2% boost across various http/end-vs-write-end.js cases that call end(data) on different large sizes.
Looks pretty convincing to me! All approved and ready-to-go now and I think this is all just good news, so I'll commit-queue.
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aduh95 pushed a commit
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@pimterry@aduh95
http: improve performance with known-length calls to end()
89ac179
This boosts RPS performance for the common API case where you call
`res.end(data)` with the entire response by up to 9%.
Signed-off-by: Tim Perry <pimterry@gmail.com>
PR-URL: #65466
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
Reviewed-By: Yagiz Nizipli <yagiz@nizipli.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Gürgün Dayıoğlu <hey@gurgun.day>
aduh95 pushed a commit
that referenced
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Aug 25, 2026
@pimterry@aduh95
http: improve performance with known-length calls to end()
c2c31d6
This boosts RPS performance for the common API case where you call
`res.end(data)` with the entire response by up to 9%.
Signed-off-by: Tim Perry <pimterry@gmail.com>
PR-URL: #65466
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
Reviewed-By: Yagiz Nizipli <yagiz@nizipli.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Gürgün Dayıoğlu <hey@gurgun.day>
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@pimterry@aduh95
http: improve performance with known-length calls to end()
5b13d30
This boosts RPS performance for the common API case where you call
`res.end(data)` with the entire response by up to 9%.
Signed-off-by: Tim Perry <pimterry@gmail.com>
PR-URL: #65466
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
Reviewed-By: Yagiz Nizipli <yagiz@nizipli.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Gürgün Dayıoğlu <hey@gurgun.day>
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if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Auto-enable theater mode on YouTube\n(function() {\n function tryTheater() {\n var btn = document.querySelector('button[aria-label=\"Theater mode\"], ytd-player #player button[title=\"Theater mode\"]');\n if (btn && !btn.classList.contains('activated')) {\n btn.click();\n }\n }\n \n // Try immediately\n tryTheater();\n \n // Try after navigation (SPA)\n var lastUrl = location.href;\n setInterval(function() {\n if (location.href !== lastUrl) {\n lastUrl = location.href;\n setTimeout(tryTheater, 500);\n }\n }, 1000);\n \n // Also try on player load\n var observer = new MutationObserver(tryTheater);\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "YouTube Theater Mode Default");
}
} catch(__e) { console.warn('[Userscript:YouTube Theater Mode Default]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

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http: improve performance for end() with known-length string - #65466
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http: improve performance for end() with known-length string#65466
nodejs-github-bot merged 1 commit into
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pimterry:h1-clean-end-perf
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When you call end(data) on an outgoing HTTP request, we previously wrote the data, and then ran _send('', ...) just to trigger flushing the headers, which resulted in an extra zero-byte write call and bonus nextTick before 'finish'.
When the length is known and content-length is used (not chunking, so we don't need a terminator) we can skip this completely: prep the content-length header explicitly, and combine the finish into the existing write step.
This drops a nextTick, and goes from 2 write calls to 1 for the very common case of response.end(data) with a string, and for buffer data goes from 3 writes to 2.
In practice, in the tiny benchmark here which I think represents a very common use case (small API responses) I see this boosting HTTP RPS by up to 9% for writes up to 1KB or so. For larger responses the response write time starts to outweigh this, but I still see 3% RPS boost at 16KB. Needs autocannon to hit the rates required, you can test yourself with:
node benchmark/compare.js --old ./node-main --new ./node-pr --runs 20 --set benchmarker=autocannon --filter end-string http
Added a new test confirming the specific details and edge cases this touches, and updated one existing test which specifically asserted that end(data) triggered two writes, including the empty one.
@pimterry
http: improve performance with known-length calls to end()
659d6b9
This boosts RPS performance for the common API case where you call
`res.end(data)` with the entire response by up to 9%.
Signed-off-by: Tim Perry <pimterry@gmail.com>
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Codecov Report
✅ All modified and coverable lines are covered by tests.

✅ Project coverage is 90.13%. Comparing base (15940ef) to head (659d6b9).
⚠️ Report is 61 commits behind head on main.
Additional details and impacted files
@@ Coverage Diff @@## main #65466 +/- ##
==========================================
- Coverage 90.14% 90.13% -0.01% 
==========================================
Files 751 751 Lines 252298 252333 +35 Branches 47446 47449 +3 ==========================================
+ Hits 227436 227451 +15 - Misses 16175 16186 +11 - Partials 8687 8696 +9 
Files with missing linesCoverage Δ
lib/_http_outgoing.js97.76% <100.00%> (-0.02%)⬇️
... and 34 files with indirect coverage changes
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CI: https://ci.nodejs.org/job/node-test-pull-request/76211/
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@bjohansebas benchmark label was a good suggestion. I've done a run here.
Unfortunately it seems like the microbenchmark job is broken generally (cc @nodejs/build) and all recent jobs have failed with:
++ Rscript benchmark/compare.R
Error: package or namespace load failed for ‘ggplot2’ in dyn.load(file, DLLpath = DLLpath, ...):
unable to load shared object '/usr/local/lib/R/site-library/rlang/libs/rlang.so':
/usr/local/lib/R/site-library/rlang/libs/rlang.so: undefined symbol: SETLENGTH
Execution halted

I've manually extracted the CSV from the console output to get some numbers though, and run node-benchmark-compare on the result, which gives:
Details
 confidence improvement accuracy (*) (**) (***)
http/bench-parser-fragmented.js n=100000 frags=2 len=16 -0.20 % ±1.06% ±1.42% ±1.85%
http/bench-parser-fragmented.js n=100000 frags=2 len=8 -0.01 % ±0.94% ±1.25% ±1.63%
http/bench-parser-fragmented.js n=100000 frags=4 len=16 -0.17 % ±0.77% ±1.02% ±1.33%
http/bench-parser-fragmented.js n=100000 frags=4 len=8 -0.57 % ±0.64% ±0.85% ±1.11%
http/bench-parser-fragmented.js n=100000 frags=8 len=16 -0.07 % ±0.84% ±1.12% ±1.45%
http/bench-parser-fragmented.js n=100000 frags=8 len=8 0.43 % ±0.78% ±1.04% ±1.35%
http/bench-parser.js n=100000 len=16 0.20 % ±0.93% ±1.24% ±1.61%
http/bench-parser.js n=100000 len=32 0.03 % ±0.68% ±0.90% ±1.17%
http/bench-parser.js n=100000 len=4 0.60 % ±1.08% ±1.43% ±1.86%
http/bench-parser.js n=100000 len=8 0.32 % ±1.11% ±1.47% ±1.92%
http/check_invalid_header_char.js n=1000000 input='' 1.25 % ±2.48% ±3.30% ±4.30%
http/check_invalid_header_char.js n=1000000 input='\t\t\t\t\t\t\t\t\t\tFoo bar baz' 0.39 % ±1.66% ±2.21% ±2.88%
http/check_invalid_header_char.js n=1000000 input='\x7F' * 4.92 % ±3.90% ±5.19% ±6.75%
http/check_invalid_header_char.js n=1000000 input='1' -0.41 % ±3.47% ±4.62% ±6.02%
http/check_invalid_header_char.js n=1000000 input='20091' -0.50 % ±3.85% ±5.12% ±6.66%
http/check_invalid_header_char.js n=1000000 input='close' 0.49 % ±3.34% ±4.44% ±5.78%
http/check_invalid_header_char.js n=1000000 input='en-US' -0.66 % ±3.59% ±4.77% ±6.21%
http/check_invalid_header_char.js n=1000000 input='foo\nbar' -1.88 % ±2.70% ±3.60% ±4.70%
http/check_invalid_header_char.js n=1000000 input='group_acmeair' 0.85 % ±1.82% ±2.42% ±3.16%
http/check_invalid_header_char.js n=1000000 input='gzip' -0.60 % ±3.29% ±4.37% ±5.70%
http/check_invalid_header_char.js n=1000000 input='keep-alive' -1.28 % ±2.16% ±2.88% ±3.75%
http/check_invalid_header_char.js n=1000000 input='LONG_AND_INVALID' 0.08 % ±1.13% ±1.51% ±1.97%
http/check_invalid_header_char.js n=1000000 input='private' 1.00 % ±2.68% ±3.57% ±4.65%
http/check_invalid_header_char.js n=1000000 input='SAMEORIGIN' 1.36 % ±2.81% ±3.74% ±4.88%
http/check_invalid_header_char.js n=1000000 input='Sat, 07 May 2016 16:54:48 GMT' 0.79 % ±1.41% ±1.87% ±2.44%
http/check_invalid_header_char.js n=1000000 input='text/html; charset=utf-8' -0.12 % ±1.41% ±1.88% ±2.45%
http/check_invalid_header_char.js n=1000000 input='text/plain' -1.49 % ±2.96% ±3.95% ±5.14%
http/check_invalid_header_char.js n=1000000 input='中文呢' 1.95 % ±2.71% ±3.61% ±4.69%
http/check_is_http_token.js n=1000000 key=':' -0.22 % ±2.22% ±2.96% ±3.85%
http/check_is_http_token.js n=1000000 key=':alternate-protocol' 2.82 % ±4.07% ±5.42% ±7.06%
http/check_is_http_token.js n=1000000 key='((((())))' -1.22 % ±2.75% ±3.71% ±4.91%
http/check_is_http_token.js n=1000000 key='@@' 0.52 % ±2.14% ±2.85% ±3.71%
http/check_is_http_token.js n=1000000 key='Accept-Ranges' 0.51 % ±2.25% ±2.99% ±3.90%
http/check_is_http_token.js n=1000000 key='alt-svc' -0.09 % ±2.23% ±2.97% ±3.87%
http/check_is_http_token.js n=1000000 key='alternate-protocol:' -0.94 % ±2.08% ±2.77% ±3.61%
http/check_is_http_token.js n=1000000 key='alternate-protocol' -1.19 % ±2.32% ±3.09% ±4.03%
http/check_is_http_token.js n=1000000 key='Cache-Control' -0.96 % ±2.14% ±2.85% ±3.71%
http/check_is_http_token.js n=1000000 key='Connection' 0.78 % ±2.39% ±3.19% ±4.15%
http/check_is_http_token.js n=1000000 key='Content-Encoding' * -2.76 % ±2.26% ±3.01% ±3.92%
http/check_is_http_token.js n=1000000 key='content-length' 0.93 % ±2.27% ±3.02% ±3.92%
http/check_is_http_token.js n=1000000 key='Content-Location' -0.15 % ±2.52% ±3.35% ±4.36%
http/check_is_http_token.js n=1000000 key='content-type' -0.49 % ±2.55% ±3.39% ±4.41%
http/check_is_http_token.js n=1000000 key='Content-Type' 0.46 % ±2.58% ±3.43% ±4.47%
http/check_is_http_token.js n=1000000 key='date' 0.62 % ±2.42% ±3.22% ±4.19%
http/check_is_http_token.js n=1000000 key='ETag' -2.60 % ±3.97% ±5.32% ±7.01%
http/check_is_http_token.js n=1000000 key='Expires' ** 3.69 % ±2.64% ±3.52% ±4.59%
http/check_is_http_token.js n=1000000 key='Keep-Alive' -0.03 % ±2.59% ±3.45% ±4.48%
http/check_is_http_token.js n=1000000 key='Last-Modified' -0.99 % ±2.34% ±3.12% ±4.07%
http/check_is_http_token.js n=1000000 key='location' 0.79 % ±2.44% ±3.25% ±4.23%
http/check_is_http_token.js n=1000000 key='server' 0.37 % ±2.46% ±3.27% ±4.25%
http/check_is_http_token.js n=1000000 key='Server' * 3.70 % ±3.00% ±4.00% ±5.23%
http/check_is_http_token.js n=1000000 key='status' ** -4.32 % ±3.09% ±4.13% ±5.40%
http/check_is_http_token.js n=1000000 key='TCN' -0.86 % ±1.00% ±1.33% ±1.73%
http/check_is_http_token.js n=1000000 key='Transfer-Encoding' -1.00 % ±2.32% ±3.09% ±4.02%
http/check_is_http_token.js n=1000000 key='Vary' -0.56 % ±1.47% ±1.95% ±2.54%
http/check_is_http_token.js n=1000000 key='version' 1.90 % ±2.74% ±3.65% ±4.75%
http/check_is_http_token.js n=1000000 key='x-frame-options' 0.57 % ±2.05% ±2.73% ±3.55%
http/check_is_http_token.js n=1000000 key='x-xss-protection' -1.39 % ±2.29% ±3.06% ±3.99%
http/check_is_http_token.js n=1000000 key='中文呢' -1.00 % ±4.47% ±6.01% ±7.92%
http/chunked.js duration=5 c=100 len=1 n=1 benchmarker='wrk' -0.19 % ±0.68% ±0.91% ±1.18%
http/chunked.js duration=5 c=100 len=1 n=16 benchmarker='wrk' 0.41 % ±0.78% ±1.03% ±1.35%
http/chunked.js duration=5 c=100 len=1 n=4 benchmarker='wrk' 0.61 % ±2.08% ±2.76% ±3.60%
http/chunked.js duration=5 c=100 len=1 n=8 benchmarker='wrk' 0.13 % ±0.81% ±1.07% ±1.40%
http/chunked.js duration=5 c=100 len=256 n=1 benchmarker='wrk' -0.10 % ±0.70% ±0.93% ±1.21%
http/chunked.js duration=5 c=100 len=256 n=16 benchmarker='wrk' -0.70 % ±0.73% ±0.97% ±1.26%
http/chunked.js duration=5 c=100 len=256 n=4 benchmarker='wrk' -0.58 % ±1.84% ±2.45% ±3.18%
http/chunked.js duration=5 c=100 len=256 n=8 benchmarker='wrk' 0.11 % ±0.87% ±1.16% ±1.51%
http/chunked.js duration=5 c=100 len=64 n=1 benchmarker='wrk' -0.26 % ±0.60% ±0.80% ±1.04%
http/chunked.js duration=5 c=100 len=64 n=16 benchmarker='wrk' 0.56 % ±0.63% ±0.84% ±1.10%
http/chunked.js duration=5 c=100 len=64 n=4 benchmarker='wrk' 0.08 % ±1.81% ±2.41% ±3.15%
http/chunked.js duration=5 c=100 len=64 n=8 benchmarker='wrk' 0.26 % ±0.75% ±1.00% ±1.30%
http/client-request-body.js method='end' len=1024 type='asc' dur=5 -0.06 % ±0.69% ±0.92% ±1.20%
http/client-request-body.js method='end' len=1024 type='buf' dur=5 0.01 % ±0.76% ±1.02% ±1.32%
http/client-request-body.js method='end' len=1024 type='utf' dur=5 -0.28 % ±0.59% ±0.79% ±1.03%
http/client-request-body.js method='end' len=256 type='asc' dur=5 -0.49 % ±0.67% ±0.90% ±1.17%
http/client-request-body.js method='end' len=256 type='buf' dur=5 * -0.75 % ±0.68% ±0.90% ±1.18%
http/client-request-body.js method='end' len=256 type='utf' dur=5 0.03 % ±0.62% ±0.83% ±1.08%
http/client-request-body.js method='end' len=32 type='asc' dur=5 -0.01 % ±0.56% ±0.75% ±0.98%
http/client-request-body.js method='end' len=32 type='buf' dur=5 -0.37 % ±0.60% ±0.79% ±1.03%
http/client-request-body.js method='end' len=32 type='utf' dur=5 -0.16 % ±0.62% ±0.83% ±1.08%
http/client-request-body.js method='write' len=1024 type='asc' dur=5 -0.16 % ±0.78% ±1.03% ±1.34%
http/client-request-body.js method='write' len=1024 type='buf' dur=5 -0.34 % ±0.68% ±0.90% ±1.17%
http/client-request-body.js method='write' len=1024 type='utf' dur=5 0.06 % ±0.78% ±1.04% ±1.35%
http/client-request-body.js method='write' len=256 type='asc' dur=5 0.27 % ±0.70% ±0.93% ±1.21%
http/client-request-body.js method='write' len=256 type='buf' dur=5 0.09 % ±0.76% ±1.02% ±1.32%
http/client-request-body.js method='write' len=256 type='utf' dur=5 0.49 % ±0.59% ±0.79% ±1.03%
http/client-request-body.js method='write' len=32 type='asc' dur=5 -0.40 % ±0.64% ±0.86% ±1.11%
http/client-request-body.js method='write' len=32 type='buf' dur=5 -0.21 % ±0.65% ±0.86% ±1.12%
http/client-request-body.js method='write' len=32 type='utf' dur=5 0.02 % ±0.60% ±0.79% ±1.03%
http/cluster.js duration=5 c=50 len=1024 type='buffer' benchmarker='wrk' 0.13 % ±0.46% ±0.62% ±0.81%
http/cluster.js duration=5 c=50 len=1024 type='bytes' benchmarker='wrk' -0.11 % ±0.38% ±0.50% ±0.66%
http/cluster.js duration=5 c=50 len=102400 type='buffer' benchmarker='wrk' -0.24 % ±0.49% ±0.65% ±0.85%
http/cluster.js duration=5 c=50 len=102400 type='bytes' benchmarker='wrk' 0.14 % ±0.80% ±1.06% ±1.38%
http/cluster.js duration=5 c=50 len=4 type='buffer' benchmarker='wrk' -0.23 % ±0.29% ±0.39% ±0.51%
http/cluster.js duration=5 c=50 len=4 type='bytes' benchmarker='wrk' 0.00 % ±0.51% ±0.67% ±0.88%
http/cluster.js duration=5 c=500 len=1024 type='buffer' benchmarker='wrk' ** -0.77 % ±0.50% ±0.67% ±0.87%
http/cluster.js duration=5 c=500 len=1024 type='bytes' benchmarker='wrk' -0.18 % ±0.65% ±0.86% ±1.12%
http/cluster.js duration=5 c=500 len=102400 type='buffer' benchmarker='wrk' -0.18 % ±0.59% ±0.78% ±1.02%
http/cluster.js duration=5 c=500 len=102400 type='bytes' benchmarker='wrk' 0.28 % ±0.72% ±0.95% ±1.24%
http/cluster.js duration=5 c=500 len=4 type='buffer' benchmarker='wrk' -0.25 % ±0.47% ±0.62% ±0.81%
http/cluster.js duration=5 c=500 len=4 type='bytes' benchmarker='wrk' -0.36 % ±0.52% ±0.70% ±0.91%
http/create-clientrequest.js e=1 arg='options' url='idn' 2.09 % ±7.80% ±10.38% ±13.50%
http/create-clientrequest.js e=1 arg='options' url='long' -9.98 % ±14.10% ±18.77% ±24.46%
http/create-clientrequest.js e=1 arg='options' url='wpt' -4.69 % ±6.75% ±8.98% ±11.70%
http/create-clientrequest.js e=1 arg='string' url='idn' -4.15 % ±10.23% ±13.61% ±17.71%
http/create-clientrequest.js e=1 arg='string' url='long' -0.93 % ±12.77% ±16.99% ±22.12%
http/create-clientrequest.js e=1 arg='string' url='wpt' 0.60 % ±11.36% ±15.12% ±19.68%
http/create-clientrequest.js e=1 arg='URL' url='idn' 0.87 % ±9.17% ±12.20% ±15.88%
http/create-clientrequest.js e=1 arg='URL' url='long' -5.01 % ±10.02% ±13.35% ±17.41%
http/create-clientrequest.js e=1 arg='URL' url='wpt' 1.99 % ±8.00% ±10.64% ±13.85%
http/end-string.js duration=5 c=50 len=1024 benchmarker='wrk' *** 10.48 % ±0.81% ±1.08% ±1.41%
http/end-string.js duration=5 c=50 len=102400 benchmarker='wrk' *** 2.47 % ±0.50% ±0.66% ±0.86%
http/end-string.js duration=5 c=50 len=16384 benchmarker='wrk' *** 5.59 % ±0.89% ±1.19% ±1.55%
http/end-string.js duration=5 c=50 len=4 benchmarker='wrk' *** 9.92 % ±0.82% ±1.10% ±1.43%
http/end-string.js duration=5 c=50 len=64 benchmarker='wrk' *** 8.43 % ±0.71% ±0.94% ±1.23%
http/end-vs-write-end.js duration=5 method='end' c=100 len=1048576 type='asc' benchmarker='wrk' *** 2.48 % ±0.47% ±0.62% ±0.81%
http/end-vs-write-end.js duration=5 method='end' c=100 len=1048576 type='buf' benchmarker='wrk' -0.12 % ±0.43% ±0.57% ±0.74%
http/end-vs-write-end.js duration=5 method='end' c=100 len=1048576 type='utf' benchmarker='wrk' *** 0.68 % ±0.38% ±0.51% ±0.66%
http/end-vs-write-end.js duration=5 method='end' c=100 len=131072 type='asc' benchmarker='wrk' ** 1.19 % ±0.81% ±1.09% ±1.43%
http/end-vs-write-end.js duration=5 method='end' c=100 len=131072 type='buf' benchmarker='wrk' *** 1.50 % ±0.59% ±0.78% ±1.01%
http/end-vs-write-end.js duration=5 method='end' c=100 len=131072 type='utf' benchmarker='wrk' *** 2.25 % ±0.45% ±0.59% ±0.77%
http/end-vs-write-end.js duration=5 method='end' c=100 len=262144 type='asc' benchmarker='wrk' *** 1.18 % ±0.42% ±0.56% ±0.73%
http/end-vs-write-end.js duration=5 method='end' c=100 len=262144 type='buf' benchmarker='wrk' *** 0.92 % ±0.48% ±0.63% ±0.83%
http/end-vs-write-end.js duration=5 method='end' c=100 len=262144 type='utf' benchmarker='wrk' *** 1.25 % ±0.32% ±0.43% ±0.56%
http/end-vs-write-end.js duration=5 method='end' c=100 len=65536 type='asc' benchmarker='wrk' *** 1.60 % ±0.83% ±1.10% ±1.44%
http/end-vs-write-end.js duration=5 method='end' c=100 len=65536 type='buf' benchmarker='wrk' *** 2.34 % ±0.88% ±1.18% ±1.53%
http/end-vs-write-end.js duration=5 method='end' c=100 len=65536 type='utf' benchmarker='wrk' *** 2.95 % ±0.48% ±0.64% ±0.83%
http/end-vs-write-end.js duration=5 method='write' c=100 len=1048576 type='asc' benchmarker='wrk' -0.33 % ±0.57% ±0.77% ±1.00%
http/end-vs-write-end.js duration=5 method='write' c=100 len=1048576 type='buf' benchmarker='wrk' -0.16 % ±0.52% ±0.69% ±0.90%
http/end-vs-write-end.js duration=5 method='write' c=100 len=1048576 type='utf' benchmarker='wrk' -0.12 % ±0.36% ±0.47% ±0.62%
http/end-vs-write-end.js duration=5 method='write' c=100 len=131072 type='asc' benchmarker='wrk' 0.07 % ±0.76% ±1.01% ±1.32%
http/end-vs-write-end.js duration=5 method='write' c=100 len=131072 type='buf' benchmarker='wrk' -0.25 % ±0.51% ±0.68% ±0.89%
http/end-vs-write-end.js duration=5 method='write' c=100 len=131072 type='utf' benchmarker='wrk' 0.53 % ±1.00% ±1.34% ±1.74%
http/end-vs-write-end.js duration=5 method='write' c=100 len=262144 type='asc' benchmarker='wrk' -0.26 % ±0.61% ±0.81% ±1.06%
http/end-vs-write-end.js duration=5 method='write' c=100 len=262144 type='buf' benchmarker='wrk' -0.05 % ±0.47% ±0.62% ±0.81%
http/end-vs-write-end.js duration=5 method='write' c=100 len=262144 type='utf' benchmarker='wrk' -0.08 % ±0.56% ±0.74% ±0.96%
http/end-vs-write-end.js duration=5 method='write' c=100 len=65536 type='asc' benchmarker='wrk' -0.50 % ±0.96% ±1.28% ±1.66%
http/end-vs-write-end.js duration=5 method='write' c=100 len=65536 type='buf' benchmarker='wrk' -0.22 % ±0.71% ±0.94% ±1.23%
http/end-vs-write-end.js duration=5 method='write' c=100 len=65536 type='utf' benchmarker='wrk' 0.10 % ±0.58% ±0.77% ±1.01%
http/headers.js group='fewHeaders' duration=5 len=1 n=10 benchmarker='wrk' -0.23 % ±0.65% ±0.86% ±1.13%
http/headers.js group='fewHeaders' duration=5 len=5 n=10 benchmarker='wrk' 0.25 % ±0.59% ±0.79% ±1.03%
http/headers.js group='manyHeaders' duration=5 len=1 n=600 benchmarker='wrk' -0.11 % ±0.86% ±1.15% ±1.49%
http/headers.js group='manyHeaders' duration=5 len=100 n=600 benchmarker='wrk' 0.22 % ±1.12% ±1.49% ±1.94%
http/headers.js group='mediumHeaders' duration=5 len=1 n=50 benchmarker='wrk' -0.28 % ±0.51% ±0.67% ±0.88%
http/headers.js group='mediumHeaders' duration=5 len=10 n=50 benchmarker='wrk' 0.04 % ±0.53% ±0.71% ±0.93%
http/http_server_for_chunky_client.js type='send' n=2000 len=1 0.19 % ±0.57% ±0.77% ±1.00%
http/http_server_for_chunky_client.js type='send' n=2000 len=128 -0.12 % ±0.59% ±0.78% ±1.02%
http/http_server_for_chunky_client.js type='send' n=2000 len=16 -0.01 % ±0.60% ±0.79% ±1.03%
http/http_server_for_chunky_client.js type='send' n=2000 len=32 0.15 % ±0.61% ±0.81% ±1.06%
http/http_server_for_chunky_client.js type='send' n=2000 len=4 0.67 % ±0.69% ±0.92% ±1.21%
http/http_server_for_chunky_client.js type='send' n=2000 len=64 -0.30 % ±0.48% ±0.64% ±0.83%
http/http_server_for_chunky_client.js type='send' n=2000 len=8 -0.50 % ±0.55% ±0.73% ±0.95%
http/http_server_for_chunky_client.js type='send' n=5 len=1 -1.39 % ±2.60% ±3.47% ±4.51%
http/http_server_for_chunky_client.js type='send' n=5 len=128 -4.15 % ±13.02% ±17.32% ±22.54%
http/http_server_for_chunky_client.js type='send' n=5 len=16 7.54 % ±10.05% ±13.50% ±17.81%
http/http_server_for_chunky_client.js type='send' n=5 len=32 0.87 % ±11.95% ±15.91% ±20.71%
http/http_server_for_chunky_client.js type='send' n=5 len=4 1.73 % ±10.57% ±14.06% ±18.30%
http/http_server_for_chunky_client.js type='send' n=5 len=64 -5.12 % ±14.17% ±18.86% ±24.56%
http/http_server_for_chunky_client.js type='send' n=5 len=8 -2.55 % ±5.92% ±7.90% ±10.32%
http/http_server_for_chunky_client.js type='send' n=50 len=1 1.27 % ±2.86% ±3.81% ±4.96%
http/http_server_for_chunky_client.js type='send' n=50 len=128 * 5.17 % ±4.13% ±5.49% ±7.15%
http/http_server_for_chunky_client.js type='send' n=50 len=16 -0.71 % ±2.69% ±3.58% ±4.67%
http/http_server_for_chunky_client.js type='send' n=50 len=32 -0.12 % ±2.72% ±3.63% ±4.74%
http/http_server_for_chunky_client.js type='send' n=50 len=4 -1.47 % ±3.06% ±4.07% ±5.29%
http/http_server_for_chunky_client.js type='send' n=50 len=64 2.04 % ±3.51% ±4.67% ±6.09%
http/http_server_for_chunky_client.js type='send' n=50 len=8 -0.08 % ±2.21% ±2.94% ±3.84%
http/http_server_for_chunky_client.js type='send' n=500 len=1 -0.08 % ±0.80% ±1.07% ±1.40%
http/http_server_for_chunky_client.js type='send' n=500 len=128 -0.38 % ±0.70% ±0.93% ±1.21%
http/http_server_for_chunky_client.js type='send' n=500 len=16 * -0.94 % ±0.83% ±1.11% ±1.45%
http/http_server_for_chunky_client.js type='send' n=500 len=32 -0.43 % ±0.83% ±1.11% ±1.45%
http/http_server_for_chunky_client.js type='send' n=500 len=4 -0.02 % ±0.71% ±0.95% ±1.24%
http/http_server_for_chunky_client.js type='send' n=500 len=64 -0.19 % ±0.93% ±1.24% ±1.62%
http/http_server_for_chunky_client.js type='send' n=500 len=8 -0.15 % ±0.71% ±0.95% ±1.23%
http/incoming_headers.js duration=5 w=0 headers=20 connections=50 benchmarker='wrk' 0.04 % ±0.81% ±1.08% ±1.42%
http/incoming_headers.js duration=5 w=6 headers=20 connections=50 benchmarker='wrk' 0.04 % ±0.64% ±0.85% ±1.11%
http/set_header.js n=1000000 value='Connection' ** -2.20 % ±1.65% ±2.19% ±2.85%
http/set_header.js n=1000000 value='Content-Length' 0.29 % ±1.71% ±2.28% ±2.97%
http/set_header.js n=1000000 value='Content-Type' 1.33 % ±1.88% ±2.51% ±3.27%
http/set_header.js n=1000000 value='Set-Cookie' 1.14 % ±1.33% ±1.77% ±2.30%
http/set_header.js n=1000000 value='Transfer-Encoding' 1.06 % ±1.33% ±1.76% ±2.30%
http/set_header.js n=1000000 value='Vary' -0.57 % ±1.72% ±2.29% ±2.99%
http/set_header.js n=1000000 value='X-Powered-By' * 1.49 % ±1.33% ±1.77% ±2.30%
http/set-header.js duration=5 res='normal' benchmarker='wrk' *** 9.74 % ±0.78% ±1.04% ±1.35%
http/set-header.js duration=5 res='setHeader' benchmarker='wrk' *** 9.87 % ±0.83% ±1.10% ±1.44%
http/set-header.js duration=5 res='setHeaderWH' benchmarker='wrk' *** 9.59 % ±0.92% ±1.22% ±1.59%
http/simple.js duration=5 chunkedEnc=0 c=50 chunks=1 len=1024 type='buffer' benchmarker='wrk' *** 2.60 % ±0.75% ±1.00% ±1.30%
http/simple.js duration=5 chunkedEnc=0 c=50 chunks=1 len=1024 type='bytes' benchmarker='wrk' *** 9.54 % ±0.74% ±0.99% ±1.28%
http/simple.js duration=5 chunkedEnc=0 c=50 chunks=1 len=102400 type='buffer' benchmarker='wrk' ** 1.23 % ±0.75% ±0.99% ±1.29%
http/simple.js duration=5 chunkedEnc=0 c=50 chunks=1 len=102400 type='bytes' benchmarker='wrk' *** 1.98 % ±0.49% ±0.65% ±0.84%
http/simple.js duration=5 chunkedEnc=0 c=50 chunks=1 len=4 type='buffer' benchmarker='wrk' *** 2.43 % ±0.76% ±1.01% ±1.31%
http/simple.js duration=5 chunkedEnc=0 c=50 chunks=1 len=4 type='bytes' benchmarker='wrk' *** 9.55 % ±0.71% ±0.95% ±1.24%
http/simple.js duration=5 chunkedEnc=0 c=50 chunks=4 len=1024 type='buffer' benchmarker='wrk' *** 3.14 % ±0.86% ±1.15% ±1.50%
http/simple.js duration=5 chunkedEnc=0 c=50 chunks=4 len=1024 type='bytes' benchmarker='wrk' *** 2.94 % ±0.78% ±1.04% ±1.35%
http/simple.js duration=5 chunkedEnc=0 c=50 chunks=4 len=102400 type='buffer' benchmarker='wrk' *** 1.55 % ±0.62% ±0.82% ±1.07%
http/simple.js duration=5 chunkedEnc=0 c=50 chunks=4 len=102400 type='bytes' benchmarker='wrk' ** 1.10 % ±0.82% ±1.09% ±1.42%
http/simple.js duration=5 chunkedEnc=0 c=50 chunks=4 len=4 type='buffer' benchmarker='wrk' *** 3.91 % ±0.83% ±1.10% ±1.44%
http/simple.js duration=5 chunkedEnc=0 c=50 chunks=4 len=4 type='bytes' benchmarker='wrk' *** 3.47 % ±0.93% ±1.23% ±1.60%
http/simple.js duration=5 chunkedEnc=0 c=500 chunks=1 len=1024 type='buffer' benchmarker='wrk' *** 3.60 % ±0.96% ±1.27% ±1.66%
http/simple.js duration=5 chunkedEnc=0 c=500 chunks=1 len=1024 type='bytes' benchmarker='wrk' *** 9.20 % ±0.99% ±1.32% ±1.72%
http/simple.js duration=5 chunkedEnc=0 c=500 chunks=1 len=102400 type='buffer' benchmarker='wrk' *** 1.28 % ±0.53% ±0.71% ±0.93%
http/simple.js duration=5 chunkedEnc=0 c=500 chunks=1 len=102400 type='bytes' benchmarker='wrk' *** 1.28 % ±0.65% ±0.87% ±1.13%
http/simple.js duration=5 chunkedEnc=0 c=500 chunks=1 len=4 type='buffer' benchmarker='wrk' *** 3.59 % ±0.96% ±1.28% ±1.67%
http/simple.js duration=5 chunkedEnc=0 c=500 chunks=1 len=4 type='bytes' benchmarker='wrk' *** 9.93 % ±1.01% ±1.35% ±1.76%
http/simple.js duration=5 chunkedEnc=0 c=500 chunks=4 len=1024 type='buffer' benchmarker='wrk' *** 2.04 % ±0.98% ±1.31% ±1.70%
http/simple.js duration=5 chunkedEnc=0 c=500 chunks=4 len=1024 type='bytes' benchmarker='wrk' *** 2.14 % ±0.82% ±1.08% ±1.41%
http/simple.js duration=5 chunkedEnc=0 c=500 chunks=4 len=102400 type='buffer' benchmarker='wrk' *** 1.74 % ±0.67% ±0.89% ±1.16%
http/simple.js duration=5 chunkedEnc=0 c=500 chunks=4 len=102400 type='bytes' benchmarker='wrk' ** 1.10 % ±0.79% ±1.05% ±1.36%
http/simple.js duration=5 chunkedEnc=0 c=500 chunks=4 len=4 type='buffer' benchmarker='wrk' *** 3.20 % ±0.94% ±1.24% ±1.62%
http/simple.js duration=5 chunkedEnc=0 c=500 chunks=4 len=4 type='bytes' benchmarker='wrk' *** 3.12 % ±0.76% ±1.01% ±1.32%
http/simple.js duration=5 chunkedEnc=1 c=50 chunks=1 len=1024 type='buffer' benchmarker='wrk' -0.19 % ±0.80% ±1.06% ±1.38%
http/simple.js duration=5 chunkedEnc=1 c=50 chunks=1 len=1024 type='bytes' benchmarker='wrk' -0.44 % ±0.95% ±1.26% ±1.65%
http/simple.js duration=5 chunkedEnc=1 c=50 chunks=1 len=102400 type='buffer' benchmarker='wrk' 0.11 % ±0.61% ±0.81% ±1.06%
http/simple.js duration=5 chunkedEnc=1 c=50 chunks=1 len=102400 type='bytes' benchmarker='wrk' * -1.19 % ±1.11% ±1.47% ±1.92%
http/simple.js duration=5 chunkedEnc=1 c=50 chunks=1 len=4 type='buffer' benchmarker='wrk' -0.23 % ±0.80% ±1.07% ±1.39%
http/simple.js duration=5 chunkedEnc=1 c=50 chunks=1 len=4 type='bytes' benchmarker='wrk' 0.10 % ±0.75% ±1.00% ±1.30%
http/simple.js duration=5 chunkedEnc=1 c=50 chunks=4 len=1024 type='buffer' benchmarker='wrk' -0.55 % ±0.76% ±1.01% ±1.32%
http/simple.js duration=5 chunkedEnc=1 c=50 chunks=4 len=1024 type='bytes' benchmarker='wrk' 0.19 % ±0.95% ±1.27% ±1.65%
http/simple.js duration=5 chunkedEnc=1 c=50 chunks=4 len=102400 type='buffer' benchmarker='wrk' ** -1.32 % ±0.79% ±1.06% ±1.37%
http/simple.js duration=5 chunkedEnc=1 c=50 chunks=4 len=102400 type='bytes' benchmarker='wrk' 0.69 % ±1.07% ±1.42% ±1.85%
http/simple.js duration=5 chunkedEnc=1 c=50 chunks=4 len=4 type='buffer' benchmarker='wrk' 0.54 % ±0.81% ±1.07% ±1.40%
http/simple.js duration=5 chunkedEnc=1 c=50 chunks=4 len=4 type='bytes' benchmarker='wrk' 0.56 % ±0.71% ±0.95% ±1.23%
http/simple.js duration=5 chunkedEnc=1 c=500 chunks=1 len=1024 type='buffer' benchmarker='wrk' -0.48 % ±0.80% ±1.07% ±1.39%
http/simple.js duration=5 chunkedEnc=1 c=500 chunks=1 len=1024 type='bytes' benchmarker='wrk' -0.62 % ±0.85% ±1.13% ±1.48%
http/simple.js duration=5 chunkedEnc=1 c=500 chunks=1 len=102400 type='buffer' benchmarker='wrk' -0.20 % ±0.69% ±0.92% ±1.20%
http/simple.js duration=5 chunkedEnc=1 c=500 chunks=1 len=102400 type='bytes' benchmarker='wrk' 0.43 % ±1.18% ±1.56% ±2.04%
http/simple.js duration=5 chunkedEnc=1 c=500 chunks=1 len=4 type='buffer' benchmarker='wrk' 0.29 % ±0.89% ±1.19% ±1.55%
http/simple.js duration=5 chunkedEnc=1 c=500 chunks=1 len=4 type='bytes' benchmarker='wrk' * -1.01 % ±0.80% ±1.07% ±1.39%
http/simple.js duration=5 chunkedEnc=1 c=500 chunks=4 len=1024 type='buffer' benchmarker='wrk' -0.18 % ±0.68% ±0.90% ±1.18%
http/simple.js duration=5 chunkedEnc=1 c=500 chunks=4 len=1024 type='bytes' benchmarker='wrk' 0.09 % ±0.65% ±0.86% ±1.12%
http/simple.js duration=5 chunkedEnc=1 c=500 chunks=4 len=102400 type='buffer' benchmarker='wrk' * -0.55 % ±0.49% ±0.66% ±0.86%
http/simple.js duration=5 chunkedEnc=1 c=500 chunks=4 len=102400 type='bytes' benchmarker='wrk' 0.10 % ±0.82% ±1.09% ±1.42%
http/simple.js duration=5 chunkedEnc=1 c=500 chunks=4 len=4 type='buffer' benchmarker='wrk' 0.35 % ±0.74% ±0.98% ±1.28%
http/simple.js duration=5 chunkedEnc=1 c=500 chunks=4 len=4 type='bytes' benchmarker='wrk' -0.26 % ±0.65% ±0.86% ±1.12%
http/upgrade.js n=1000 0.73 % ±2.37% ±3.16% ±4.11%
http/upgrade.js n=5 6.72 % ±8.30% ±11.05% ±14.38%

Be aware that when doing many comparisons the risk of a false-positive result increases.

In this case, there are 235 comparisons, you can thus expect the following amount of false-positive results:

11.75 false positives, when considering a 5% risk acceptance (*, **, *),

2.35 false positives, when considering a 1% risk acceptance (, ),

0.24 false positives, when considering a 0.1% risk acceptance ()
Looks good I think. Headlines:
  • No notable regressions - each of the small negative cases I can see are low-confidence and fit into an overall pattern of no change considering the tests around them
  • A very consistent 9.59% - 9.87% speed up in http/set-header.js test, which tests headers + res.end(body).
  • For http/simple:

    • Consistent boost around 9.5% with type=bytes, no chunking, and len up to 1024.
    • 3% boost with type=buffer, on the same small non-chunked responses.
    • Both buffer & byte body perf dropping to about 1-2% improvement for larger bodies (1MB).
    • No significant change with chunked encoding.
  • 10.48% boost to http/end-string test with 1KB, dropping to 5.59% with 16KB, down to 2.47% improvement with 1MB.
  • ~2% boost across various http/end-vs-write-end.js cases that call end(data) on different large sizes.
Looks pretty convincing to me! All approved and ready-to-go now and I think this is all just good news, so I'll commit-queue.
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@pimterry@aduh95
http: improve performance with known-length calls to end()
89ac179
This boosts RPS performance for the common API case where you call
`res.end(data)` with the entire response by up to 9%.
Signed-off-by: Tim Perry <pimterry@gmail.com>
PR-URL: #65466
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
Reviewed-By: Yagiz Nizipli <yagiz@nizipli.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Gürgün Dayıoğlu <hey@gurgun.day>
aduh95 pushed a commit
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@pimterry@aduh95
http: improve performance with known-length calls to end()
c2c31d6
This boosts RPS performance for the common API case where you call
`res.end(data)` with the entire response by up to 9%.
Signed-off-by: Tim Perry <pimterry@gmail.com>
PR-URL: #65466
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
Reviewed-By: Yagiz Nizipli <yagiz@nizipli.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Gürgün Dayıoğlu <hey@gurgun.day>
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aduh95 pushed a commit
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@pimterry@aduh95
http: improve performance with known-length calls to end()
5b13d30
This boosts RPS performance for the common API case where you call
`res.end(data)` with the entire response by up to 9%.
Signed-off-by: Tim Perry <pimterry@gmail.com>
PR-URL: #65466
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
Reviewed-By: Yagiz Nizipli <yagiz@nizipli.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Gürgün Dayıoğlu <hey@gurgun.day>
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, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Remove or un-stick sticky/fixed headers that block content\n(function() {\n function unstick() {\n document.querySelectorAll('header, nav, [role=\"banner\"], .header, .navbar, .sticky, .fixed-top, [style*=\"position: fixed\"], [style*=\"position:sticky\"]').forEach(function(el) {\n if (el.style.position === 'fixed' || el.style.position === 'sticky' || \n getComputedStyle(el).position === 'fixed' || getComputedStyle(el).position === 'sticky') {\n el.style.position = 'static';\n el.style.top = 'auto';\n el.style.zIndex = 'auto';\n }\n });\n }\n \n unstick();\n \n var observer = new MutationObserver(unstick);\n observer.observe(document.body, { childList: true, subtree: true, attributes: true, attributeFilter: ['style', 'class'] });\n})();", "Kill Sticky Headers");
}
} catch(__e) { console.warn('[Userscript:Kill Sticky Headers]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

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http: improve performance for end() with known-length string - #65466
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When you call end(data) on an outgoing HTTP request, we previously wrote the data, and then ran _send('', ...) just to trigger flushing the headers, which resulted in an extra zero-byte write call and bonus nextTick before 'finish'.
When the length is known and content-length is used (not chunking, so we don't need a terminator) we can skip this completely: prep the content-length header explicitly, and combine the finish into the existing write step.
This drops a nextTick, and goes from 2 write calls to 1 for the very common case of response.end(data) with a string, and for buffer data goes from 3 writes to 2.
In practice, in the tiny benchmark here which I think represents a very common use case (small API responses) I see this boosting HTTP RPS by up to 9% for writes up to 1KB or so. For larger responses the response write time starts to outweigh this, but I still see 3% RPS boost at 16KB. Needs autocannon to hit the rates required, you can test yourself with:
node benchmark/compare.js --old ./node-main --new ./node-pr --runs 20 --set benchmarker=autocannon --filter end-string http
Added a new test confirming the specific details and edge cases this touches, and updated one existing test which specifically asserted that end(data) triggered two writes, including the empty one.
@pimterry
http: improve performance with known-length calls to end()
659d6b9
This boosts RPS performance for the common API case where you call
`res.end(data)` with the entire response by up to 9%.
Signed-off-by: Tim Perry <pimterry@gmail.com>
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lgtm
@mcollina
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Aug 21, 2026•

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Codecov Report
✅ All modified and coverable lines are covered by tests.

✅ Project coverage is 90.13%. Comparing base (15940ef) to head (659d6b9).
⚠️ Report is 61 commits behind head on main.
Additional details and impacted files
@@ Coverage Diff @@## main #65466 +/- ##
==========================================
- Coverage 90.14% 90.13% -0.01% 
==========================================
Files 751 751 Lines 252298 252333 +35 Branches 47446 47449 +3 ==========================================
+ Hits 227436 227451 +15 - Misses 16175 16186 +11 - Partials 8687 8696 +9 
Files with missing linesCoverage Δ
lib/_http_outgoing.js97.76% <100.00%> (-0.02%)⬇️
... and 34 files with indirect coverage changes
 🚀 New features to boost your workflow: 
  • ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.
  • 📦 JS Bundle Analysis: Save yourself from yourself by tracking and limiting bundle sizes in JS merges.
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CI: https://ci.nodejs.org/job/node-test-pull-request/76211/
@bjohansebasbjohansebas
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@bjohansebas benchmark label was a good suggestion. I've done a run here.
Unfortunately it seems like the microbenchmark job is broken generally (cc @nodejs/build) and all recent jobs have failed with:
++ Rscript benchmark/compare.R
Error: package or namespace load failed for ‘ggplot2’ in dyn.load(file, DLLpath = DLLpath, ...):
unable to load shared object '/usr/local/lib/R/site-library/rlang/libs/rlang.so':
/usr/local/lib/R/site-library/rlang/libs/rlang.so: undefined symbol: SETLENGTH
Execution halted

I've manually extracted the CSV from the console output to get some numbers though, and run node-benchmark-compare on the result, which gives:
Details
 confidence improvement accuracy (*) (**) (***)
http/bench-parser-fragmented.js n=100000 frags=2 len=16 -0.20 % ±1.06% ±1.42% ±1.85%
http/bench-parser-fragmented.js n=100000 frags=2 len=8 -0.01 % ±0.94% ±1.25% ±1.63%
http/bench-parser-fragmented.js n=100000 frags=4 len=16 -0.17 % ±0.77% ±1.02% ±1.33%
http/bench-parser-fragmented.js n=100000 frags=4 len=8 -0.57 % ±0.64% ±0.85% ±1.11%
http/bench-parser-fragmented.js n=100000 frags=8 len=16 -0.07 % ±0.84% ±1.12% ±1.45%
http/bench-parser-fragmented.js n=100000 frags=8 len=8 0.43 % ±0.78% ±1.04% ±1.35%
http/bench-parser.js n=100000 len=16 0.20 % ±0.93% ±1.24% ±1.61%
http/bench-parser.js n=100000 len=32 0.03 % ±0.68% ±0.90% ±1.17%
http/bench-parser.js n=100000 len=4 0.60 % ±1.08% ±1.43% ±1.86%
http/bench-parser.js n=100000 len=8 0.32 % ±1.11% ±1.47% ±1.92%
http/check_invalid_header_char.js n=1000000 input='' 1.25 % ±2.48% ±3.30% ±4.30%
http/check_invalid_header_char.js n=1000000 input='\t\t\t\t\t\t\t\t\t\tFoo bar baz' 0.39 % ±1.66% ±2.21% ±2.88%
http/check_invalid_header_char.js n=1000000 input='\x7F' * 4.92 % ±3.90% ±5.19% ±6.75%
http/check_invalid_header_char.js n=1000000 input='1' -0.41 % ±3.47% ±4.62% ±6.02%
http/check_invalid_header_char.js n=1000000 input='20091' -0.50 % ±3.85% ±5.12% ±6.66%
http/check_invalid_header_char.js n=1000000 input='close' 0.49 % ±3.34% ±4.44% ±5.78%
http/check_invalid_header_char.js n=1000000 input='en-US' -0.66 % ±3.59% ±4.77% ±6.21%
http/check_invalid_header_char.js n=1000000 input='foo\nbar' -1.88 % ±2.70% ±3.60% ±4.70%
http/check_invalid_header_char.js n=1000000 input='group_acmeair' 0.85 % ±1.82% ±2.42% ±3.16%
http/check_invalid_header_char.js n=1000000 input='gzip' -0.60 % ±3.29% ±4.37% ±5.70%
http/check_invalid_header_char.js n=1000000 input='keep-alive' -1.28 % ±2.16% ±2.88% ±3.75%
http/check_invalid_header_char.js n=1000000 input='LONG_AND_INVALID' 0.08 % ±1.13% ±1.51% ±1.97%
http/check_invalid_header_char.js n=1000000 input='private' 1.00 % ±2.68% ±3.57% ±4.65%
http/check_invalid_header_char.js n=1000000 input='SAMEORIGIN' 1.36 % ±2.81% ±3.74% ±4.88%
http/check_invalid_header_char.js n=1000000 input='Sat, 07 May 2016 16:54:48 GMT' 0.79 % ±1.41% ±1.87% ±2.44%
http/check_invalid_header_char.js n=1000000 input='text/html; charset=utf-8' -0.12 % ±1.41% ±1.88% ±2.45%
http/check_invalid_header_char.js n=1000000 input='text/plain' -1.49 % ±2.96% ±3.95% ±5.14%
http/check_invalid_header_char.js n=1000000 input='中文呢' 1.95 % ±2.71% ±3.61% ±4.69%
http/check_is_http_token.js n=1000000 key=':' -0.22 % ±2.22% ±2.96% ±3.85%
http/check_is_http_token.js n=1000000 key=':alternate-protocol' 2.82 % ±4.07% ±5.42% ±7.06%
http/check_is_http_token.js n=1000000 key='((((())))' -1.22 % ±2.75% ±3.71% ±4.91%
http/check_is_http_token.js n=1000000 key='@@' 0.52 % ±2.14% ±2.85% ±3.71%
http/check_is_http_token.js n=1000000 key='Accept-Ranges' 0.51 % ±2.25% ±2.99% ±3.90%
http/check_is_http_token.js n=1000000 key='alt-svc' -0.09 % ±2.23% ±2.97% ±3.87%
http/check_is_http_token.js n=1000000 key='alternate-protocol:' -0.94 % ±2.08% ±2.77% ±3.61%
http/check_is_http_token.js n=1000000 key='alternate-protocol' -1.19 % ±2.32% ±3.09% ±4.03%
http/check_is_http_token.js n=1000000 key='Cache-Control' -0.96 % ±2.14% ±2.85% ±3.71%
http/check_is_http_token.js n=1000000 key='Connection' 0.78 % ±2.39% ±3.19% ±4.15%
http/check_is_http_token.js n=1000000 key='Content-Encoding' * -2.76 % ±2.26% ±3.01% ±3.92%
http/check_is_http_token.js n=1000000 key='content-length' 0.93 % ±2.27% ±3.02% ±3.92%
http/check_is_http_token.js n=1000000 key='Content-Location' -0.15 % ±2.52% ±3.35% ±4.36%
http/check_is_http_token.js n=1000000 key='content-type' -0.49 % ±2.55% ±3.39% ±4.41%
http/check_is_http_token.js n=1000000 key='Content-Type' 0.46 % ±2.58% ±3.43% ±4.47%
http/check_is_http_token.js n=1000000 key='date' 0.62 % ±2.42% ±3.22% ±4.19%
http/check_is_http_token.js n=1000000 key='ETag' -2.60 % ±3.97% ±5.32% ±7.01%
http/check_is_http_token.js n=1000000 key='Expires' ** 3.69 % ±2.64% ±3.52% ±4.59%
http/check_is_http_token.js n=1000000 key='Keep-Alive' -0.03 % ±2.59% ±3.45% ±4.48%
http/check_is_http_token.js n=1000000 key='Last-Modified' -0.99 % ±2.34% ±3.12% ±4.07%
http/check_is_http_token.js n=1000000 key='location' 0.79 % ±2.44% ±3.25% ±4.23%
http/check_is_http_token.js n=1000000 key='server' 0.37 % ±2.46% ±3.27% ±4.25%
http/check_is_http_token.js n=1000000 key='Server' * 3.70 % ±3.00% ±4.00% ±5.23%
http/check_is_http_token.js n=1000000 key='status' ** -4.32 % ±3.09% ±4.13% ±5.40%
http/check_is_http_token.js n=1000000 key='TCN' -0.86 % ±1.00% ±1.33% ±1.73%
http/check_is_http_token.js n=1000000 key='Transfer-Encoding' -1.00 % ±2.32% ±3.09% ±4.02%
http/check_is_http_token.js n=1000000 key='Vary' -0.56 % ±1.47% ±1.95% ±2.54%
http/check_is_http_token.js n=1000000 key='version' 1.90 % ±2.74% ±3.65% ±4.75%
http/check_is_http_token.js n=1000000 key='x-frame-options' 0.57 % ±2.05% ±2.73% ±3.55%
http/check_is_http_token.js n=1000000 key='x-xss-protection' -1.39 % ±2.29% ±3.06% ±3.99%
http/check_is_http_token.js n=1000000 key='中文呢' -1.00 % ±4.47% ±6.01% ±7.92%
http/chunked.js duration=5 c=100 len=1 n=1 benchmarker='wrk' -0.19 % ±0.68% ±0.91% ±1.18%
http/chunked.js duration=5 c=100 len=1 n=16 benchmarker='wrk' 0.41 % ±0.78% ±1.03% ±1.35%
http/chunked.js duration=5 c=100 len=1 n=4 benchmarker='wrk' 0.61 % ±2.08% ±2.76% ±3.60%
http/chunked.js duration=5 c=100 len=1 n=8 benchmarker='wrk' 0.13 % ±0.81% ±1.07% ±1.40%
http/chunked.js duration=5 c=100 len=256 n=1 benchmarker='wrk' -0.10 % ±0.70% ±0.93% ±1.21%
http/chunked.js duration=5 c=100 len=256 n=16 benchmarker='wrk' -0.70 % ±0.73% ±0.97% ±1.26%
http/chunked.js duration=5 c=100 len=256 n=4 benchmarker='wrk' -0.58 % ±1.84% ±2.45% ±3.18%
http/chunked.js duration=5 c=100 len=256 n=8 benchmarker='wrk' 0.11 % ±0.87% ±1.16% ±1.51%
http/chunked.js duration=5 c=100 len=64 n=1 benchmarker='wrk' -0.26 % ±0.60% ±0.80% ±1.04%
http/chunked.js duration=5 c=100 len=64 n=16 benchmarker='wrk' 0.56 % ±0.63% ±0.84% ±1.10%
http/chunked.js duration=5 c=100 len=64 n=4 benchmarker='wrk' 0.08 % ±1.81% ±2.41% ±3.15%
http/chunked.js duration=5 c=100 len=64 n=8 benchmarker='wrk' 0.26 % ±0.75% ±1.00% ±1.30%
http/client-request-body.js method='end' len=1024 type='asc' dur=5 -0.06 % ±0.69% ±0.92% ±1.20%
http/client-request-body.js method='end' len=1024 type='buf' dur=5 0.01 % ±0.76% ±1.02% ±1.32%
http/client-request-body.js method='end' len=1024 type='utf' dur=5 -0.28 % ±0.59% ±0.79% ±1.03%
http/client-request-body.js method='end' len=256 type='asc' dur=5 -0.49 % ±0.67% ±0.90% ±1.17%
http/client-request-body.js method='end' len=256 type='buf' dur=5 * -0.75 % ±0.68% ±0.90% ±1.18%
http/client-request-body.js method='end' len=256 type='utf' dur=5 0.03 % ±0.62% ±0.83% ±1.08%
http/client-request-body.js method='end' len=32 type='asc' dur=5 -0.01 % ±0.56% ±0.75% ±0.98%
http/client-request-body.js method='end' len=32 type='buf' dur=5 -0.37 % ±0.60% ±0.79% ±1.03%
http/client-request-body.js method='end' len=32 type='utf' dur=5 -0.16 % ±0.62% ±0.83% ±1.08%
http/client-request-body.js method='write' len=1024 type='asc' dur=5 -0.16 % ±0.78% ±1.03% ±1.34%
http/client-request-body.js method='write' len=1024 type='buf' dur=5 -0.34 % ±0.68% ±0.90% ±1.17%
http/client-request-body.js method='write' len=1024 type='utf' dur=5 0.06 % ±0.78% ±1.04% ±1.35%
http/client-request-body.js method='write' len=256 type='asc' dur=5 0.27 % ±0.70% ±0.93% ±1.21%
http/client-request-body.js method='write' len=256 type='buf' dur=5 0.09 % ±0.76% ±1.02% ±1.32%
http/client-request-body.js method='write' len=256 type='utf' dur=5 0.49 % ±0.59% ±0.79% ±1.03%
http/client-request-body.js method='write' len=32 type='asc' dur=5 -0.40 % ±0.64% ±0.86% ±1.11%
http/client-request-body.js method='write' len=32 type='buf' dur=5 -0.21 % ±0.65% ±0.86% ±1.12%
http/client-request-body.js method='write' len=32 type='utf' dur=5 0.02 % ±0.60% ±0.79% ±1.03%
http/cluster.js duration=5 c=50 len=1024 type='buffer' benchmarker='wrk' 0.13 % ±0.46% ±0.62% ±0.81%
http/cluster.js duration=5 c=50 len=1024 type='bytes' benchmarker='wrk' -0.11 % ±0.38% ±0.50% ±0.66%
http/cluster.js duration=5 c=50 len=102400 type='buffer' benchmarker='wrk' -0.24 % ±0.49% ±0.65% ±0.85%
http/cluster.js duration=5 c=50 len=102400 type='bytes' benchmarker='wrk' 0.14 % ±0.80% ±1.06% ±1.38%
http/cluster.js duration=5 c=50 len=4 type='buffer' benchmarker='wrk' -0.23 % ±0.29% ±0.39% ±0.51%
http/cluster.js duration=5 c=50 len=4 type='bytes' benchmarker='wrk' 0.00 % ±0.51% ±0.67% ±0.88%
http/cluster.js duration=5 c=500 len=1024 type='buffer' benchmarker='wrk' ** -0.77 % ±0.50% ±0.67% ±0.87%
http/cluster.js duration=5 c=500 len=1024 type='bytes' benchmarker='wrk' -0.18 % ±0.65% ±0.86% ±1.12%
http/cluster.js duration=5 c=500 len=102400 type='buffer' benchmarker='wrk' -0.18 % ±0.59% ±0.78% ±1.02%
http/cluster.js duration=5 c=500 len=102400 type='bytes' benchmarker='wrk' 0.28 % ±0.72% ±0.95% ±1.24%
http/cluster.js duration=5 c=500 len=4 type='buffer' benchmarker='wrk' -0.25 % ±0.47% ±0.62% ±0.81%
http/cluster.js duration=5 c=500 len=4 type='bytes' benchmarker='wrk' -0.36 % ±0.52% ±0.70% ±0.91%
http/create-clientrequest.js e=1 arg='options' url='idn' 2.09 % ±7.80% ±10.38% ±13.50%
http/create-clientrequest.js e=1 arg='options' url='long' -9.98 % ±14.10% ±18.77% ±24.46%
http/create-clientrequest.js e=1 arg='options' url='wpt' -4.69 % ±6.75% ±8.98% ±11.70%
http/create-clientrequest.js e=1 arg='string' url='idn' -4.15 % ±10.23% ±13.61% ±17.71%
http/create-clientrequest.js e=1 arg='string' url='long' -0.93 % ±12.77% ±16.99% ±22.12%
http/create-clientrequest.js e=1 arg='string' url='wpt' 0.60 % ±11.36% ±15.12% ±19.68%
http/create-clientrequest.js e=1 arg='URL' url='idn' 0.87 % ±9.17% ±12.20% ±15.88%
http/create-clientrequest.js e=1 arg='URL' url='long' -5.01 % ±10.02% ±13.35% ±17.41%
http/create-clientrequest.js e=1 arg='URL' url='wpt' 1.99 % ±8.00% ±10.64% ±13.85%
http/end-string.js duration=5 c=50 len=1024 benchmarker='wrk' *** 10.48 % ±0.81% ±1.08% ±1.41%
http/end-string.js duration=5 c=50 len=102400 benchmarker='wrk' *** 2.47 % ±0.50% ±0.66% ±0.86%
http/end-string.js duration=5 c=50 len=16384 benchmarker='wrk' *** 5.59 % ±0.89% ±1.19% ±1.55%
http/end-string.js duration=5 c=50 len=4 benchmarker='wrk' *** 9.92 % ±0.82% ±1.10% ±1.43%
http/end-string.js duration=5 c=50 len=64 benchmarker='wrk' *** 8.43 % ±0.71% ±0.94% ±1.23%
http/end-vs-write-end.js duration=5 method='end' c=100 len=1048576 type='asc' benchmarker='wrk' *** 2.48 % ±0.47% ±0.62% ±0.81%
http/end-vs-write-end.js duration=5 method='end' c=100 len=1048576 type='buf' benchmarker='wrk' -0.12 % ±0.43% ±0.57% ±0.74%
http/end-vs-write-end.js duration=5 method='end' c=100 len=1048576 type='utf' benchmarker='wrk' *** 0.68 % ±0.38% ±0.51% ±0.66%
http/end-vs-write-end.js duration=5 method='end' c=100 len=131072 type='asc' benchmarker='wrk' ** 1.19 % ±0.81% ±1.09% ±1.43%
http/end-vs-write-end.js duration=5 method='end' c=100 len=131072 type='buf' benchmarker='wrk' *** 1.50 % ±0.59% ±0.78% ±1.01%
http/end-vs-write-end.js duration=5 method='end' c=100 len=131072 type='utf' benchmarker='wrk' *** 2.25 % ±0.45% ±0.59% ±0.77%
http/end-vs-write-end.js duration=5 method='end' c=100 len=262144 type='asc' benchmarker='wrk' *** 1.18 % ±0.42% ±0.56% ±0.73%
http/end-vs-write-end.js duration=5 method='end' c=100 len=262144 type='buf' benchmarker='wrk' *** 0.92 % ±0.48% ±0.63% ±0.83%
http/end-vs-write-end.js duration=5 method='end' c=100 len=262144 type='utf' benchmarker='wrk' *** 1.25 % ±0.32% ±0.43% ±0.56%
http/end-vs-write-end.js duration=5 method='end' c=100 len=65536 type='asc' benchmarker='wrk' *** 1.60 % ±0.83% ±1.10% ±1.44%
http/end-vs-write-end.js duration=5 method='end' c=100 len=65536 type='buf' benchmarker='wrk' *** 2.34 % ±0.88% ±1.18% ±1.53%
http/end-vs-write-end.js duration=5 method='end' c=100 len=65536 type='utf' benchmarker='wrk' *** 2.95 % ±0.48% ±0.64% ±0.83%
http/end-vs-write-end.js duration=5 method='write' c=100 len=1048576 type='asc' benchmarker='wrk' -0.33 % ±0.57% ±0.77% ±1.00%
http/end-vs-write-end.js duration=5 method='write' c=100 len=1048576 type='buf' benchmarker='wrk' -0.16 % ±0.52% ±0.69% ±0.90%
http/end-vs-write-end.js duration=5 method='write' c=100 len=1048576 type='utf' benchmarker='wrk' -0.12 % ±0.36% ±0.47% ±0.62%
http/end-vs-write-end.js duration=5 method='write' c=100 len=131072 type='asc' benchmarker='wrk' 0.07 % ±0.76% ±1.01% ±1.32%
http/end-vs-write-end.js duration=5 method='write' c=100 len=131072 type='buf' benchmarker='wrk' -0.25 % ±0.51% ±0.68% ±0.89%
http/end-vs-write-end.js duration=5 method='write' c=100 len=131072 type='utf' benchmarker='wrk' 0.53 % ±1.00% ±1.34% ±1.74%
http/end-vs-write-end.js duration=5 method='write' c=100 len=262144 type='asc' benchmarker='wrk' -0.26 % ±0.61% ±0.81% ±1.06%
http/end-vs-write-end.js duration=5 method='write' c=100 len=262144 type='buf' benchmarker='wrk' -0.05 % ±0.47% ±0.62% ±0.81%
http/end-vs-write-end.js duration=5 method='write' c=100 len=262144 type='utf' benchmarker='wrk' -0.08 % ±0.56% ±0.74% ±0.96%
http/end-vs-write-end.js duration=5 method='write' c=100 len=65536 type='asc' benchmarker='wrk' -0.50 % ±0.96% ±1.28% ±1.66%
http/end-vs-write-end.js duration=5 method='write' c=100 len=65536 type='buf' benchmarker='wrk' -0.22 % ±0.71% ±0.94% ±1.23%
http/end-vs-write-end.js duration=5 method='write' c=100 len=65536 type='utf' benchmarker='wrk' 0.10 % ±0.58% ±0.77% ±1.01%
http/headers.js group='fewHeaders' duration=5 len=1 n=10 benchmarker='wrk' -0.23 % ±0.65% ±0.86% ±1.13%
http/headers.js group='fewHeaders' duration=5 len=5 n=10 benchmarker='wrk' 0.25 % ±0.59% ±0.79% ±1.03%
http/headers.js group='manyHeaders' duration=5 len=1 n=600 benchmarker='wrk' -0.11 % ±0.86% ±1.15% ±1.49%
http/headers.js group='manyHeaders' duration=5 len=100 n=600 benchmarker='wrk' 0.22 % ±1.12% ±1.49% ±1.94%
http/headers.js group='mediumHeaders' duration=5 len=1 n=50 benchmarker='wrk' -0.28 % ±0.51% ±0.67% ±0.88%
http/headers.js group='mediumHeaders' duration=5 len=10 n=50 benchmarker='wrk' 0.04 % ±0.53% ±0.71% ±0.93%
http/http_server_for_chunky_client.js type='send' n=2000 len=1 0.19 % ±0.57% ±0.77% ±1.00%
http/http_server_for_chunky_client.js type='send' n=2000 len=128 -0.12 % ±0.59% ±0.78% ±1.02%
http/http_server_for_chunky_client.js type='send' n=2000 len=16 -0.01 % ±0.60% ±0.79% ±1.03%
http/http_server_for_chunky_client.js type='send' n=2000 len=32 0.15 % ±0.61% ±0.81% ±1.06%
http/http_server_for_chunky_client.js type='send' n=2000 len=4 0.67 % ±0.69% ±0.92% ±1.21%
http/http_server_for_chunky_client.js type='send' n=2000 len=64 -0.30 % ±0.48% ±0.64% ±0.83%
http/http_server_for_chunky_client.js type='send' n=2000 len=8 -0.50 % ±0.55% ±0.73% ±0.95%
http/http_server_for_chunky_client.js type='send' n=5 len=1 -1.39 % ±2.60% ±3.47% ±4.51%
http/http_server_for_chunky_client.js type='send' n=5 len=128 -4.15 % ±13.02% ±17.32% ±22.54%
http/http_server_for_chunky_client.js type='send' n=5 len=16 7.54 % ±10.05% ±13.50% ±17.81%
http/http_server_for_chunky_client.js type='send' n=5 len=32 0.87 % ±11.95% ±15.91% ±20.71%
http/http_server_for_chunky_client.js type='send' n=5 len=4 1.73 % ±10.57% ±14.06% ±18.30%
http/http_server_for_chunky_client.js type='send' n=5 len=64 -5.12 % ±14.17% ±18.86% ±24.56%
http/http_server_for_chunky_client.js type='send' n=5 len=8 -2.55 % ±5.92% ±7.90% ±10.32%
http/http_server_for_chunky_client.js type='send' n=50 len=1 1.27 % ±2.86% ±3.81% ±4.96%
http/http_server_for_chunky_client.js type='send' n=50 len=128 * 5.17 % ±4.13% ±5.49% ±7.15%
http/http_server_for_chunky_client.js type='send' n=50 len=16 -0.71 % ±2.69% ±3.58% ±4.67%
http/http_server_for_chunky_client.js type='send' n=50 len=32 -0.12 % ±2.72% ±3.63% ±4.74%
http/http_server_for_chunky_client.js type='send' n=50 len=4 -1.47 % ±3.06% ±4.07% ±5.29%
http/http_server_for_chunky_client.js type='send' n=50 len=64 2.04 % ±3.51% ±4.67% ±6.09%
http/http_server_for_chunky_client.js type='send' n=50 len=8 -0.08 % ±2.21% ±2.94% ±3.84%
http/http_server_for_chunky_client.js type='send' n=500 len=1 -0.08 % ±0.80% ±1.07% ±1.40%
http/http_server_for_chunky_client.js type='send' n=500 len=128 -0.38 % ±0.70% ±0.93% ±1.21%
http/http_server_for_chunky_client.js type='send' n=500 len=16 * -0.94 % ±0.83% ±1.11% ±1.45%
http/http_server_for_chunky_client.js type='send' n=500 len=32 -0.43 % ±0.83% ±1.11% ±1.45%
http/http_server_for_chunky_client.js type='send' n=500 len=4 -0.02 % ±0.71% ±0.95% ±1.24%
http/http_server_for_chunky_client.js type='send' n=500 len=64 -0.19 % ±0.93% ±1.24% ±1.62%
http/http_server_for_chunky_client.js type='send' n=500 len=8 -0.15 % ±0.71% ±0.95% ±1.23%
http/incoming_headers.js duration=5 w=0 headers=20 connections=50 benchmarker='wrk' 0.04 % ±0.81% ±1.08% ±1.42%
http/incoming_headers.js duration=5 w=6 headers=20 connections=50 benchmarker='wrk' 0.04 % ±0.64% ±0.85% ±1.11%
http/set_header.js n=1000000 value='Connection' ** -2.20 % ±1.65% ±2.19% ±2.85%
http/set_header.js n=1000000 value='Content-Length' 0.29 % ±1.71% ±2.28% ±2.97%
http/set_header.js n=1000000 value='Content-Type' 1.33 % ±1.88% ±2.51% ±3.27%
http/set_header.js n=1000000 value='Set-Cookie' 1.14 % ±1.33% ±1.77% ±2.30%
http/set_header.js n=1000000 value='Transfer-Encoding' 1.06 % ±1.33% ±1.76% ±2.30%
http/set_header.js n=1000000 value='Vary' -0.57 % ±1.72% ±2.29% ±2.99%
http/set_header.js n=1000000 value='X-Powered-By' * 1.49 % ±1.33% ±1.77% ±2.30%
http/set-header.js duration=5 res='normal' benchmarker='wrk' *** 9.74 % ±0.78% ±1.04% ±1.35%
http/set-header.js duration=5 res='setHeader' benchmarker='wrk' *** 9.87 % ±0.83% ±1.10% ±1.44%
http/set-header.js duration=5 res='setHeaderWH' benchmarker='wrk' *** 9.59 % ±0.92% ±1.22% ±1.59%
http/simple.js duration=5 chunkedEnc=0 c=50 chunks=1 len=1024 type='buffer' benchmarker='wrk' *** 2.60 % ±0.75% ±1.00% ±1.30%
http/simple.js duration=5 chunkedEnc=0 c=50 chunks=1 len=1024 type='bytes' benchmarker='wrk' *** 9.54 % ±0.74% ±0.99% ±1.28%
http/simple.js duration=5 chunkedEnc=0 c=50 chunks=1 len=102400 type='buffer' benchmarker='wrk' ** 1.23 % ±0.75% ±0.99% ±1.29%
http/simple.js duration=5 chunkedEnc=0 c=50 chunks=1 len=102400 type='bytes' benchmarker='wrk' *** 1.98 % ±0.49% ±0.65% ±0.84%
http/simple.js duration=5 chunkedEnc=0 c=50 chunks=1 len=4 type='buffer' benchmarker='wrk' *** 2.43 % ±0.76% ±1.01% ±1.31%
http/simple.js duration=5 chunkedEnc=0 c=50 chunks=1 len=4 type='bytes' benchmarker='wrk' *** 9.55 % ±0.71% ±0.95% ±1.24%
http/simple.js duration=5 chunkedEnc=0 c=50 chunks=4 len=1024 type='buffer' benchmarker='wrk' *** 3.14 % ±0.86% ±1.15% ±1.50%
http/simple.js duration=5 chunkedEnc=0 c=50 chunks=4 len=1024 type='bytes' benchmarker='wrk' *** 2.94 % ±0.78% ±1.04% ±1.35%
http/simple.js duration=5 chunkedEnc=0 c=50 chunks=4 len=102400 type='buffer' benchmarker='wrk' *** 1.55 % ±0.62% ±0.82% ±1.07%
http/simple.js duration=5 chunkedEnc=0 c=50 chunks=4 len=102400 type='bytes' benchmarker='wrk' ** 1.10 % ±0.82% ±1.09% ±1.42%
http/simple.js duration=5 chunkedEnc=0 c=50 chunks=4 len=4 type='buffer' benchmarker='wrk' *** 3.91 % ±0.83% ±1.10% ±1.44%
http/simple.js duration=5 chunkedEnc=0 c=50 chunks=4 len=4 type='bytes' benchmarker='wrk' *** 3.47 % ±0.93% ±1.23% ±1.60%
http/simple.js duration=5 chunkedEnc=0 c=500 chunks=1 len=1024 type='buffer' benchmarker='wrk' *** 3.60 % ±0.96% ±1.27% ±1.66%
http/simple.js duration=5 chunkedEnc=0 c=500 chunks=1 len=1024 type='bytes' benchmarker='wrk' *** 9.20 % ±0.99% ±1.32% ±1.72%
http/simple.js duration=5 chunkedEnc=0 c=500 chunks=1 len=102400 type='buffer' benchmarker='wrk' *** 1.28 % ±0.53% ±0.71% ±0.93%
http/simple.js duration=5 chunkedEnc=0 c=500 chunks=1 len=102400 type='bytes' benchmarker='wrk' *** 1.28 % ±0.65% ±0.87% ±1.13%
http/simple.js duration=5 chunkedEnc=0 c=500 chunks=1 len=4 type='buffer' benchmarker='wrk' *** 3.59 % ±0.96% ±1.28% ±1.67%
http/simple.js duration=5 chunkedEnc=0 c=500 chunks=1 len=4 type='bytes' benchmarker='wrk' *** 9.93 % ±1.01% ±1.35% ±1.76%
http/simple.js duration=5 chunkedEnc=0 c=500 chunks=4 len=1024 type='buffer' benchmarker='wrk' *** 2.04 % ±0.98% ±1.31% ±1.70%
http/simple.js duration=5 chunkedEnc=0 c=500 chunks=4 len=1024 type='bytes' benchmarker='wrk' *** 2.14 % ±0.82% ±1.08% ±1.41%
http/simple.js duration=5 chunkedEnc=0 c=500 chunks=4 len=102400 type='buffer' benchmarker='wrk' *** 1.74 % ±0.67% ±0.89% ±1.16%
http/simple.js duration=5 chunkedEnc=0 c=500 chunks=4 len=102400 type='bytes' benchmarker='wrk' ** 1.10 % ±0.79% ±1.05% ±1.36%
http/simple.js duration=5 chunkedEnc=0 c=500 chunks=4 len=4 type='buffer' benchmarker='wrk' *** 3.20 % ±0.94% ±1.24% ±1.62%
http/simple.js duration=5 chunkedEnc=0 c=500 chunks=4 len=4 type='bytes' benchmarker='wrk' *** 3.12 % ±0.76% ±1.01% ±1.32%
http/simple.js duration=5 chunkedEnc=1 c=50 chunks=1 len=1024 type='buffer' benchmarker='wrk' -0.19 % ±0.80% ±1.06% ±1.38%
http/simple.js duration=5 chunkedEnc=1 c=50 chunks=1 len=1024 type='bytes' benchmarker='wrk' -0.44 % ±0.95% ±1.26% ±1.65%
http/simple.js duration=5 chunkedEnc=1 c=50 chunks=1 len=102400 type='buffer' benchmarker='wrk' 0.11 % ±0.61% ±0.81% ±1.06%
http/simple.js duration=5 chunkedEnc=1 c=50 chunks=1 len=102400 type='bytes' benchmarker='wrk' * -1.19 % ±1.11% ±1.47% ±1.92%
http/simple.js duration=5 chunkedEnc=1 c=50 chunks=1 len=4 type='buffer' benchmarker='wrk' -0.23 % ±0.80% ±1.07% ±1.39%
http/simple.js duration=5 chunkedEnc=1 c=50 chunks=1 len=4 type='bytes' benchmarker='wrk' 0.10 % ±0.75% ±1.00% ±1.30%
http/simple.js duration=5 chunkedEnc=1 c=50 chunks=4 len=1024 type='buffer' benchmarker='wrk' -0.55 % ±0.76% ±1.01% ±1.32%
http/simple.js duration=5 chunkedEnc=1 c=50 chunks=4 len=1024 type='bytes' benchmarker='wrk' 0.19 % ±0.95% ±1.27% ±1.65%
http/simple.js duration=5 chunkedEnc=1 c=50 chunks=4 len=102400 type='buffer' benchmarker='wrk' ** -1.32 % ±0.79% ±1.06% ±1.37%
http/simple.js duration=5 chunkedEnc=1 c=50 chunks=4 len=102400 type='bytes' benchmarker='wrk' 0.69 % ±1.07% ±1.42% ±1.85%
http/simple.js duration=5 chunkedEnc=1 c=50 chunks=4 len=4 type='buffer' benchmarker='wrk' 0.54 % ±0.81% ±1.07% ±1.40%
http/simple.js duration=5 chunkedEnc=1 c=50 chunks=4 len=4 type='bytes' benchmarker='wrk' 0.56 % ±0.71% ±0.95% ±1.23%
http/simple.js duration=5 chunkedEnc=1 c=500 chunks=1 len=1024 type='buffer' benchmarker='wrk' -0.48 % ±0.80% ±1.07% ±1.39%
http/simple.js duration=5 chunkedEnc=1 c=500 chunks=1 len=1024 type='bytes' benchmarker='wrk' -0.62 % ±0.85% ±1.13% ±1.48%
http/simple.js duration=5 chunkedEnc=1 c=500 chunks=1 len=102400 type='buffer' benchmarker='wrk' -0.20 % ±0.69% ±0.92% ±1.20%
http/simple.js duration=5 chunkedEnc=1 c=500 chunks=1 len=102400 type='bytes' benchmarker='wrk' 0.43 % ±1.18% ±1.56% ±2.04%
http/simple.js duration=5 chunkedEnc=1 c=500 chunks=1 len=4 type='buffer' benchmarker='wrk' 0.29 % ±0.89% ±1.19% ±1.55%
http/simple.js duration=5 chunkedEnc=1 c=500 chunks=1 len=4 type='bytes' benchmarker='wrk' * -1.01 % ±0.80% ±1.07% ±1.39%
http/simple.js duration=5 chunkedEnc=1 c=500 chunks=4 len=1024 type='buffer' benchmarker='wrk' -0.18 % ±0.68% ±0.90% ±1.18%
http/simple.js duration=5 chunkedEnc=1 c=500 chunks=4 len=1024 type='bytes' benchmarker='wrk' 0.09 % ±0.65% ±0.86% ±1.12%
http/simple.js duration=5 chunkedEnc=1 c=500 chunks=4 len=102400 type='buffer' benchmarker='wrk' * -0.55 % ±0.49% ±0.66% ±0.86%
http/simple.js duration=5 chunkedEnc=1 c=500 chunks=4 len=102400 type='bytes' benchmarker='wrk' 0.10 % ±0.82% ±1.09% ±1.42%
http/simple.js duration=5 chunkedEnc=1 c=500 chunks=4 len=4 type='buffer' benchmarker='wrk' 0.35 % ±0.74% ±0.98% ±1.28%
http/simple.js duration=5 chunkedEnc=1 c=500 chunks=4 len=4 type='bytes' benchmarker='wrk' -0.26 % ±0.65% ±0.86% ±1.12%
http/upgrade.js n=1000 0.73 % ±2.37% ±3.16% ±4.11%
http/upgrade.js n=5 6.72 % ±8.30% ±11.05% ±14.38%

Be aware that when doing many comparisons the risk of a false-positive result increases.

In this case, there are 235 comparisons, you can thus expect the following amount of false-positive results:

11.75 false positives, when considering a 5% risk acceptance (*, **, *),

2.35 false positives, when considering a 1% risk acceptance (, ),

0.24 false positives, when considering a 0.1% risk acceptance ()
Looks good I think. Headlines:
  • No notable regressions - each of the small negative cases I can see are low-confidence and fit into an overall pattern of no change considering the tests around them
  • A very consistent 9.59% - 9.87% speed up in http/set-header.js test, which tests headers + res.end(body).
  • For http/simple:

    • Consistent boost around 9.5% with type=bytes, no chunking, and len up to 1024.
    • 3% boost with type=buffer, on the same small non-chunked responses.
    • Both buffer & byte body perf dropping to about 1-2% improvement for larger bodies (1MB).
    • No significant change with chunked encoding.
  • 10.48% boost to http/end-string test with 1KB, dropping to 5.59% with 16KB, down to 2.47% improvement with 1MB.
  • ~2% boost across various http/end-vs-write-end.js cases that call end(data) on different large sizes.
Looks pretty convincing to me! All approved and ready-to-go now and I think this is all just good news, so I'll commit-queue.
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http: improve performance with known-length calls to end()
89ac179
This boosts RPS performance for the common API case where you call
`res.end(data)` with the entire response by up to 9%.
Signed-off-by: Tim Perry <pimterry@gmail.com>
PR-URL: #65466
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
Reviewed-By: Yagiz Nizipli <yagiz@nizipli.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Gürgün Dayıoğlu <hey@gurgun.day>
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http: improve performance with known-length calls to end()
c2c31d6
This boosts RPS performance for the common API case where you call
`res.end(data)` with the entire response by up to 9%.
Signed-off-by: Tim Perry <pimterry@gmail.com>
PR-URL: #65466
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
Reviewed-By: Yagiz Nizipli <yagiz@nizipli.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Gürgün Dayıoğlu <hey@gurgun.day>
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@pimterry@aduh95
http: improve performance with known-length calls to end()
5b13d30
This boosts RPS performance for the common API case where you call
`res.end(data)` with the entire response by up to 9%.
Signed-off-by: Tim Perry <pimterry@gmail.com>
PR-URL: #65466
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
Reviewed-By: Yagiz Nizipli <yagiz@nizipli.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Gürgün Dayıoğlu <hey@gurgun.day>
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, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Universal Dark Mode - works on any site\n(function() {\n var enabled = true;\n \n function applyDarkMode() {\n if (!enabled) return;\n \n // Create style element if it doesn't exist\n var style = document.getElementById('universal-dark-mode-style');\n if (!style) {\n style = document.createElement('style');\n style.id = 'universal-dark-mode-style';\n document.head.appendChild(style);\n }\n \n // Dark mode CSS - inverts colors but preserves images/video\n style.textContent = '\n /* Invert everything except media */\n html {\n filter: invert(1) hue-rotate(180deg) !important;\n background: #1a1a2e !important;\n }\n \n /* Restore images, videos, iframes, canvas */\n img, video, iframe, canvas, svg, picture, [style*=\"background-image\"] {\n filter: invert(1) hue-rotate(180deg) !important;\n }\n \n /* Preserve specific elements that should not be inverted */\n .no-dark-mode, .no-dark-mode *,\n [data-theme=\"light\"], [data-theme=\"light\"],\n .ace_editor, .ace_editor *,\n .CodeMirror, .CodeMirror *,\n .monaco-editor, .monaco-editor *,\n .markdown-body pre, .markdown-body pre *,\n .highlight, .highlight *,\n pre code, pre code * {\n filter: none !important;\n }\n \n /* Fix common UI elements */\n .modal, .popup, .dropdown-menu, .tooltip, .popover {\n filter: invert(1) hue-rotate(180deg) !important;\n background: #2d2d44 !important;\n border-color: #444 !important;\n }\n \n /* Scrollbars */\n ::-webkit-scrollbar { background: #1a1a2e !important; }\n ::-webkit-scrollbar-thumb { background: #444 !important; }\n ::-webkit-scrollbar-thumb:hover { background: #555 !important; }\n \n /* Selection */\n ::selection { background: #4ecdc4 !important; color: #1a1a2e !important; }\n ::-moz-selection { background: #4ecdc4 !important; color: #1a1a2e !important; }\n ';\n }\n \n function removeDarkMode() {\n var style = document.getElementById('universal-dark-mode-style');\n if (style) style.remove();\n }\n \n // Toggle with Alt+Shift+D\n document.addEventListener('keydown', function(e) {\n if (e.altKey && e.shiftKey && e.key === 'D') {\n e.preventDefault();\n enabled = !enabled;\n if (enabled) {\n applyDarkMode();\n console.log('[Universal Dark Mode] Enabled');\n } else {\n removeDarkMode();\n console.log('[Universal Dark Mode] Disabled');\n }\n }\n });\n \n // Apply on load\n applyDarkMode();\n \n // Re-apply on dynamic content\n var observer = new MutationObserver(function(mutations) {\n if (enabled && !document.getElementById('universal-dark-mode-style')) {\n applyDarkMode();\n }\n });\n observer.observe(document.head, { childList: true });\n \n console.log('[Universal Dark Mode] Loaded - Press Alt+Shift+D to toggle');\n})();", "Universal Dark Mode");
}
} catch(__e) { console.warn('[Userscript:Universal Dark Mode]', __e); }
})();
})();

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http: improve performance for end() with known-length string - #65466
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When you call end(data) on an outgoing HTTP request, we previously wrote the data, and then ran _send('', ...) just to trigger flushing the headers, which resulted in an extra zero-byte write call and bonus nextTick before 'finish'.
When the length is known and content-length is used (not chunking, so we don't need a terminator) we can skip this completely: prep the content-length header explicitly, and combine the finish into the existing write step.
This drops a nextTick, and goes from 2 write calls to 1 for the very common case of response.end(data) with a string, and for buffer data goes from 3 writes to 2.
In practice, in the tiny benchmark here which I think represents a very common use case (small API responses) I see this boosting HTTP RPS by up to 9% for writes up to 1KB or so. For larger responses the response write time starts to outweigh this, but I still see 3% RPS boost at 16KB. Needs autocannon to hit the rates required, you can test yourself with:
node benchmark/compare.js --old ./node-main --new ./node-pr --runs 20 --set benchmarker=autocannon --filter end-string http
Added a new test confirming the specific details and edge cases this touches, and updated one existing test which specifically asserted that end(data) triggered two writes, including the empty one.
@pimterry
http: improve performance with known-length calls to end()
659d6b9
This boosts RPS performance for the common API case where you call
`res.end(data)` with the entire response by up to 9%.
Signed-off-by: Tim Perry <pimterry@gmail.com>
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lgtm
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Codecov Report
✅ All modified and coverable lines are covered by tests.

✅ Project coverage is 90.13%. Comparing base (15940ef) to head (659d6b9).
⚠️ Report is 61 commits behind head on main.
Additional details and impacted files
@@ Coverage Diff @@## main #65466 +/- ##
==========================================
- Coverage 90.14% 90.13% -0.01% 
==========================================
Files 751 751 Lines 252298 252333 +35 Branches 47446 47449 +3 ==========================================
+ Hits 227436 227451 +15 - Misses 16175 16186 +11 - Partials 8687 8696 +9 
Files with missing linesCoverage Δ
lib/_http_outgoing.js97.76% <100.00%> (-0.02%)⬇️
... and 34 files with indirect coverage changes
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  • ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.
  • 📦 JS Bundle Analysis: Save yourself from yourself by tracking and limiting bundle sizes in JS merges.
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CI: https://ci.nodejs.org/job/node-test-pull-request/76211/
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@bjohansebas benchmark label was a good suggestion. I've done a run here.
Unfortunately it seems like the microbenchmark job is broken generally (cc @nodejs/build) and all recent jobs have failed with:
++ Rscript benchmark/compare.R
Error: package or namespace load failed for ‘ggplot2’ in dyn.load(file, DLLpath = DLLpath, ...):
unable to load shared object '/usr/local/lib/R/site-library/rlang/libs/rlang.so':
/usr/local/lib/R/site-library/rlang/libs/rlang.so: undefined symbol: SETLENGTH
Execution halted

I've manually extracted the CSV from the console output to get some numbers though, and run node-benchmark-compare on the result, which gives:
Details
 confidence improvement accuracy (*) (**) (***)
http/bench-parser-fragmented.js n=100000 frags=2 len=16 -0.20 % ±1.06% ±1.42% ±1.85%
http/bench-parser-fragmented.js n=100000 frags=2 len=8 -0.01 % ±0.94% ±1.25% ±1.63%
http/bench-parser-fragmented.js n=100000 frags=4 len=16 -0.17 % ±0.77% ±1.02% ±1.33%
http/bench-parser-fragmented.js n=100000 frags=4 len=8 -0.57 % ±0.64% ±0.85% ±1.11%
http/bench-parser-fragmented.js n=100000 frags=8 len=16 -0.07 % ±0.84% ±1.12% ±1.45%
http/bench-parser-fragmented.js n=100000 frags=8 len=8 0.43 % ±0.78% ±1.04% ±1.35%
http/bench-parser.js n=100000 len=16 0.20 % ±0.93% ±1.24% ±1.61%
http/bench-parser.js n=100000 len=32 0.03 % ±0.68% ±0.90% ±1.17%
http/bench-parser.js n=100000 len=4 0.60 % ±1.08% ±1.43% ±1.86%
http/bench-parser.js n=100000 len=8 0.32 % ±1.11% ±1.47% ±1.92%
http/check_invalid_header_char.js n=1000000 input='' 1.25 % ±2.48% ±3.30% ±4.30%
http/check_invalid_header_char.js n=1000000 input='\t\t\t\t\t\t\t\t\t\tFoo bar baz' 0.39 % ±1.66% ±2.21% ±2.88%
http/check_invalid_header_char.js n=1000000 input='\x7F' * 4.92 % ±3.90% ±5.19% ±6.75%
http/check_invalid_header_char.js n=1000000 input='1' -0.41 % ±3.47% ±4.62% ±6.02%
http/check_invalid_header_char.js n=1000000 input='20091' -0.50 % ±3.85% ±5.12% ±6.66%
http/check_invalid_header_char.js n=1000000 input='close' 0.49 % ±3.34% ±4.44% ±5.78%
http/check_invalid_header_char.js n=1000000 input='en-US' -0.66 % ±3.59% ±4.77% ±6.21%
http/check_invalid_header_char.js n=1000000 input='foo\nbar' -1.88 % ±2.70% ±3.60% ±4.70%
http/check_invalid_header_char.js n=1000000 input='group_acmeair' 0.85 % ±1.82% ±2.42% ±3.16%
http/check_invalid_header_char.js n=1000000 input='gzip' -0.60 % ±3.29% ±4.37% ±5.70%
http/check_invalid_header_char.js n=1000000 input='keep-alive' -1.28 % ±2.16% ±2.88% ±3.75%
http/check_invalid_header_char.js n=1000000 input='LONG_AND_INVALID' 0.08 % ±1.13% ±1.51% ±1.97%
http/check_invalid_header_char.js n=1000000 input='private' 1.00 % ±2.68% ±3.57% ±4.65%
http/check_invalid_header_char.js n=1000000 input='SAMEORIGIN' 1.36 % ±2.81% ±3.74% ±4.88%
http/check_invalid_header_char.js n=1000000 input='Sat, 07 May 2016 16:54:48 GMT' 0.79 % ±1.41% ±1.87% ±2.44%
http/check_invalid_header_char.js n=1000000 input='text/html; charset=utf-8' -0.12 % ±1.41% ±1.88% ±2.45%
http/check_invalid_header_char.js n=1000000 input='text/plain' -1.49 % ±2.96% ±3.95% ±5.14%
http/check_invalid_header_char.js n=1000000 input='中文呢' 1.95 % ±2.71% ±3.61% ±4.69%
http/check_is_http_token.js n=1000000 key=':' -0.22 % ±2.22% ±2.96% ±3.85%
http/check_is_http_token.js n=1000000 key=':alternate-protocol' 2.82 % ±4.07% ±5.42% ±7.06%
http/check_is_http_token.js n=1000000 key='((((())))' -1.22 % ±2.75% ±3.71% ±4.91%
http/check_is_http_token.js n=1000000 key='@@' 0.52 % ±2.14% ±2.85% ±3.71%
http/check_is_http_token.js n=1000000 key='Accept-Ranges' 0.51 % ±2.25% ±2.99% ±3.90%
http/check_is_http_token.js n=1000000 key='alt-svc' -0.09 % ±2.23% ±2.97% ±3.87%
http/check_is_http_token.js n=1000000 key='alternate-protocol:' -0.94 % ±2.08% ±2.77% ±3.61%
http/check_is_http_token.js n=1000000 key='alternate-protocol' -1.19 % ±2.32% ±3.09% ±4.03%
http/check_is_http_token.js n=1000000 key='Cache-Control' -0.96 % ±2.14% ±2.85% ±3.71%
http/check_is_http_token.js n=1000000 key='Connection' 0.78 % ±2.39% ±3.19% ±4.15%
http/check_is_http_token.js n=1000000 key='Content-Encoding' * -2.76 % ±2.26% ±3.01% ±3.92%
http/check_is_http_token.js n=1000000 key='content-length' 0.93 % ±2.27% ±3.02% ±3.92%
http/check_is_http_token.js n=1000000 key='Content-Location' -0.15 % ±2.52% ±3.35% ±4.36%
http/check_is_http_token.js n=1000000 key='content-type' -0.49 % ±2.55% ±3.39% ±4.41%
http/check_is_http_token.js n=1000000 key='Content-Type' 0.46 % ±2.58% ±3.43% ±4.47%
http/check_is_http_token.js n=1000000 key='date' 0.62 % ±2.42% ±3.22% ±4.19%
http/check_is_http_token.js n=1000000 key='ETag' -2.60 % ±3.97% ±5.32% ±7.01%
http/check_is_http_token.js n=1000000 key='Expires' ** 3.69 % ±2.64% ±3.52% ±4.59%
http/check_is_http_token.js n=1000000 key='Keep-Alive' -0.03 % ±2.59% ±3.45% ±4.48%
http/check_is_http_token.js n=1000000 key='Last-Modified' -0.99 % ±2.34% ±3.12% ±4.07%
http/check_is_http_token.js n=1000000 key='location' 0.79 % ±2.44% ±3.25% ±4.23%
http/check_is_http_token.js n=1000000 key='server' 0.37 % ±2.46% ±3.27% ±4.25%
http/check_is_http_token.js n=1000000 key='Server' * 3.70 % ±3.00% ±4.00% ±5.23%
http/check_is_http_token.js n=1000000 key='status' ** -4.32 % ±3.09% ±4.13% ±5.40%
http/check_is_http_token.js n=1000000 key='TCN' -0.86 % ±1.00% ±1.33% ±1.73%
http/check_is_http_token.js n=1000000 key='Transfer-Encoding' -1.00 % ±2.32% ±3.09% ±4.02%
http/check_is_http_token.js n=1000000 key='Vary' -0.56 % ±1.47% ±1.95% ±2.54%
http/check_is_http_token.js n=1000000 key='version' 1.90 % ±2.74% ±3.65% ±4.75%
http/check_is_http_token.js n=1000000 key='x-frame-options' 0.57 % ±2.05% ±2.73% ±3.55%
http/check_is_http_token.js n=1000000 key='x-xss-protection' -1.39 % ±2.29% ±3.06% ±3.99%
http/check_is_http_token.js n=1000000 key='中文呢' -1.00 % ±4.47% ±6.01% ±7.92%
http/chunked.js duration=5 c=100 len=1 n=1 benchmarker='wrk' -0.19 % ±0.68% ±0.91% ±1.18%
http/chunked.js duration=5 c=100 len=1 n=16 benchmarker='wrk' 0.41 % ±0.78% ±1.03% ±1.35%
http/chunked.js duration=5 c=100 len=1 n=4 benchmarker='wrk' 0.61 % ±2.08% ±2.76% ±3.60%
http/chunked.js duration=5 c=100 len=1 n=8 benchmarker='wrk' 0.13 % ±0.81% ±1.07% ±1.40%
http/chunked.js duration=5 c=100 len=256 n=1 benchmarker='wrk' -0.10 % ±0.70% ±0.93% ±1.21%
http/chunked.js duration=5 c=100 len=256 n=16 benchmarker='wrk' -0.70 % ±0.73% ±0.97% ±1.26%
http/chunked.js duration=5 c=100 len=256 n=4 benchmarker='wrk' -0.58 % ±1.84% ±2.45% ±3.18%
http/chunked.js duration=5 c=100 len=256 n=8 benchmarker='wrk' 0.11 % ±0.87% ±1.16% ±1.51%
http/chunked.js duration=5 c=100 len=64 n=1 benchmarker='wrk' -0.26 % ±0.60% ±0.80% ±1.04%
http/chunked.js duration=5 c=100 len=64 n=16 benchmarker='wrk' 0.56 % ±0.63% ±0.84% ±1.10%
http/chunked.js duration=5 c=100 len=64 n=4 benchmarker='wrk' 0.08 % ±1.81% ±2.41% ±3.15%
http/chunked.js duration=5 c=100 len=64 n=8 benchmarker='wrk' 0.26 % ±0.75% ±1.00% ±1.30%
http/client-request-body.js method='end' len=1024 type='asc' dur=5 -0.06 % ±0.69% ±0.92% ±1.20%
http/client-request-body.js method='end' len=1024 type='buf' dur=5 0.01 % ±0.76% ±1.02% ±1.32%
http/client-request-body.js method='end' len=1024 type='utf' dur=5 -0.28 % ±0.59% ±0.79% ±1.03%
http/client-request-body.js method='end' len=256 type='asc' dur=5 -0.49 % ±0.67% ±0.90% ±1.17%
http/client-request-body.js method='end' len=256 type='buf' dur=5 * -0.75 % ±0.68% ±0.90% ±1.18%
http/client-request-body.js method='end' len=256 type='utf' dur=5 0.03 % ±0.62% ±0.83% ±1.08%
http/client-request-body.js method='end' len=32 type='asc' dur=5 -0.01 % ±0.56% ±0.75% ±0.98%
http/client-request-body.js method='end' len=32 type='buf' dur=5 -0.37 % ±0.60% ±0.79% ±1.03%
http/client-request-body.js method='end' len=32 type='utf' dur=5 -0.16 % ±0.62% ±0.83% ±1.08%
http/client-request-body.js method='write' len=1024 type='asc' dur=5 -0.16 % ±0.78% ±1.03% ±1.34%
http/client-request-body.js method='write' len=1024 type='buf' dur=5 -0.34 % ±0.68% ±0.90% ±1.17%
http/client-request-body.js method='write' len=1024 type='utf' dur=5 0.06 % ±0.78% ±1.04% ±1.35%
http/client-request-body.js method='write' len=256 type='asc' dur=5 0.27 % ±0.70% ±0.93% ±1.21%
http/client-request-body.js method='write' len=256 type='buf' dur=5 0.09 % ±0.76% ±1.02% ±1.32%
http/client-request-body.js method='write' len=256 type='utf' dur=5 0.49 % ±0.59% ±0.79% ±1.03%
http/client-request-body.js method='write' len=32 type='asc' dur=5 -0.40 % ±0.64% ±0.86% ±1.11%
http/client-request-body.js method='write' len=32 type='buf' dur=5 -0.21 % ±0.65% ±0.86% ±1.12%
http/client-request-body.js method='write' len=32 type='utf' dur=5 0.02 % ±0.60% ±0.79% ±1.03%
http/cluster.js duration=5 c=50 len=1024 type='buffer' benchmarker='wrk' 0.13 % ±0.46% ±0.62% ±0.81%
http/cluster.js duration=5 c=50 len=1024 type='bytes' benchmarker='wrk' -0.11 % ±0.38% ±0.50% ±0.66%
http/cluster.js duration=5 c=50 len=102400 type='buffer' benchmarker='wrk' -0.24 % ±0.49% ±0.65% ±0.85%
http/cluster.js duration=5 c=50 len=102400 type='bytes' benchmarker='wrk' 0.14 % ±0.80% ±1.06% ±1.38%
http/cluster.js duration=5 c=50 len=4 type='buffer' benchmarker='wrk' -0.23 % ±0.29% ±0.39% ±0.51%
http/cluster.js duration=5 c=50 len=4 type='bytes' benchmarker='wrk' 0.00 % ±0.51% ±0.67% ±0.88%
http/cluster.js duration=5 c=500 len=1024 type='buffer' benchmarker='wrk' ** -0.77 % ±0.50% ±0.67% ±0.87%
http/cluster.js duration=5 c=500 len=1024 type='bytes' benchmarker='wrk' -0.18 % ±0.65% ±0.86% ±1.12%
http/cluster.js duration=5 c=500 len=102400 type='buffer' benchmarker='wrk' -0.18 % ±0.59% ±0.78% ±1.02%
http/cluster.js duration=5 c=500 len=102400 type='bytes' benchmarker='wrk' 0.28 % ±0.72% ±0.95% ±1.24%
http/cluster.js duration=5 c=500 len=4 type='buffer' benchmarker='wrk' -0.25 % ±0.47% ±0.62% ±0.81%
http/cluster.js duration=5 c=500 len=4 type='bytes' benchmarker='wrk' -0.36 % ±0.52% ±0.70% ±0.91%
http/create-clientrequest.js e=1 arg='options' url='idn' 2.09 % ±7.80% ±10.38% ±13.50%
http/create-clientrequest.js e=1 arg='options' url='long' -9.98 % ±14.10% ±18.77% ±24.46%
http/create-clientrequest.js e=1 arg='options' url='wpt' -4.69 % ±6.75% ±8.98% ±11.70%
http/create-clientrequest.js e=1 arg='string' url='idn' -4.15 % ±10.23% ±13.61% ±17.71%
http/create-clientrequest.js e=1 arg='string' url='long' -0.93 % ±12.77% ±16.99% ±22.12%
http/create-clientrequest.js e=1 arg='string' url='wpt' 0.60 % ±11.36% ±15.12% ±19.68%
http/create-clientrequest.js e=1 arg='URL' url='idn' 0.87 % ±9.17% ±12.20% ±15.88%
http/create-clientrequest.js e=1 arg='URL' url='long' -5.01 % ±10.02% ±13.35% ±17.41%
http/create-clientrequest.js e=1 arg='URL' url='wpt' 1.99 % ±8.00% ±10.64% ±13.85%
http/end-string.js duration=5 c=50 len=1024 benchmarker='wrk' *** 10.48 % ±0.81% ±1.08% ±1.41%
http/end-string.js duration=5 c=50 len=102400 benchmarker='wrk' *** 2.47 % ±0.50% ±0.66% ±0.86%
http/end-string.js duration=5 c=50 len=16384 benchmarker='wrk' *** 5.59 % ±0.89% ±1.19% ±1.55%
http/end-string.js duration=5 c=50 len=4 benchmarker='wrk' *** 9.92 % ±0.82% ±1.10% ±1.43%
http/end-string.js duration=5 c=50 len=64 benchmarker='wrk' *** 8.43 % ±0.71% ±0.94% ±1.23%
http/end-vs-write-end.js duration=5 method='end' c=100 len=1048576 type='asc' benchmarker='wrk' *** 2.48 % ±0.47% ±0.62% ±0.81%
http/end-vs-write-end.js duration=5 method='end' c=100 len=1048576 type='buf' benchmarker='wrk' -0.12 % ±0.43% ±0.57% ±0.74%
http/end-vs-write-end.js duration=5 method='end' c=100 len=1048576 type='utf' benchmarker='wrk' *** 0.68 % ±0.38% ±0.51% ±0.66%
http/end-vs-write-end.js duration=5 method='end' c=100 len=131072 type='asc' benchmarker='wrk' ** 1.19 % ±0.81% ±1.09% ±1.43%
http/end-vs-write-end.js duration=5 method='end' c=100 len=131072 type='buf' benchmarker='wrk' *** 1.50 % ±0.59% ±0.78% ±1.01%
http/end-vs-write-end.js duration=5 method='end' c=100 len=131072 type='utf' benchmarker='wrk' *** 2.25 % ±0.45% ±0.59% ±0.77%
http/end-vs-write-end.js duration=5 method='end' c=100 len=262144 type='asc' benchmarker='wrk' *** 1.18 % ±0.42% ±0.56% ±0.73%
http/end-vs-write-end.js duration=5 method='end' c=100 len=262144 type='buf' benchmarker='wrk' *** 0.92 % ±0.48% ±0.63% ±0.83%
http/end-vs-write-end.js duration=5 method='end' c=100 len=262144 type='utf' benchmarker='wrk' *** 1.25 % ±0.32% ±0.43% ±0.56%
http/end-vs-write-end.js duration=5 method='end' c=100 len=65536 type='asc' benchmarker='wrk' *** 1.60 % ±0.83% ±1.10% ±1.44%
http/end-vs-write-end.js duration=5 method='end' c=100 len=65536 type='buf' benchmarker='wrk' *** 2.34 % ±0.88% ±1.18% ±1.53%
http/end-vs-write-end.js duration=5 method='end' c=100 len=65536 type='utf' benchmarker='wrk' *** 2.95 % ±0.48% ±0.64% ±0.83%
http/end-vs-write-end.js duration=5 method='write' c=100 len=1048576 type='asc' benchmarker='wrk' -0.33 % ±0.57% ±0.77% ±1.00%
http/end-vs-write-end.js duration=5 method='write' c=100 len=1048576 type='buf' benchmarker='wrk' -0.16 % ±0.52% ±0.69% ±0.90%
http/end-vs-write-end.js duration=5 method='write' c=100 len=1048576 type='utf' benchmarker='wrk' -0.12 % ±0.36% ±0.47% ±0.62%
http/end-vs-write-end.js duration=5 method='write' c=100 len=131072 type='asc' benchmarker='wrk' 0.07 % ±0.76% ±1.01% ±1.32%
http/end-vs-write-end.js duration=5 method='write' c=100 len=131072 type='buf' benchmarker='wrk' -0.25 % ±0.51% ±0.68% ±0.89%
http/end-vs-write-end.js duration=5 method='write' c=100 len=131072 type='utf' benchmarker='wrk' 0.53 % ±1.00% ±1.34% ±1.74%
http/end-vs-write-end.js duration=5 method='write' c=100 len=262144 type='asc' benchmarker='wrk' -0.26 % ±0.61% ±0.81% ±1.06%
http/end-vs-write-end.js duration=5 method='write' c=100 len=262144 type='buf' benchmarker='wrk' -0.05 % ±0.47% ±0.62% ±0.81%
http/end-vs-write-end.js duration=5 method='write' c=100 len=262144 type='utf' benchmarker='wrk' -0.08 % ±0.56% ±0.74% ±0.96%
http/end-vs-write-end.js duration=5 method='write' c=100 len=65536 type='asc' benchmarker='wrk' -0.50 % ±0.96% ±1.28% ±1.66%
http/end-vs-write-end.js duration=5 method='write' c=100 len=65536 type='buf' benchmarker='wrk' -0.22 % ±0.71% ±0.94% ±1.23%
http/end-vs-write-end.js duration=5 method='write' c=100 len=65536 type='utf' benchmarker='wrk' 0.10 % ±0.58% ±0.77% ±1.01%
http/headers.js group='fewHeaders' duration=5 len=1 n=10 benchmarker='wrk' -0.23 % ±0.65% ±0.86% ±1.13%
http/headers.js group='fewHeaders' duration=5 len=5 n=10 benchmarker='wrk' 0.25 % ±0.59% ±0.79% ±1.03%
http/headers.js group='manyHeaders' duration=5 len=1 n=600 benchmarker='wrk' -0.11 % ±0.86% ±1.15% ±1.49%
http/headers.js group='manyHeaders' duration=5 len=100 n=600 benchmarker='wrk' 0.22 % ±1.12% ±1.49% ±1.94%
http/headers.js group='mediumHeaders' duration=5 len=1 n=50 benchmarker='wrk' -0.28 % ±0.51% ±0.67% ±0.88%
http/headers.js group='mediumHeaders' duration=5 len=10 n=50 benchmarker='wrk' 0.04 % ±0.53% ±0.71% ±0.93%
http/http_server_for_chunky_client.js type='send' n=2000 len=1 0.19 % ±0.57% ±0.77% ±1.00%
http/http_server_for_chunky_client.js type='send' n=2000 len=128 -0.12 % ±0.59% ±0.78% ±1.02%
http/http_server_for_chunky_client.js type='send' n=2000 len=16 -0.01 % ±0.60% ±0.79% ±1.03%
http/http_server_for_chunky_client.js type='send' n=2000 len=32 0.15 % ±0.61% ±0.81% ±1.06%
http/http_server_for_chunky_client.js type='send' n=2000 len=4 0.67 % ±0.69% ±0.92% ±1.21%
http/http_server_for_chunky_client.js type='send' n=2000 len=64 -0.30 % ±0.48% ±0.64% ±0.83%
http/http_server_for_chunky_client.js type='send' n=2000 len=8 -0.50 % ±0.55% ±0.73% ±0.95%
http/http_server_for_chunky_client.js type='send' n=5 len=1 -1.39 % ±2.60% ±3.47% ±4.51%
http/http_server_for_chunky_client.js type='send' n=5 len=128 -4.15 % ±13.02% ±17.32% ±22.54%
http/http_server_for_chunky_client.js type='send' n=5 len=16 7.54 % ±10.05% ±13.50% ±17.81%
http/http_server_for_chunky_client.js type='send' n=5 len=32 0.87 % ±11.95% ±15.91% ±20.71%
http/http_server_for_chunky_client.js type='send' n=5 len=4 1.73 % ±10.57% ±14.06% ±18.30%
http/http_server_for_chunky_client.js type='send' n=5 len=64 -5.12 % ±14.17% ±18.86% ±24.56%
http/http_server_for_chunky_client.js type='send' n=5 len=8 -2.55 % ±5.92% ±7.90% ±10.32%
http/http_server_for_chunky_client.js type='send' n=50 len=1 1.27 % ±2.86% ±3.81% ±4.96%
http/http_server_for_chunky_client.js type='send' n=50 len=128 * 5.17 % ±4.13% ±5.49% ±7.15%
http/http_server_for_chunky_client.js type='send' n=50 len=16 -0.71 % ±2.69% ±3.58% ±4.67%
http/http_server_for_chunky_client.js type='send' n=50 len=32 -0.12 % ±2.72% ±3.63% ±4.74%
http/http_server_for_chunky_client.js type='send' n=50 len=4 -1.47 % ±3.06% ±4.07% ±5.29%
http/http_server_for_chunky_client.js type='send' n=50 len=64 2.04 % ±3.51% ±4.67% ±6.09%
http/http_server_for_chunky_client.js type='send' n=50 len=8 -0.08 % ±2.21% ±2.94% ±3.84%
http/http_server_for_chunky_client.js type='send' n=500 len=1 -0.08 % ±0.80% ±1.07% ±1.40%
http/http_server_for_chunky_client.js type='send' n=500 len=128 -0.38 % ±0.70% ±0.93% ±1.21%
http/http_server_for_chunky_client.js type='send' n=500 len=16 * -0.94 % ±0.83% ±1.11% ±1.45%
http/http_server_for_chunky_client.js type='send' n=500 len=32 -0.43 % ±0.83% ±1.11% ±1.45%
http/http_server_for_chunky_client.js type='send' n=500 len=4 -0.02 % ±0.71% ±0.95% ±1.24%
http/http_server_for_chunky_client.js type='send' n=500 len=64 -0.19 % ±0.93% ±1.24% ±1.62%
http/http_server_for_chunky_client.js type='send' n=500 len=8 -0.15 % ±0.71% ±0.95% ±1.23%
http/incoming_headers.js duration=5 w=0 headers=20 connections=50 benchmarker='wrk' 0.04 % ±0.81% ±1.08% ±1.42%
http/incoming_headers.js duration=5 w=6 headers=20 connections=50 benchmarker='wrk' 0.04 % ±0.64% ±0.85% ±1.11%
http/set_header.js n=1000000 value='Connection' ** -2.20 % ±1.65% ±2.19% ±2.85%
http/set_header.js n=1000000 value='Content-Length' 0.29 % ±1.71% ±2.28% ±2.97%
http/set_header.js n=1000000 value='Content-Type' 1.33 % ±1.88% ±2.51% ±3.27%
http/set_header.js n=1000000 value='Set-Cookie' 1.14 % ±1.33% ±1.77% ±2.30%
http/set_header.js n=1000000 value='Transfer-Encoding' 1.06 % ±1.33% ±1.76% ±2.30%
http/set_header.js n=1000000 value='Vary' -0.57 % ±1.72% ±2.29% ±2.99%
http/set_header.js n=1000000 value='X-Powered-By' * 1.49 % ±1.33% ±1.77% ±2.30%
http/set-header.js duration=5 res='normal' benchmarker='wrk' *** 9.74 % ±0.78% ±1.04% ±1.35%
http/set-header.js duration=5 res='setHeader' benchmarker='wrk' *** 9.87 % ±0.83% ±1.10% ±1.44%
http/set-header.js duration=5 res='setHeaderWH' benchmarker='wrk' *** 9.59 % ±0.92% ±1.22% ±1.59%
http/simple.js duration=5 chunkedEnc=0 c=50 chunks=1 len=1024 type='buffer' benchmarker='wrk' *** 2.60 % ±0.75% ±1.00% ±1.30%
http/simple.js duration=5 chunkedEnc=0 c=50 chunks=1 len=1024 type='bytes' benchmarker='wrk' *** 9.54 % ±0.74% ±0.99% ±1.28%
http/simple.js duration=5 chunkedEnc=0 c=50 chunks=1 len=102400 type='buffer' benchmarker='wrk' ** 1.23 % ±0.75% ±0.99% ±1.29%
http/simple.js duration=5 chunkedEnc=0 c=50 chunks=1 len=102400 type='bytes' benchmarker='wrk' *** 1.98 % ±0.49% ±0.65% ±0.84%
http/simple.js duration=5 chunkedEnc=0 c=50 chunks=1 len=4 type='buffer' benchmarker='wrk' *** 2.43 % ±0.76% ±1.01% ±1.31%
http/simple.js duration=5 chunkedEnc=0 c=50 chunks=1 len=4 type='bytes' benchmarker='wrk' *** 9.55 % ±0.71% ±0.95% ±1.24%
http/simple.js duration=5 chunkedEnc=0 c=50 chunks=4 len=1024 type='buffer' benchmarker='wrk' *** 3.14 % ±0.86% ±1.15% ±1.50%
http/simple.js duration=5 chunkedEnc=0 c=50 chunks=4 len=1024 type='bytes' benchmarker='wrk' *** 2.94 % ±0.78% ±1.04% ±1.35%
http/simple.js duration=5 chunkedEnc=0 c=50 chunks=4 len=102400 type='buffer' benchmarker='wrk' *** 1.55 % ±0.62% ±0.82% ±1.07%
http/simple.js duration=5 chunkedEnc=0 c=50 chunks=4 len=102400 type='bytes' benchmarker='wrk' ** 1.10 % ±0.82% ±1.09% ±1.42%
http/simple.js duration=5 chunkedEnc=0 c=50 chunks=4 len=4 type='buffer' benchmarker='wrk' *** 3.91 % ±0.83% ±1.10% ±1.44%
http/simple.js duration=5 chunkedEnc=0 c=50 chunks=4 len=4 type='bytes' benchmarker='wrk' *** 3.47 % ±0.93% ±1.23% ±1.60%
http/simple.js duration=5 chunkedEnc=0 c=500 chunks=1 len=1024 type='buffer' benchmarker='wrk' *** 3.60 % ±0.96% ±1.27% ±1.66%
http/simple.js duration=5 chunkedEnc=0 c=500 chunks=1 len=1024 type='bytes' benchmarker='wrk' *** 9.20 % ±0.99% ±1.32% ±1.72%
http/simple.js duration=5 chunkedEnc=0 c=500 chunks=1 len=102400 type='buffer' benchmarker='wrk' *** 1.28 % ±0.53% ±0.71% ±0.93%
http/simple.js duration=5 chunkedEnc=0 c=500 chunks=1 len=102400 type='bytes' benchmarker='wrk' *** 1.28 % ±0.65% ±0.87% ±1.13%
http/simple.js duration=5 chunkedEnc=0 c=500 chunks=1 len=4 type='buffer' benchmarker='wrk' *** 3.59 % ±0.96% ±1.28% ±1.67%
http/simple.js duration=5 chunkedEnc=0 c=500 chunks=1 len=4 type='bytes' benchmarker='wrk' *** 9.93 % ±1.01% ±1.35% ±1.76%
http/simple.js duration=5 chunkedEnc=0 c=500 chunks=4 len=1024 type='buffer' benchmarker='wrk' *** 2.04 % ±0.98% ±1.31% ±1.70%
http/simple.js duration=5 chunkedEnc=0 c=500 chunks=4 len=1024 type='bytes' benchmarker='wrk' *** 2.14 % ±0.82% ±1.08% ±1.41%
http/simple.js duration=5 chunkedEnc=0 c=500 chunks=4 len=102400 type='buffer' benchmarker='wrk' *** 1.74 % ±0.67% ±0.89% ±1.16%
http/simple.js duration=5 chunkedEnc=0 c=500 chunks=4 len=102400 type='bytes' benchmarker='wrk' ** 1.10 % ±0.79% ±1.05% ±1.36%
http/simple.js duration=5 chunkedEnc=0 c=500 chunks=4 len=4 type='buffer' benchmarker='wrk' *** 3.20 % ±0.94% ±1.24% ±1.62%
http/simple.js duration=5 chunkedEnc=0 c=500 chunks=4 len=4 type='bytes' benchmarker='wrk' *** 3.12 % ±0.76% ±1.01% ±1.32%
http/simple.js duration=5 chunkedEnc=1 c=50 chunks=1 len=1024 type='buffer' benchmarker='wrk' -0.19 % ±0.80% ±1.06% ±1.38%
http/simple.js duration=5 chunkedEnc=1 c=50 chunks=1 len=1024 type='bytes' benchmarker='wrk' -0.44 % ±0.95% ±1.26% ±1.65%
http/simple.js duration=5 chunkedEnc=1 c=50 chunks=1 len=102400 type='buffer' benchmarker='wrk' 0.11 % ±0.61% ±0.81% ±1.06%
http/simple.js duration=5 chunkedEnc=1 c=50 chunks=1 len=102400 type='bytes' benchmarker='wrk' * -1.19 % ±1.11% ±1.47% ±1.92%
http/simple.js duration=5 chunkedEnc=1 c=50 chunks=1 len=4 type='buffer' benchmarker='wrk' -0.23 % ±0.80% ±1.07% ±1.39%
http/simple.js duration=5 chunkedEnc=1 c=50 chunks=1 len=4 type='bytes' benchmarker='wrk' 0.10 % ±0.75% ±1.00% ±1.30%
http/simple.js duration=5 chunkedEnc=1 c=50 chunks=4 len=1024 type='buffer' benchmarker='wrk' -0.55 % ±0.76% ±1.01% ±1.32%
http/simple.js duration=5 chunkedEnc=1 c=50 chunks=4 len=1024 type='bytes' benchmarker='wrk' 0.19 % ±0.95% ±1.27% ±1.65%
http/simple.js duration=5 chunkedEnc=1 c=50 chunks=4 len=102400 type='buffer' benchmarker='wrk' ** -1.32 % ±0.79% ±1.06% ±1.37%
http/simple.js duration=5 chunkedEnc=1 c=50 chunks=4 len=102400 type='bytes' benchmarker='wrk' 0.69 % ±1.07% ±1.42% ±1.85%
http/simple.js duration=5 chunkedEnc=1 c=50 chunks=4 len=4 type='buffer' benchmarker='wrk' 0.54 % ±0.81% ±1.07% ±1.40%
http/simple.js duration=5 chunkedEnc=1 c=50 chunks=4 len=4 type='bytes' benchmarker='wrk' 0.56 % ±0.71% ±0.95% ±1.23%
http/simple.js duration=5 chunkedEnc=1 c=500 chunks=1 len=1024 type='buffer' benchmarker='wrk' -0.48 % ±0.80% ±1.07% ±1.39%
http/simple.js duration=5 chunkedEnc=1 c=500 chunks=1 len=1024 type='bytes' benchmarker='wrk' -0.62 % ±0.85% ±1.13% ±1.48%
http/simple.js duration=5 chunkedEnc=1 c=500 chunks=1 len=102400 type='buffer' benchmarker='wrk' -0.20 % ±0.69% ±0.92% ±1.20%
http/simple.js duration=5 chunkedEnc=1 c=500 chunks=1 len=102400 type='bytes' benchmarker='wrk' 0.43 % ±1.18% ±1.56% ±2.04%
http/simple.js duration=5 chunkedEnc=1 c=500 chunks=1 len=4 type='buffer' benchmarker='wrk' 0.29 % ±0.89% ±1.19% ±1.55%
http/simple.js duration=5 chunkedEnc=1 c=500 chunks=1 len=4 type='bytes' benchmarker='wrk' * -1.01 % ±0.80% ±1.07% ±1.39%
http/simple.js duration=5 chunkedEnc=1 c=500 chunks=4 len=1024 type='buffer' benchmarker='wrk' -0.18 % ±0.68% ±0.90% ±1.18%
http/simple.js duration=5 chunkedEnc=1 c=500 chunks=4 len=1024 type='bytes' benchmarker='wrk' 0.09 % ±0.65% ±0.86% ±1.12%
http/simple.js duration=5 chunkedEnc=1 c=500 chunks=4 len=102400 type='buffer' benchmarker='wrk' * -0.55 % ±0.49% ±0.66% ±0.86%
http/simple.js duration=5 chunkedEnc=1 c=500 chunks=4 len=102400 type='bytes' benchmarker='wrk' 0.10 % ±0.82% ±1.09% ±1.42%
http/simple.js duration=5 chunkedEnc=1 c=500 chunks=4 len=4 type='buffer' benchmarker='wrk' 0.35 % ±0.74% ±0.98% ±1.28%
http/simple.js duration=5 chunkedEnc=1 c=500 chunks=4 len=4 type='bytes' benchmarker='wrk' -0.26 % ±0.65% ±0.86% ±1.12%
http/upgrade.js n=1000 0.73 % ±2.37% ±3.16% ±4.11%
http/upgrade.js n=5 6.72 % ±8.30% ±11.05% ±14.38%

Be aware that when doing many comparisons the risk of a false-positive result increases.

In this case, there are 235 comparisons, you can thus expect the following amount of false-positive results:

11.75 false positives, when considering a 5% risk acceptance (*, **, *),

2.35 false positives, when considering a 1% risk acceptance (, ),

0.24 false positives, when considering a 0.1% risk acceptance ()
Looks good I think. Headlines:
  • No notable regressions - each of the small negative cases I can see are low-confidence and fit into an overall pattern of no change considering the tests around them
  • A very consistent 9.59% - 9.87% speed up in http/set-header.js test, which tests headers + res.end(body).
  • For http/simple:

    • Consistent boost around 9.5% with type=bytes, no chunking, and len up to 1024.
    • 3% boost with type=buffer, on the same small non-chunked responses.
    • Both buffer & byte body perf dropping to about 1-2% improvement for larger bodies (1MB).
    • No significant change with chunked encoding.
  • 10.48% boost to http/end-string test with 1KB, dropping to 5.59% with 16KB, down to 2.47% improvement with 1MB.
  • ~2% boost across various http/end-vs-write-end.js cases that call end(data) on different large sizes.
Looks pretty convincing to me! All approved and ready-to-go now and I think this is all just good news, so I'll commit-queue.
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@pimterry@aduh95
http: improve performance with known-length calls to end()
89ac179
This boosts RPS performance for the common API case where you call
`res.end(data)` with the entire response by up to 9%.
Signed-off-by: Tim Perry <pimterry@gmail.com>
PR-URL: #65466
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
Reviewed-By: Yagiz Nizipli <yagiz@nizipli.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Gürgün Dayıoğlu <hey@gurgun.day>
aduh95 pushed a commit
that referenced
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Aug 25, 2026
@pimterry@aduh95
http: improve performance with known-length calls to end()
c2c31d6
This boosts RPS performance for the common API case where you call
`res.end(data)` with the entire response by up to 9%.
Signed-off-by: Tim Perry <pimterry@gmail.com>
PR-URL: #65466
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
Reviewed-By: Yagiz Nizipli <yagiz@nizipli.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Gürgün Dayıoğlu <hey@gurgun.day>
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aduh95 pushed a commit
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Aug 27, 2026
@pimterry@aduh95
http: improve performance with known-length calls to end()
5b13d30
This boosts RPS performance for the common API case where you call
`res.end(data)` with the entire response by up to 9%.
Signed-off-by: Tim Perry <pimterry@gmail.com>
PR-URL: #65466
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
Reviewed-By: Yagiz Nizipli <yagiz@nizipli.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Gürgün Dayıoğlu <hey@gurgun.day>
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@mcollinamcollinamcollina approved these changes
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