WIP: Perf test always using the parallel-rustc code path

[oli-obk]

No description provided.

[rustbot]

Thanks for the pull request, and welcome! The Rust team is excited to review your changes, and you should hear from @eholk (or someone else) soon.

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[oli-obk]

@bors try @rust-timer queue

[bors]

⌛ Trying commit b6fc18a with merge ef19a9ab460411352fe72081f5f6c6bbfe25a004...

[bors]

☀️ Try build successful - checks-actions
Build commit: ef19a9ab460411352fe72081f5f6c6bbfe25a004 (ef19a9ab460411352fe72081f5f6c6bbfe25a004)

[rust-timer]

Finished benchmarking commit (ef19a9ab460411352fe72081f5f6c6bbfe25a004): comparison URL.

Overall result: ❌ regressions - ACTION NEEDED

Benchmarking this pull request likely means that it is perf-sensitive, so we're automatically marking it as not fit for rolling up. While you can manually mark this PR as fit for rollup, we strongly recommend not doing so since this PR may lead to changes in compiler perf.

Next Steps: If you can justify the regressions found in this try perf run, please indicate this with @rustbot label: +perf-regression-triaged along with sufficient written justification. If you cannot justify the regressions please fix the regressions and do another perf run. If the next run shows neutral or positive results, the label will be automatically removed.

@bors rollup=never
@rustbot label: -S-waiting-on-perf +perf-regression

Instruction count

This is a highly reliable metric that was used to determine the overall result at the top of this comment.

	mean	range	count
Regressions ❌ (primary)	-	-	0
Regressions ❌ (secondary)	5.7%	[5.7%, 5.7%]	1
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	-	-	0

Max RSS (memory usage)

Results

This is a less reliable metric that may be of interest but was not used to determine the overall result at the top of this comment.

	mean	range	count
Regressions ❌ (primary)	2.3%	[2.3%, 2.3%]	1
Regressions ❌ (secondary)	2.2%	[1.2%, 2.9%]	3
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-3.9%	[-4.2%, -3.6%]	2
All ❌✅ (primary)	2.3%	[2.3%, 2.3%]	1

Cycles

This benchmark run did not return any relevant results for this metric.

Binary size

This benchmark run did not return any relevant results for this metric.

Bootstrap: 652.303s -> 652.472s (0.03%)

[oli-obk]

Going with #114283 instead