Implement ZStandard Stream, Encoder, Decoder - #119575

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rzikm:59591-zstd
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Implement ZStandard Stream, Encoder, Decoder#119575
rzikm merged 130 commits into
dotnet:mainfrom
rzikm:59591-zstd

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Implements #59591

There are some patches applied to vendored zstd sources which are listed in src/native/zstd-version.txt, neither of them should be necessary once we update to next release (maintainers didn't commit to a release date, but hopefully they will release something early next year).

Benchmarks results (taken from dotnet/performance repo) look great so far

Benchmark results
MethodlevelfileAlgorithmMeanErrorStdDevSizeCompressed
CompressOptimalalice29.txtBrotli2,306.40 μs45.807 μs71.316 μs14848154517
CompressOptimalalice29.txtZstandard842.743 μs8.3719 μs7.8310 μs14848154919
CompressOptimalalice29.txtDeflate2,421.16 μs41.274 μs38.608 μs14848153890
DecompressOptimalalice29.txtBrotli320.82 μs4.802 μs4.257 μs
DecompressOptimalalice29.txtZstandard139.251 μs2.0885 μs1.7440 μs
DecompressOptimalalice29.txtDeflate275.43 μs4.849 μs4.535 μs
CompressOptimalsumBrotli577.62 μs7.647 μs5.971 μs3824012527
CompressOptimalsumZstandard155.050 μs3.0367 μs3.3753 μs3824013389
CompressOptimalsumDeflate404.70 μs7.732 μs9.779 μs3824013388
DecompressOptimalsumBrotli101.26 μs2.781 μs7.566 μs
DecompressOptimalsumZstandard31.333 μs0.6172 μs0.5774 μs
DecompressOptimalsumDeflate54.86 μs0.676 μs0.632 μs
CompressOptimalTestDocument.pdfBrotli763.43 μs13.851 μs23.520 μs121993115863
CompressOptimalTestDocument.pdfZstandard182.115 μs3.3456 μs2.9658 μs121993119285
CompressOptimalTestDocument.pdfDeflate2,133.16 μs42.543 μs104.358 μs121993115369
DecompressOptimalTestDocument.pdfBrotli267.64 μs5.281 μs10.047 μs
DecompressOptimalTestDocument.pdfZstandard17.508 μs0.3336 μs0.3708 μs
DecompressOptimalTestDocument.pdfDeflate224.92 μs2.642 μs2.342 μs
CompressFastestalice29.txtBrotli732.30 μs14.288 μs19.074 μs14848159265
CompressFastestalice29.txtZstandard509.3 us5.10 us4.53 us14848159891
CompressFastestalice29.txtDeflate612.28 μs11.300 μs16.564 μs14848183053
DecompressFastestalice29.txtBrotli380.92 μs7.570 μs9.844 μs
DecompressFastestalice29.txtZstandard111.14 us1.321 us1.103 us
DecompressFastestalice29.txtDeflate361.78 μs6.700 μs14.847 μs
CompressFastestsumBrotli125.26 μs2.489 μs3.801 μs3824014305
CompressFastestsumZstandard108.0 us1.05 us0.88 us3824013848
CompressFastestsumDeflate121.81 μs2.409 μs4.699 μs3824017222
DecompressFastestsumBrotli99.19 μs1.974 μs3.243 μs
DecompressFastestsumZstandard29.01 us0.559 us0.599 us
DecompressFastestsumDeflate58.68 μs0.999 μs0.934 μs
CompressFastestTestDocument.pdfBrotli300.40 μs5.753 μs6.394 μs121993117104
CompressFastestTestDocument.pdfZstandard137.3 us2.00 us1.67 us121993119405
CompressFastestTestDocument.pdfDeflate947.61 μs17.861 μs18.342 μs121993121404
DecompressFastestTestDocument.pdfBrotli233.14 μs3.625 μs3.391 μs
DecompressFastestTestDocument.pdfZstandard17.22 us0.260 us0.244 us
DecompressFastestTestDocument.pdfDeflate238.81 μs2.153 μs1.908 μs

Supported platforms (verified by CI): Windows, Linux, OSX, Mobile

  • WASM support should be possible, but will need a bit of work to make it opt-in to avoid increasing the runtime size. Will be left for follow-up.

Binary size diff (local debug build, Windows, main vs PR):

NameBeforeAfterDiff
System.IO.Compression.Native.dll4 861 9526 029 8241 167 872
System.IO.Compression.Zstandard.dll054 78454 784

we can probably shave off about 130 kB by removing legacy support (support for formats used by previous zstd versions, see https://deepwiki.com/facebook/zstd/15-legacy-support), but I am not sure if that is worth it.

I wasnt able to check trimmed size of a single-file application, but I expect that roughly +1.1 MB increase due to lack of native pruning capabilities.

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Pull Request Overview

This PR implements ZStandard stream, encoder, and decoder functionality for .NET by integrating the zstd native library. The changes primarily consist of adding the external zstd library source files and build infrastructure to support compression and decompression capabilities.

Key Changes:

  • Integration of zstd native library source code (version metadata suggests 0.9.0)
  • Build system configuration files for Meson and CMake
  • Single-file library generation scripts and examples
  • Test infrastructure for the zstd implementation

Reviewed Changes

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FileDescription
src/native/external/zstd/lib/common/fse_decompress.cFSE (Finite State Entropy) decompression implementation
src/native/external/zstd/lib/common/fse.hFSE codec public API and data structures
src/native/external/zstd/lib/common/error_private.hInternal error handling macros and definitions
src/native/external/zstd/lib/common/error_private.cError code to string mapping implementation
src/native/external/zstd/lib/common/entropy_common.cCommon entropy encoding/decoding functions
src/native/external/zstd/lib/common/debug.hDebug logging and assertion macros
src/native/external/zstd/lib/common/debug.cDebug level global variable definition
src/native/external/zstd/lib/common/cpu.hCPU feature detection (BMI2, AVX, etc.)
src/native/external/zstd/lib/common/compiler.hCompiler-specific macros and attributes
src/native/external/zstd/lib/common/bitstream.hBitstream encoding/decoding utilities
src/native/external/zstd/lib/common/bits.hBit manipulation helper functions
src/native/external/zstd/lib/common/allocations.hCustom memory allocation wrappers
src/native/external/zstd/lib/README.mdDocumentation for library structure and build options
src/native/external/zstd/lib/MakefileBuild configuration for the zstd library
src/native/external/zstd/lib/BUCKBuck build system configuration
src/native/external/zstd/lib/.gitignoreGit ignore rules for build artifacts
src/native/external/zstd/build/single_file_libs/*Scripts and examples for single-file library generation
src/native/external/zstd/build/meson/*Meson build system configuration files
src/native/external/zstd/build/cmake/tests/.gitignoreGit ignore rules for CMake test artifacts

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I think this PR is ready for the first round of reviews

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/azp run runtime-extra-platforms

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/ba-g Test failures are unrelated

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Pull request overview

Copilot reviewed 46 out of 46 changed files in this pull request and generated no new comments.

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/azp run runtime-extra-platforms

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/azp run runtime-extra-platforms

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@gewarren Could you please take a look at the documentation comments if it is consistent with what we generally write?

CC also @blowdart@GrabYourPitchforks who also wanted to look at the comments.

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/azp run runtime-extra-platforms

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@rzikm I left some suggestions, thanks for tagging me.

Comment threadsrc/libraries/System.IO.Compression.Zstandard/src/Resources/Strings.resx Outdated
Comment thread...ies/System.IO.Compression.Zstandard/src/System/IO/Compression/ZstandardCompressionOptions.cs Outdated
Comment thread...ies/System.IO.Compression.Zstandard/src/System/IO/Compression/ZstandardCompressionOptions.cs Outdated
Comment thread...ies/System.IO.Compression.Zstandard/src/System/IO/Compression/ZstandardCompressionOptions.cs Outdated
Comment thread...ies/System.IO.Compression.Zstandard/src/System/IO/Compression/ZstandardCompressionOptions.cs Outdated
Comment threadsrc/libraries/System.IO.Compression.Zstandard/src/System/IO/Compression/ZstandardEncoder.cs Outdated
Comment threadsrc/libraries/System.IO.Compression.Zstandard/src/System/IO/Compression/ZstandardStream.cs Outdated
Comment threadsrc/libraries/System.IO.Compression.Zstandard/src/System/IO/Compression/ZstandardStream.cs Outdated
Comment threadsrc/libraries/System.IO.Compression.Zstandard/src/System/IO/Compression/ZstandardStream.cs Outdated
Comment threadsrc/libraries/System.IO.Compression.Zstandard/src/System/IO/Compression/ZstandardStream.cs Outdated
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Fix some documentation wording
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More docs improvements
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Revert "fixup! fixup! Enable on WASI/Browser"
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This reverts commit c0917ab.
Revert "fixup! Enable on WASI/Browser"
This reverts commit 2a5e1db.
Revert "Enable on WASI/Browser"
This reverts commit 6013b24.
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Implement ZStandard Stream, Encoder, Decoder - #119575
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rzikm merged 130 commits into
dotnet:mainfrom 
rzikm:59591-zstd
Jan 22, 2026
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Implement ZStandard Stream, Encoder, Decoder#119575
rzikm merged 130 commits into
dotnet:mainfrom 
rzikm:59591-zstd
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Implements #59591
There are some patches applied to vendored zstd sources which are listed in src/native/zstd-version.txt, neither of them should be necessary once we update to next release (maintainers didn't commit to a release date, but hopefully they will release something early next year).
Benchmarks results (taken from dotnet/performance repo) look great so far
 Benchmark results
MethodlevelfileAlgorithmMeanErrorStdDevSizeCompressed
CompressOptimalalice29.txtBrotli2,306.40 μs45.807 μs71.316 μs14848154517
CompressOptimalalice29.txtZstandard842.743 μs8.3719 μs7.8310 μs14848154919
CompressOptimalalice29.txtDeflate2,421.16 μs41.274 μs38.608 μs14848153890
DecompressOptimalalice29.txtBrotli320.82 μs4.802 μs4.257 μs
DecompressOptimalalice29.txtZstandard139.251 μs2.0885 μs1.7440 μs
DecompressOptimalalice29.txtDeflate275.43 μs4.849 μs4.535 μs
CompressOptimalsumBrotli577.62 μs7.647 μs5.971 μs3824012527
CompressOptimalsumZstandard155.050 μs3.0367 μs3.3753 μs3824013389
CompressOptimalsumDeflate404.70 μs7.732 μs9.779 μs3824013388
DecompressOptimalsumBrotli101.26 μs2.781 μs7.566 μs
DecompressOptimalsumZstandard31.333 μs0.6172 μs0.5774 μs
DecompressOptimalsumDeflate54.86 μs0.676 μs0.632 μs
CompressOptimalTestDocument.pdfBrotli763.43 μs13.851 μs23.520 μs121993115863
CompressOptimalTestDocument.pdfZstandard182.115 μs3.3456 μs2.9658 μs121993119285
CompressOptimalTestDocument.pdfDeflate2,133.16 μs42.543 μs104.358 μs121993115369
DecompressOptimalTestDocument.pdfBrotli267.64 μs5.281 μs10.047 μs
DecompressOptimalTestDocument.pdfZstandard17.508 μs0.3336 μs0.3708 μs
DecompressOptimalTestDocument.pdfDeflate224.92 μs2.642 μs2.342 μs
CompressFastestalice29.txtBrotli732.30 μs14.288 μs19.074 μs14848159265
CompressFastestalice29.txtZstandard509.3 us5.10 us4.53 us14848159891
CompressFastestalice29.txtDeflate612.28 μs11.300 μs16.564 μs14848183053
DecompressFastestalice29.txtBrotli380.92 μs7.570 μs9.844 μs
DecompressFastestalice29.txtZstandard111.14 us1.321 us1.103 us
DecompressFastestalice29.txtDeflate361.78 μs6.700 μs14.847 μs
CompressFastestsumBrotli125.26 μs2.489 μs3.801 μs3824014305
CompressFastestsumZstandard108.0 us1.05 us0.88 us3824013848
CompressFastestsumDeflate121.81 μs2.409 μs4.699 μs3824017222
DecompressFastestsumBrotli99.19 μs1.974 μs3.243 μs
DecompressFastestsumZstandard29.01 us0.559 us0.599 us
DecompressFastestsumDeflate58.68 μs0.999 μs0.934 μs
CompressFastestTestDocument.pdfBrotli300.40 μs5.753 μs6.394 μs121993117104
CompressFastestTestDocument.pdfZstandard137.3 us2.00 us1.67 us121993119405
CompressFastestTestDocument.pdfDeflate947.61 μs17.861 μs18.342 μs121993121404
DecompressFastestTestDocument.pdfBrotli233.14 μs3.625 μs3.391 μs
DecompressFastestTestDocument.pdfZstandard17.22 us0.260 us0.244 us
DecompressFastestTestDocument.pdfDeflate238.81 μs2.153 μs1.908 μs
Supported platforms (verified by CI): Windows, Linux, OSX, Mobile
  • WASM support should be possible, but will need a bit of work to make it opt-in to avoid increasing the runtime size. Will be left for follow-up.
Binary size diff (local debug build, Windows, main vs PR):
NameBeforeAfterDiff
System.IO.Compression.Native.dll4 861 9526 029 8241 167 872
System.IO.Compression.Zstandard.dll054 78454 784
we can probably shave off about 130 kB by removing legacy support (support for formats used by previous zstd versions, see https://deepwiki.com/facebook/zstd/15-legacy-support), but I am not sure if that is worth it.
I wasnt able to check trimmed size of a single-file application, but I expect that roughly +1.1 MB increase due to lack of native pruning capabilities.
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Pull Request Overview
This PR implements ZStandard stream, encoder, and decoder functionality for .NET by integrating the zstd native library. The changes primarily consist of adding the external zstd library source files and build infrastructure to support compression and decompression capabilities.
Key Changes:
  • Integration of zstd native library source code (version metadata suggests 0.9.0)
  • Build system configuration files for Meson and CMake
  • Single-file library generation scripts and examples
  • Test infrastructure for the zstd implementation
Reviewed Changes
Copilot reviewed 142 out of 237 changed files in this pull request and generated no comments.
Show a summary per file
FileDescription
src/native/external/zstd/lib/common/fse_decompress.cFSE (Finite State Entropy) decompression implementation
src/native/external/zstd/lib/common/fse.hFSE codec public API and data structures
src/native/external/zstd/lib/common/error_private.hInternal error handling macros and definitions
src/native/external/zstd/lib/common/error_private.cError code to string mapping implementation
src/native/external/zstd/lib/common/entropy_common.cCommon entropy encoding/decoding functions
src/native/external/zstd/lib/common/debug.hDebug logging and assertion macros
src/native/external/zstd/lib/common/debug.cDebug level global variable definition
src/native/external/zstd/lib/common/cpu.hCPU feature detection (BMI2, AVX, etc.)
src/native/external/zstd/lib/common/compiler.hCompiler-specific macros and attributes
src/native/external/zstd/lib/common/bitstream.hBitstream encoding/decoding utilities
src/native/external/zstd/lib/common/bits.hBit manipulation helper functions
src/native/external/zstd/lib/common/allocations.hCustom memory allocation wrappers
src/native/external/zstd/lib/README.mdDocumentation for library structure and build options
src/native/external/zstd/lib/MakefileBuild configuration for the zstd library
src/native/external/zstd/lib/BUCKBuck build system configuration
src/native/external/zstd/lib/.gitignoreGit ignore rules for build artifacts
src/native/external/zstd/build/single_file_libs/*Scripts and examples for single-file library generation
src/native/external/zstd/build/meson/*Meson build system configuration files
src/native/external/zstd/build/cmake/tests/.gitignoreGit ignore rules for CMake test artifacts
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I think this PR is ready for the first round of reviews
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/azp run runtime-extra-platforms
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/ba-g Test failures are unrelated
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Pull request overview
Copilot reviewed 46 out of 46 changed files in this pull request and generated no new comments.
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/azp run runtime-extra-platforms
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/azp run runtime-extra-platforms
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@gewarren Could you please take a look at the documentation comments if it is consistent with what we generally write?
CC also @blowdart@GrabYourPitchforks who also wanted to look at the comments.
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/azp run runtime-extra-platforms
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@rzikm I left some suggestions, thanks for tagging me.
Comment threadsrc/libraries/System.IO.Compression.Zstandard/src/Resources/Strings.resx
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Comment thread...ies/System.IO.Compression.Zstandard/src/System/IO/Compression/ZstandardCompressionOptions.cs
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Comment thread...ies/System.IO.Compression.Zstandard/src/System/IO/Compression/ZstandardCompressionOptions.cs
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Comment thread...ies/System.IO.Compression.Zstandard/src/System/IO/Compression/ZstandardCompressionOptions.cs
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Comment thread...ies/System.IO.Compression.Zstandard/src/System/IO/Compression/ZstandardCompressionOptions.cs
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Comment threadsrc/libraries/System.IO.Compression.Zstandard/src/System/IO/Compression/ZstandardEncoder.cs
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Comment threadsrc/libraries/System.IO.Compression.Zstandard/src/System/IO/Compression/ZstandardStream.cs
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Comment threadsrc/libraries/System.IO.Compression.Zstandard/src/System/IO/Compression/ZstandardStream.cs
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Comment threadsrc/libraries/System.IO.Compression.Zstandard/src/System/IO/Compression/ZstandardStream.cs
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Comment threadsrc/libraries/System.IO.Compression.Zstandard/src/System/IO/Compression/ZstandardStream.cs
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Fix some documentation wording
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Revert "fixup! fixup! Enable on WASI/Browser"
196fbc9
This reverts commit c0917ab.
Revert "fixup! Enable on WASI/Browser"
This reverts commit 2a5e1db.
Revert "Enable on WASI/Browser"
This reverts commit 6013b24.
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Implement ZStandard Stream, Encoder, Decoder - #119575
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rzikm:59591-zstd
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Implement ZStandard Stream, Encoder, Decoder#119575
rzikm merged 130 commits into
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rzikm:59591-zstd
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Implements #59591
There are some patches applied to vendored zstd sources which are listed in src/native/zstd-version.txt, neither of them should be necessary once we update to next release (maintainers didn't commit to a release date, but hopefully they will release something early next year).
Benchmarks results (taken from dotnet/performance repo) look great so far
 Benchmark results
MethodlevelfileAlgorithmMeanErrorStdDevSizeCompressed
CompressOptimalalice29.txtBrotli2,306.40 μs45.807 μs71.316 μs14848154517
CompressOptimalalice29.txtZstandard842.743 μs8.3719 μs7.8310 μs14848154919
CompressOptimalalice29.txtDeflate2,421.16 μs41.274 μs38.608 μs14848153890
DecompressOptimalalice29.txtBrotli320.82 μs4.802 μs4.257 μs
DecompressOptimalalice29.txtZstandard139.251 μs2.0885 μs1.7440 μs
DecompressOptimalalice29.txtDeflate275.43 μs4.849 μs4.535 μs
CompressOptimalsumBrotli577.62 μs7.647 μs5.971 μs3824012527
CompressOptimalsumZstandard155.050 μs3.0367 μs3.3753 μs3824013389
CompressOptimalsumDeflate404.70 μs7.732 μs9.779 μs3824013388
DecompressOptimalsumBrotli101.26 μs2.781 μs7.566 μs
DecompressOptimalsumZstandard31.333 μs0.6172 μs0.5774 μs
DecompressOptimalsumDeflate54.86 μs0.676 μs0.632 μs
CompressOptimalTestDocument.pdfBrotli763.43 μs13.851 μs23.520 μs121993115863
CompressOptimalTestDocument.pdfZstandard182.115 μs3.3456 μs2.9658 μs121993119285
CompressOptimalTestDocument.pdfDeflate2,133.16 μs42.543 μs104.358 μs121993115369
DecompressOptimalTestDocument.pdfBrotli267.64 μs5.281 μs10.047 μs
DecompressOptimalTestDocument.pdfZstandard17.508 μs0.3336 μs0.3708 μs
DecompressOptimalTestDocument.pdfDeflate224.92 μs2.642 μs2.342 μs
CompressFastestalice29.txtBrotli732.30 μs14.288 μs19.074 μs14848159265
CompressFastestalice29.txtZstandard509.3 us5.10 us4.53 us14848159891
CompressFastestalice29.txtDeflate612.28 μs11.300 μs16.564 μs14848183053
DecompressFastestalice29.txtBrotli380.92 μs7.570 μs9.844 μs
DecompressFastestalice29.txtZstandard111.14 us1.321 us1.103 us
DecompressFastestalice29.txtDeflate361.78 μs6.700 μs14.847 μs
CompressFastestsumBrotli125.26 μs2.489 μs3.801 μs3824014305
CompressFastestsumZstandard108.0 us1.05 us0.88 us3824013848
CompressFastestsumDeflate121.81 μs2.409 μs4.699 μs3824017222
DecompressFastestsumBrotli99.19 μs1.974 μs3.243 μs
DecompressFastestsumZstandard29.01 us0.559 us0.599 us
DecompressFastestsumDeflate58.68 μs0.999 μs0.934 μs
CompressFastestTestDocument.pdfBrotli300.40 μs5.753 μs6.394 μs121993117104
CompressFastestTestDocument.pdfZstandard137.3 us2.00 us1.67 us121993119405
CompressFastestTestDocument.pdfDeflate947.61 μs17.861 μs18.342 μs121993121404
DecompressFastestTestDocument.pdfBrotli233.14 μs3.625 μs3.391 μs
DecompressFastestTestDocument.pdfZstandard17.22 us0.260 us0.244 us
DecompressFastestTestDocument.pdfDeflate238.81 μs2.153 μs1.908 μs
Supported platforms (verified by CI): Windows, Linux, OSX, Mobile
  • WASM support should be possible, but will need a bit of work to make it opt-in to avoid increasing the runtime size. Will be left for follow-up.
Binary size diff (local debug build, Windows, main vs PR):
NameBeforeAfterDiff
System.IO.Compression.Native.dll4 861 9526 029 8241 167 872
System.IO.Compression.Zstandard.dll054 78454 784
we can probably shave off about 130 kB by removing legacy support (support for formats used by previous zstd versions, see https://deepwiki.com/facebook/zstd/15-legacy-support), but I am not sure if that is worth it.
I wasnt able to check trimmed size of a single-file application, but I expect that roughly +1.1 MB increase due to lack of native pruning capabilities.
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Pull Request Overview
This PR implements ZStandard stream, encoder, and decoder functionality for .NET by integrating the zstd native library. The changes primarily consist of adding the external zstd library source files and build infrastructure to support compression and decompression capabilities.
Key Changes:
  • Integration of zstd native library source code (version metadata suggests 0.9.0)
  • Build system configuration files for Meson and CMake
  • Single-file library generation scripts and examples
  • Test infrastructure for the zstd implementation
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FileDescription
src/native/external/zstd/lib/common/fse_decompress.cFSE (Finite State Entropy) decompression implementation
src/native/external/zstd/lib/common/fse.hFSE codec public API and data structures
src/native/external/zstd/lib/common/error_private.hInternal error handling macros and definitions
src/native/external/zstd/lib/common/error_private.cError code to string mapping implementation
src/native/external/zstd/lib/common/entropy_common.cCommon entropy encoding/decoding functions
src/native/external/zstd/lib/common/debug.hDebug logging and assertion macros
src/native/external/zstd/lib/common/debug.cDebug level global variable definition
src/native/external/zstd/lib/common/cpu.hCPU feature detection (BMI2, AVX, etc.)
src/native/external/zstd/lib/common/compiler.hCompiler-specific macros and attributes
src/native/external/zstd/lib/common/bitstream.hBitstream encoding/decoding utilities
src/native/external/zstd/lib/common/bits.hBit manipulation helper functions
src/native/external/zstd/lib/common/allocations.hCustom memory allocation wrappers
src/native/external/zstd/lib/README.mdDocumentation for library structure and build options
src/native/external/zstd/lib/MakefileBuild configuration for the zstd library
src/native/external/zstd/lib/BUCKBuck build system configuration
src/native/external/zstd/lib/.gitignoreGit ignore rules for build artifacts
src/native/external/zstd/build/single_file_libs/*Scripts and examples for single-file library generation
src/native/external/zstd/build/meson/*Meson build system configuration files
src/native/external/zstd/build/cmake/tests/.gitignoreGit ignore rules for CMake test artifacts
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I think this PR is ready for the first round of reviews
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/azp run runtime-extra-platforms
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/ba-g Test failures are unrelated
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Pull request overview
Copilot reviewed 46 out of 46 changed files in this pull request and generated no new comments.
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/azp run runtime-extra-platforms
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/azp run runtime-extra-platforms
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@gewarren Could you please take a look at the documentation comments if it is consistent with what we generally write?
CC also @blowdart@GrabYourPitchforks who also wanted to look at the comments.
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/azp run runtime-extra-platforms
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@rzikm I left some suggestions, thanks for tagging me.
Comment threadsrc/libraries/System.IO.Compression.Zstandard/src/Resources/Strings.resx
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Comment thread...ies/System.IO.Compression.Zstandard/src/System/IO/Compression/ZstandardCompressionOptions.cs
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Comment thread...ies/System.IO.Compression.Zstandard/src/System/IO/Compression/ZstandardCompressionOptions.cs
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Comment thread...ies/System.IO.Compression.Zstandard/src/System/IO/Compression/ZstandardCompressionOptions.cs
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Comment thread...ies/System.IO.Compression.Zstandard/src/System/IO/Compression/ZstandardCompressionOptions.cs
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Comment threadsrc/libraries/System.IO.Compression.Zstandard/src/System/IO/Compression/ZstandardEncoder.cs
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Comment threadsrc/libraries/System.IO.Compression.Zstandard/src/System/IO/Compression/ZstandardStream.cs
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Comment threadsrc/libraries/System.IO.Compression.Zstandard/src/System/IO/Compression/ZstandardStream.cs
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Comment threadsrc/libraries/System.IO.Compression.Zstandard/src/System/IO/Compression/ZstandardStream.cs
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Comment threadsrc/libraries/System.IO.Compression.Zstandard/src/System/IO/Compression/ZstandardStream.cs
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Fix some documentation wording
2be44ca
@rzikm
More docs improvements
c5f398a
@rzikm
Revert "fixup! fixup! Enable on WASI/Browser"
196fbc9
This reverts commit c0917ab.
Revert "fixup! Enable on WASI/Browser"
This reverts commit 2a5e1db.
Revert "Enable on WASI/Browser"
This reverts commit 6013b24.
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Implement ZStandard Stream, Encoder, Decoder - #119575
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rzikm merged 130 commits into
dotnet:mainfrom 
rzikm:59591-zstd
Jan 22, 2026
Merged
Implement ZStandard Stream, Encoder, Decoder#119575
rzikm merged 130 commits into
dotnet:mainfrom 
rzikm:59591-zstd
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Implements #59591
There are some patches applied to vendored zstd sources which are listed in src/native/zstd-version.txt, neither of them should be necessary once we update to next release (maintainers didn't commit to a release date, but hopefully they will release something early next year).
Benchmarks results (taken from dotnet/performance repo) look great so far
 Benchmark results
MethodlevelfileAlgorithmMeanErrorStdDevSizeCompressed
CompressOptimalalice29.txtBrotli2,306.40 μs45.807 μs71.316 μs14848154517
CompressOptimalalice29.txtZstandard842.743 μs8.3719 μs7.8310 μs14848154919
CompressOptimalalice29.txtDeflate2,421.16 μs41.274 μs38.608 μs14848153890
DecompressOptimalalice29.txtBrotli320.82 μs4.802 μs4.257 μs
DecompressOptimalalice29.txtZstandard139.251 μs2.0885 μs1.7440 μs
DecompressOptimalalice29.txtDeflate275.43 μs4.849 μs4.535 μs
CompressOptimalsumBrotli577.62 μs7.647 μs5.971 μs3824012527
CompressOptimalsumZstandard155.050 μs3.0367 μs3.3753 μs3824013389
CompressOptimalsumDeflate404.70 μs7.732 μs9.779 μs3824013388
DecompressOptimalsumBrotli101.26 μs2.781 μs7.566 μs
DecompressOptimalsumZstandard31.333 μs0.6172 μs0.5774 μs
DecompressOptimalsumDeflate54.86 μs0.676 μs0.632 μs
CompressOptimalTestDocument.pdfBrotli763.43 μs13.851 μs23.520 μs121993115863
CompressOptimalTestDocument.pdfZstandard182.115 μs3.3456 μs2.9658 μs121993119285
CompressOptimalTestDocument.pdfDeflate2,133.16 μs42.543 μs104.358 μs121993115369
DecompressOptimalTestDocument.pdfBrotli267.64 μs5.281 μs10.047 μs
DecompressOptimalTestDocument.pdfZstandard17.508 μs0.3336 μs0.3708 μs
DecompressOptimalTestDocument.pdfDeflate224.92 μs2.642 μs2.342 μs
CompressFastestalice29.txtBrotli732.30 μs14.288 μs19.074 μs14848159265
CompressFastestalice29.txtZstandard509.3 us5.10 us4.53 us14848159891
CompressFastestalice29.txtDeflate612.28 μs11.300 μs16.564 μs14848183053
DecompressFastestalice29.txtBrotli380.92 μs7.570 μs9.844 μs
DecompressFastestalice29.txtZstandard111.14 us1.321 us1.103 us
DecompressFastestalice29.txtDeflate361.78 μs6.700 μs14.847 μs
CompressFastestsumBrotli125.26 μs2.489 μs3.801 μs3824014305
CompressFastestsumZstandard108.0 us1.05 us0.88 us3824013848
CompressFastestsumDeflate121.81 μs2.409 μs4.699 μs3824017222
DecompressFastestsumBrotli99.19 μs1.974 μs3.243 μs
DecompressFastestsumZstandard29.01 us0.559 us0.599 us
DecompressFastestsumDeflate58.68 μs0.999 μs0.934 μs
CompressFastestTestDocument.pdfBrotli300.40 μs5.753 μs6.394 μs121993117104
CompressFastestTestDocument.pdfZstandard137.3 us2.00 us1.67 us121993119405
CompressFastestTestDocument.pdfDeflate947.61 μs17.861 μs18.342 μs121993121404
DecompressFastestTestDocument.pdfBrotli233.14 μs3.625 μs3.391 μs
DecompressFastestTestDocument.pdfZstandard17.22 us0.260 us0.244 us
DecompressFastestTestDocument.pdfDeflate238.81 μs2.153 μs1.908 μs
Supported platforms (verified by CI): Windows, Linux, OSX, Mobile
  • WASM support should be possible, but will need a bit of work to make it opt-in to avoid increasing the runtime size. Will be left for follow-up.
Binary size diff (local debug build, Windows, main vs PR):
NameBeforeAfterDiff
System.IO.Compression.Native.dll4 861 9526 029 8241 167 872
System.IO.Compression.Zstandard.dll054 78454 784
we can probably shave off about 130 kB by removing legacy support (support for formats used by previous zstd versions, see https://deepwiki.com/facebook/zstd/15-legacy-support), but I am not sure if that is worth it.
I wasnt able to check trimmed size of a single-file application, but I expect that roughly +1.1 MB increase due to lack of native pruning capabilities.
rzikm
rzikm
commented
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Pull Request Overview
This PR implements ZStandard stream, encoder, and decoder functionality for .NET by integrating the zstd native library. The changes primarily consist of adding the external zstd library source files and build infrastructure to support compression and decompression capabilities.
Key Changes:
  • Integration of zstd native library source code (version metadata suggests 0.9.0)
  • Build system configuration files for Meson and CMake
  • Single-file library generation scripts and examples
  • Test infrastructure for the zstd implementation
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FileDescription
src/native/external/zstd/lib/common/fse_decompress.cFSE (Finite State Entropy) decompression implementation
src/native/external/zstd/lib/common/fse.hFSE codec public API and data structures
src/native/external/zstd/lib/common/error_private.hInternal error handling macros and definitions
src/native/external/zstd/lib/common/error_private.cError code to string mapping implementation
src/native/external/zstd/lib/common/entropy_common.cCommon entropy encoding/decoding functions
src/native/external/zstd/lib/common/debug.hDebug logging and assertion macros
src/native/external/zstd/lib/common/debug.cDebug level global variable definition
src/native/external/zstd/lib/common/cpu.hCPU feature detection (BMI2, AVX, etc.)
src/native/external/zstd/lib/common/compiler.hCompiler-specific macros and attributes
src/native/external/zstd/lib/common/bitstream.hBitstream encoding/decoding utilities
src/native/external/zstd/lib/common/bits.hBit manipulation helper functions
src/native/external/zstd/lib/common/allocations.hCustom memory allocation wrappers
src/native/external/zstd/lib/README.mdDocumentation for library structure and build options
src/native/external/zstd/lib/MakefileBuild configuration for the zstd library
src/native/external/zstd/lib/BUCKBuck build system configuration
src/native/external/zstd/lib/.gitignoreGit ignore rules for build artifacts
src/native/external/zstd/build/single_file_libs/*Scripts and examples for single-file library generation
src/native/external/zstd/build/meson/*Meson build system configuration files
src/native/external/zstd/build/cmake/tests/.gitignoreGit ignore rules for CMake test artifacts
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I think this PR is ready for the first round of reviews
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/ba-g Test failures are unrelated
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Copilot reviewed 46 out of 46 changed files in this pull request and generated no new comments.
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@gewarren Could you please take a look at the documentation comments if it is consistent with what we generally write?
CC also @blowdart@GrabYourPitchforks who also wanted to look at the comments.
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@rzikm I left some suggestions, thanks for tagging me.
Comment threadsrc/libraries/System.IO.Compression.Zstandard/src/Resources/Strings.resx
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Comment thread...ies/System.IO.Compression.Zstandard/src/System/IO/Compression/ZstandardCompressionOptions.cs
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Comment threadsrc/libraries/System.IO.Compression.Zstandard/src/System/IO/Compression/ZstandardEncoder.cs
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Fix some documentation wording
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Revert "fixup! fixup! Enable on WASI/Browser"
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Revert "fixup! Enable on WASI/Browser"
This reverts commit 2a5e1db.
Revert "Enable on WASI/Browser"
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Implement ZStandard Stream, Encoder, Decoder - #119575
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rzikm:59591-zstd
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Implement ZStandard Stream, Encoder, Decoder#119575
rzikm merged 130 commits into
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rzikm:59591-zstd
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Implements #59591
There are some patches applied to vendored zstd sources which are listed in src/native/zstd-version.txt, neither of them should be necessary once we update to next release (maintainers didn't commit to a release date, but hopefully they will release something early next year).
Benchmarks results (taken from dotnet/performance repo) look great so far
 Benchmark results
MethodlevelfileAlgorithmMeanErrorStdDevSizeCompressed
CompressOptimalalice29.txtBrotli2,306.40 μs45.807 μs71.316 μs14848154517
CompressOptimalalice29.txtZstandard842.743 μs8.3719 μs7.8310 μs14848154919
CompressOptimalalice29.txtDeflate2,421.16 μs41.274 μs38.608 μs14848153890
DecompressOptimalalice29.txtBrotli320.82 μs4.802 μs4.257 μs
DecompressOptimalalice29.txtZstandard139.251 μs2.0885 μs1.7440 μs
DecompressOptimalalice29.txtDeflate275.43 μs4.849 μs4.535 μs
CompressOptimalsumBrotli577.62 μs7.647 μs5.971 μs3824012527
CompressOptimalsumZstandard155.050 μs3.0367 μs3.3753 μs3824013389
CompressOptimalsumDeflate404.70 μs7.732 μs9.779 μs3824013388
DecompressOptimalsumBrotli101.26 μs2.781 μs7.566 μs
DecompressOptimalsumZstandard31.333 μs0.6172 μs0.5774 μs
DecompressOptimalsumDeflate54.86 μs0.676 μs0.632 μs
CompressOptimalTestDocument.pdfBrotli763.43 μs13.851 μs23.520 μs121993115863
CompressOptimalTestDocument.pdfZstandard182.115 μs3.3456 μs2.9658 μs121993119285
CompressOptimalTestDocument.pdfDeflate2,133.16 μs42.543 μs104.358 μs121993115369
DecompressOptimalTestDocument.pdfBrotli267.64 μs5.281 μs10.047 μs
DecompressOptimalTestDocument.pdfZstandard17.508 μs0.3336 μs0.3708 μs
DecompressOptimalTestDocument.pdfDeflate224.92 μs2.642 μs2.342 μs
CompressFastestalice29.txtBrotli732.30 μs14.288 μs19.074 μs14848159265
CompressFastestalice29.txtZstandard509.3 us5.10 us4.53 us14848159891
CompressFastestalice29.txtDeflate612.28 μs11.300 μs16.564 μs14848183053
DecompressFastestalice29.txtBrotli380.92 μs7.570 μs9.844 μs
DecompressFastestalice29.txtZstandard111.14 us1.321 us1.103 us
DecompressFastestalice29.txtDeflate361.78 μs6.700 μs14.847 μs
CompressFastestsumBrotli125.26 μs2.489 μs3.801 μs3824014305
CompressFastestsumZstandard108.0 us1.05 us0.88 us3824013848
CompressFastestsumDeflate121.81 μs2.409 μs4.699 μs3824017222
DecompressFastestsumBrotli99.19 μs1.974 μs3.243 μs
DecompressFastestsumZstandard29.01 us0.559 us0.599 us
DecompressFastestsumDeflate58.68 μs0.999 μs0.934 μs
CompressFastestTestDocument.pdfBrotli300.40 μs5.753 μs6.394 μs121993117104
CompressFastestTestDocument.pdfZstandard137.3 us2.00 us1.67 us121993119405
CompressFastestTestDocument.pdfDeflate947.61 μs17.861 μs18.342 μs121993121404
DecompressFastestTestDocument.pdfBrotli233.14 μs3.625 μs3.391 μs
DecompressFastestTestDocument.pdfZstandard17.22 us0.260 us0.244 us
DecompressFastestTestDocument.pdfDeflate238.81 μs2.153 μs1.908 μs
Supported platforms (verified by CI): Windows, Linux, OSX, Mobile
  • WASM support should be possible, but will need a bit of work to make it opt-in to avoid increasing the runtime size. Will be left for follow-up.
Binary size diff (local debug build, Windows, main vs PR):
NameBeforeAfterDiff
System.IO.Compression.Native.dll4 861 9526 029 8241 167 872
System.IO.Compression.Zstandard.dll054 78454 784
we can probably shave off about 130 kB by removing legacy support (support for formats used by previous zstd versions, see https://deepwiki.com/facebook/zstd/15-legacy-support), but I am not sure if that is worth it.
I wasnt able to check trimmed size of a single-file application, but I expect that roughly +1.1 MB increase due to lack of native pruning capabilities.
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Pull Request Overview
This PR implements ZStandard stream, encoder, and decoder functionality for .NET by integrating the zstd native library. The changes primarily consist of adding the external zstd library source files and build infrastructure to support compression and decompression capabilities.
Key Changes:
  • Integration of zstd native library source code (version metadata suggests 0.9.0)
  • Build system configuration files for Meson and CMake
  • Single-file library generation scripts and examples
  • Test infrastructure for the zstd implementation
Reviewed Changes
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FileDescription
src/native/external/zstd/lib/common/fse_decompress.cFSE (Finite State Entropy) decompression implementation
src/native/external/zstd/lib/common/fse.hFSE codec public API and data structures
src/native/external/zstd/lib/common/error_private.hInternal error handling macros and definitions
src/native/external/zstd/lib/common/error_private.cError code to string mapping implementation
src/native/external/zstd/lib/common/entropy_common.cCommon entropy encoding/decoding functions
src/native/external/zstd/lib/common/debug.hDebug logging and assertion macros
src/native/external/zstd/lib/common/debug.cDebug level global variable definition
src/native/external/zstd/lib/common/cpu.hCPU feature detection (BMI2, AVX, etc.)
src/native/external/zstd/lib/common/compiler.hCompiler-specific macros and attributes
src/native/external/zstd/lib/common/bitstream.hBitstream encoding/decoding utilities
src/native/external/zstd/lib/common/bits.hBit manipulation helper functions
src/native/external/zstd/lib/common/allocations.hCustom memory allocation wrappers
src/native/external/zstd/lib/README.mdDocumentation for library structure and build options
src/native/external/zstd/lib/MakefileBuild configuration for the zstd library
src/native/external/zstd/lib/BUCKBuck build system configuration
src/native/external/zstd/lib/.gitignoreGit ignore rules for build artifacts
src/native/external/zstd/build/single_file_libs/*Scripts and examples for single-file library generation
src/native/external/zstd/build/meson/*Meson build system configuration files
src/native/external/zstd/build/cmake/tests/.gitignoreGit ignore rules for CMake test artifacts
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I think this PR is ready for the first round of reviews
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/ba-g Test failures are unrelated
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Copilot reviewed 46 out of 46 changed files in this pull request and generated no new comments.
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@gewarren Could you please take a look at the documentation comments if it is consistent with what we generally write?
CC also @blowdart@GrabYourPitchforks who also wanted to look at the comments.
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@rzikm I left some suggestions, thanks for tagging me.
Comment threadsrc/libraries/System.IO.Compression.Zstandard/src/Resources/Strings.resx
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Comment thread...ies/System.IO.Compression.Zstandard/src/System/IO/Compression/ZstandardCompressionOptions.cs
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Comment threadsrc/libraries/System.IO.Compression.Zstandard/src/System/IO/Compression/ZstandardEncoder.cs
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Fix some documentation wording
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Revert "fixup! fixup! Enable on WASI/Browser"
196fbc9
This reverts commit c0917ab.
Revert "fixup! Enable on WASI/Browser"
This reverts commit 2a5e1db.
Revert "Enable on WASI/Browser"
This reverts commit 6013b24.
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Implement ZStandard Stream, Encoder, Decoder - #119575
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rzikm:59591-zstd
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Implement ZStandard Stream, Encoder, Decoder#119575
rzikm merged 130 commits into
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rzikm:59591-zstd
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Implements #59591
There are some patches applied to vendored zstd sources which are listed in src/native/zstd-version.txt, neither of them should be necessary once we update to next release (maintainers didn't commit to a release date, but hopefully they will release something early next year).
Benchmarks results (taken from dotnet/performance repo) look great so far
 Benchmark results
MethodlevelfileAlgorithmMeanErrorStdDevSizeCompressed
CompressOptimalalice29.txtBrotli2,306.40 μs45.807 μs71.316 μs14848154517
CompressOptimalalice29.txtZstandard842.743 μs8.3719 μs7.8310 μs14848154919
CompressOptimalalice29.txtDeflate2,421.16 μs41.274 μs38.608 μs14848153890
DecompressOptimalalice29.txtBrotli320.82 μs4.802 μs4.257 μs
DecompressOptimalalice29.txtZstandard139.251 μs2.0885 μs1.7440 μs
DecompressOptimalalice29.txtDeflate275.43 μs4.849 μs4.535 μs
CompressOptimalsumBrotli577.62 μs7.647 μs5.971 μs3824012527
CompressOptimalsumZstandard155.050 μs3.0367 μs3.3753 μs3824013389
CompressOptimalsumDeflate404.70 μs7.732 μs9.779 μs3824013388
DecompressOptimalsumBrotli101.26 μs2.781 μs7.566 μs
DecompressOptimalsumZstandard31.333 μs0.6172 μs0.5774 μs
DecompressOptimalsumDeflate54.86 μs0.676 μs0.632 μs
CompressOptimalTestDocument.pdfBrotli763.43 μs13.851 μs23.520 μs121993115863
CompressOptimalTestDocument.pdfZstandard182.115 μs3.3456 μs2.9658 μs121993119285
CompressOptimalTestDocument.pdfDeflate2,133.16 μs42.543 μs104.358 μs121993115369
DecompressOptimalTestDocument.pdfBrotli267.64 μs5.281 μs10.047 μs
DecompressOptimalTestDocument.pdfZstandard17.508 μs0.3336 μs0.3708 μs
DecompressOptimalTestDocument.pdfDeflate224.92 μs2.642 μs2.342 μs
CompressFastestalice29.txtBrotli732.30 μs14.288 μs19.074 μs14848159265
CompressFastestalice29.txtZstandard509.3 us5.10 us4.53 us14848159891
CompressFastestalice29.txtDeflate612.28 μs11.300 μs16.564 μs14848183053
DecompressFastestalice29.txtBrotli380.92 μs7.570 μs9.844 μs
DecompressFastestalice29.txtZstandard111.14 us1.321 us1.103 us
DecompressFastestalice29.txtDeflate361.78 μs6.700 μs14.847 μs
CompressFastestsumBrotli125.26 μs2.489 μs3.801 μs3824014305
CompressFastestsumZstandard108.0 us1.05 us0.88 us3824013848
CompressFastestsumDeflate121.81 μs2.409 μs4.699 μs3824017222
DecompressFastestsumBrotli99.19 μs1.974 μs3.243 μs
DecompressFastestsumZstandard29.01 us0.559 us0.599 us
DecompressFastestsumDeflate58.68 μs0.999 μs0.934 μs
CompressFastestTestDocument.pdfBrotli300.40 μs5.753 μs6.394 μs121993117104
CompressFastestTestDocument.pdfZstandard137.3 us2.00 us1.67 us121993119405
CompressFastestTestDocument.pdfDeflate947.61 μs17.861 μs18.342 μs121993121404
DecompressFastestTestDocument.pdfBrotli233.14 μs3.625 μs3.391 μs
DecompressFastestTestDocument.pdfZstandard17.22 us0.260 us0.244 us
DecompressFastestTestDocument.pdfDeflate238.81 μs2.153 μs1.908 μs
Supported platforms (verified by CI): Windows, Linux, OSX, Mobile
  • WASM support should be possible, but will need a bit of work to make it opt-in to avoid increasing the runtime size. Will be left for follow-up.
Binary size diff (local debug build, Windows, main vs PR):
NameBeforeAfterDiff
System.IO.Compression.Native.dll4 861 9526 029 8241 167 872
System.IO.Compression.Zstandard.dll054 78454 784
we can probably shave off about 130 kB by removing legacy support (support for formats used by previous zstd versions, see https://deepwiki.com/facebook/zstd/15-legacy-support), but I am not sure if that is worth it.
I wasnt able to check trimmed size of a single-file application, but I expect that roughly +1.1 MB increase due to lack of native pruning capabilities.
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Pull Request Overview
This PR implements ZStandard stream, encoder, and decoder functionality for .NET by integrating the zstd native library. The changes primarily consist of adding the external zstd library source files and build infrastructure to support compression and decompression capabilities.
Key Changes:
  • Integration of zstd native library source code (version metadata suggests 0.9.0)
  • Build system configuration files for Meson and CMake
  • Single-file library generation scripts and examples
  • Test infrastructure for the zstd implementation
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FileDescription
src/native/external/zstd/lib/common/fse_decompress.cFSE (Finite State Entropy) decompression implementation
src/native/external/zstd/lib/common/fse.hFSE codec public API and data structures
src/native/external/zstd/lib/common/error_private.hInternal error handling macros and definitions
src/native/external/zstd/lib/common/error_private.cError code to string mapping implementation
src/native/external/zstd/lib/common/entropy_common.cCommon entropy encoding/decoding functions
src/native/external/zstd/lib/common/debug.hDebug logging and assertion macros
src/native/external/zstd/lib/common/debug.cDebug level global variable definition
src/native/external/zstd/lib/common/cpu.hCPU feature detection (BMI2, AVX, etc.)
src/native/external/zstd/lib/common/compiler.hCompiler-specific macros and attributes
src/native/external/zstd/lib/common/bitstream.hBitstream encoding/decoding utilities
src/native/external/zstd/lib/common/bits.hBit manipulation helper functions
src/native/external/zstd/lib/common/allocations.hCustom memory allocation wrappers
src/native/external/zstd/lib/README.mdDocumentation for library structure and build options
src/native/external/zstd/lib/MakefileBuild configuration for the zstd library
src/native/external/zstd/lib/BUCKBuck build system configuration
src/native/external/zstd/lib/.gitignoreGit ignore rules for build artifacts
src/native/external/zstd/build/single_file_libs/*Scripts and examples for single-file library generation
src/native/external/zstd/build/meson/*Meson build system configuration files
src/native/external/zstd/build/cmake/tests/.gitignoreGit ignore rules for CMake test artifacts
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I think this PR is ready for the first round of reviews
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/ba-g Test failures are unrelated
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Copilot reviewed 46 out of 46 changed files in this pull request and generated no new comments.
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@gewarren Could you please take a look at the documentation comments if it is consistent with what we generally write?
CC also @blowdart@GrabYourPitchforks who also wanted to look at the comments.
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@rzikm I left some suggestions, thanks for tagging me.
Comment threadsrc/libraries/System.IO.Compression.Zstandard/src/Resources/Strings.resx
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Comment thread...ies/System.IO.Compression.Zstandard/src/System/IO/Compression/ZstandardCompressionOptions.cs
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Comment thread...ies/System.IO.Compression.Zstandard/src/System/IO/Compression/ZstandardCompressionOptions.cs
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Comment thread...ies/System.IO.Compression.Zstandard/src/System/IO/Compression/ZstandardCompressionOptions.cs
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Comment thread...ies/System.IO.Compression.Zstandard/src/System/IO/Compression/ZstandardCompressionOptions.cs
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Comment threadsrc/libraries/System.IO.Compression.Zstandard/src/System/IO/Compression/ZstandardEncoder.cs
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Comment threadsrc/libraries/System.IO.Compression.Zstandard/src/System/IO/Compression/ZstandardStream.cs
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Comment threadsrc/libraries/System.IO.Compression.Zstandard/src/System/IO/Compression/ZstandardStream.cs
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Comment threadsrc/libraries/System.IO.Compression.Zstandard/src/System/IO/Compression/ZstandardStream.cs
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Comment threadsrc/libraries/System.IO.Compression.Zstandard/src/System/IO/Compression/ZstandardStream.cs
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Fix some documentation wording
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Revert "fixup! fixup! Enable on WASI/Browser"
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Revert "fixup! Enable on WASI/Browser"
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Implement ZStandard Stream, Encoder, Decoder - #119575
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rzikm:59591-zstd
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Implement ZStandard Stream, Encoder, Decoder#119575
rzikm merged 130 commits into
dotnet:mainfrom 
rzikm:59591-zstd
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Implements #59591
There are some patches applied to vendored zstd sources which are listed in src/native/zstd-version.txt, neither of them should be necessary once we update to next release (maintainers didn't commit to a release date, but hopefully they will release something early next year).
Benchmarks results (taken from dotnet/performance repo) look great so far
 Benchmark results
MethodlevelfileAlgorithmMeanErrorStdDevSizeCompressed
CompressOptimalalice29.txtBrotli2,306.40 μs45.807 μs71.316 μs14848154517
CompressOptimalalice29.txtZstandard842.743 μs8.3719 μs7.8310 μs14848154919
CompressOptimalalice29.txtDeflate2,421.16 μs41.274 μs38.608 μs14848153890
DecompressOptimalalice29.txtBrotli320.82 μs4.802 μs4.257 μs
DecompressOptimalalice29.txtZstandard139.251 μs2.0885 μs1.7440 μs
DecompressOptimalalice29.txtDeflate275.43 μs4.849 μs4.535 μs
CompressOptimalsumBrotli577.62 μs7.647 μs5.971 μs3824012527
CompressOptimalsumZstandard155.050 μs3.0367 μs3.3753 μs3824013389
CompressOptimalsumDeflate404.70 μs7.732 μs9.779 μs3824013388
DecompressOptimalsumBrotli101.26 μs2.781 μs7.566 μs
DecompressOptimalsumZstandard31.333 μs0.6172 μs0.5774 μs
DecompressOptimalsumDeflate54.86 μs0.676 μs0.632 μs
CompressOptimalTestDocument.pdfBrotli763.43 μs13.851 μs23.520 μs121993115863
CompressOptimalTestDocument.pdfZstandard182.115 μs3.3456 μs2.9658 μs121993119285
CompressOptimalTestDocument.pdfDeflate2,133.16 μs42.543 μs104.358 μs121993115369
DecompressOptimalTestDocument.pdfBrotli267.64 μs5.281 μs10.047 μs
DecompressOptimalTestDocument.pdfZstandard17.508 μs0.3336 μs0.3708 μs
DecompressOptimalTestDocument.pdfDeflate224.92 μs2.642 μs2.342 μs
CompressFastestalice29.txtBrotli732.30 μs14.288 μs19.074 μs14848159265
CompressFastestalice29.txtZstandard509.3 us5.10 us4.53 us14848159891
CompressFastestalice29.txtDeflate612.28 μs11.300 μs16.564 μs14848183053
DecompressFastestalice29.txtBrotli380.92 μs7.570 μs9.844 μs
DecompressFastestalice29.txtZstandard111.14 us1.321 us1.103 us
DecompressFastestalice29.txtDeflate361.78 μs6.700 μs14.847 μs
CompressFastestsumBrotli125.26 μs2.489 μs3.801 μs3824014305
CompressFastestsumZstandard108.0 us1.05 us0.88 us3824013848
CompressFastestsumDeflate121.81 μs2.409 μs4.699 μs3824017222
DecompressFastestsumBrotli99.19 μs1.974 μs3.243 μs
DecompressFastestsumZstandard29.01 us0.559 us0.599 us
DecompressFastestsumDeflate58.68 μs0.999 μs0.934 μs
CompressFastestTestDocument.pdfBrotli300.40 μs5.753 μs6.394 μs121993117104
CompressFastestTestDocument.pdfZstandard137.3 us2.00 us1.67 us121993119405
CompressFastestTestDocument.pdfDeflate947.61 μs17.861 μs18.342 μs121993121404
DecompressFastestTestDocument.pdfBrotli233.14 μs3.625 μs3.391 μs
DecompressFastestTestDocument.pdfZstandard17.22 us0.260 us0.244 us
DecompressFastestTestDocument.pdfDeflate238.81 μs2.153 μs1.908 μs
Supported platforms (verified by CI): Windows, Linux, OSX, Mobile
  • WASM support should be possible, but will need a bit of work to make it opt-in to avoid increasing the runtime size. Will be left for follow-up.
Binary size diff (local debug build, Windows, main vs PR):
NameBeforeAfterDiff
System.IO.Compression.Native.dll4 861 9526 029 8241 167 872
System.IO.Compression.Zstandard.dll054 78454 784
we can probably shave off about 130 kB by removing legacy support (support for formats used by previous zstd versions, see https://deepwiki.com/facebook/zstd/15-legacy-support), but I am not sure if that is worth it.
I wasnt able to check trimmed size of a single-file application, but I expect that roughly +1.1 MB increase due to lack of native pruning capabilities.
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Pull Request Overview
This PR implements ZStandard stream, encoder, and decoder functionality for .NET by integrating the zstd native library. The changes primarily consist of adding the external zstd library source files and build infrastructure to support compression and decompression capabilities.
Key Changes:
  • Integration of zstd native library source code (version metadata suggests 0.9.0)
  • Build system configuration files for Meson and CMake
  • Single-file library generation scripts and examples
  • Test infrastructure for the zstd implementation
Reviewed Changes
Copilot reviewed 142 out of 237 changed files in this pull request and generated no comments.
Show a summary per file
FileDescription
src/native/external/zstd/lib/common/fse_decompress.cFSE (Finite State Entropy) decompression implementation
src/native/external/zstd/lib/common/fse.hFSE codec public API and data structures
src/native/external/zstd/lib/common/error_private.hInternal error handling macros and definitions
src/native/external/zstd/lib/common/error_private.cError code to string mapping implementation
src/native/external/zstd/lib/common/entropy_common.cCommon entropy encoding/decoding functions
src/native/external/zstd/lib/common/debug.hDebug logging and assertion macros
src/native/external/zstd/lib/common/debug.cDebug level global variable definition
src/native/external/zstd/lib/common/cpu.hCPU feature detection (BMI2, AVX, etc.)
src/native/external/zstd/lib/common/compiler.hCompiler-specific macros and attributes
src/native/external/zstd/lib/common/bitstream.hBitstream encoding/decoding utilities
src/native/external/zstd/lib/common/bits.hBit manipulation helper functions
src/native/external/zstd/lib/common/allocations.hCustom memory allocation wrappers
src/native/external/zstd/lib/README.mdDocumentation for library structure and build options
src/native/external/zstd/lib/MakefileBuild configuration for the zstd library
src/native/external/zstd/lib/BUCKBuck build system configuration
src/native/external/zstd/lib/.gitignoreGit ignore rules for build artifacts
src/native/external/zstd/build/single_file_libs/*Scripts and examples for single-file library generation
src/native/external/zstd/build/meson/*Meson build system configuration files
src/native/external/zstd/build/cmake/tests/.gitignoreGit ignore rules for CMake test artifacts
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I think this PR is ready for the first round of reviews
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/azp run runtime-extra-platforms
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/ba-g Test failures are unrelated
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Pull request overview
Copilot reviewed 46 out of 46 changed files in this pull request and generated no new comments.
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/azp run runtime-extra-platforms
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@gewarren Could you please take a look at the documentation comments if it is consistent with what we generally write?
CC also @blowdart@GrabYourPitchforks who also wanted to look at the comments.
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@rzikm I left some suggestions, thanks for tagging me.
Comment threadsrc/libraries/System.IO.Compression.Zstandard/src/Resources/Strings.resx
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Comment thread...ies/System.IO.Compression.Zstandard/src/System/IO/Compression/ZstandardCompressionOptions.cs
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Comment thread...ies/System.IO.Compression.Zstandard/src/System/IO/Compression/ZstandardCompressionOptions.cs
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Comment thread...ies/System.IO.Compression.Zstandard/src/System/IO/Compression/ZstandardCompressionOptions.cs
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Comment thread...ies/System.IO.Compression.Zstandard/src/System/IO/Compression/ZstandardCompressionOptions.cs
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Comment threadsrc/libraries/System.IO.Compression.Zstandard/src/System/IO/Compression/ZstandardEncoder.cs
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Comment threadsrc/libraries/System.IO.Compression.Zstandard/src/System/IO/Compression/ZstandardStream.cs
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Comment threadsrc/libraries/System.IO.Compression.Zstandard/src/System/IO/Compression/ZstandardStream.cs
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Comment threadsrc/libraries/System.IO.Compression.Zstandard/src/System/IO/Compression/ZstandardStream.cs
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Comment threadsrc/libraries/System.IO.Compression.Zstandard/src/System/IO/Compression/ZstandardStream.cs
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Fix some documentation wording
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More docs improvements
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Revert "fixup! fixup! Enable on WASI/Browser"
196fbc9
This reverts commit c0917ab.
Revert "fixup! Enable on WASI/Browser"
This reverts commit 2a5e1db.
Revert "Enable on WASI/Browser"
This reverts commit 6013b24.
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filter: invert(1) hue-rotate(180deg) !important;
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filter: invert(1) hue-rotate(180deg) !important;
background: #2d2d44 !important;
border-color: #444 !important;
}
/* Scrollbars */
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::-webkit-scrollbar-thumb { background: #444 !important; }
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/* Selection */
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}
function removeDarkMode() {
var style = document.getElementById('universal-dark-mode-style');
if (style) style.remove();
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if (e.altKey && e.shiftKey && e.key === 'D') {
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enabled = !enabled;
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applyDarkMode();
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observer.observe(document.head, { childList: true });
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})();
}
} catch(__e) { console.warn('[Userscript:Universal Dark Mode]', __e); }
})();
})();

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Implement ZStandard Stream, Encoder, Decoder - #119575
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rzikm merged 130 commits into
dotnet:mainfrom 
rzikm:59591-zstd
Jan 22, 2026
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Implement ZStandard Stream, Encoder, Decoder#119575
rzikm merged 130 commits into
dotnet:mainfrom 
rzikm:59591-zstd
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Implements #59591
There are some patches applied to vendored zstd sources which are listed in src/native/zstd-version.txt, neither of them should be necessary once we update to next release (maintainers didn't commit to a release date, but hopefully they will release something early next year).
Benchmarks results (taken from dotnet/performance repo) look great so far
 Benchmark results
MethodlevelfileAlgorithmMeanErrorStdDevSizeCompressed
CompressOptimalalice29.txtBrotli2,306.40 μs45.807 μs71.316 μs14848154517
CompressOptimalalice29.txtZstandard842.743 μs8.3719 μs7.8310 μs14848154919
CompressOptimalalice29.txtDeflate2,421.16 μs41.274 μs38.608 μs14848153890
DecompressOptimalalice29.txtBrotli320.82 μs4.802 μs4.257 μs
DecompressOptimalalice29.txtZstandard139.251 μs2.0885 μs1.7440 μs
DecompressOptimalalice29.txtDeflate275.43 μs4.849 μs4.535 μs
CompressOptimalsumBrotli577.62 μs7.647 μs5.971 μs3824012527
CompressOptimalsumZstandard155.050 μs3.0367 μs3.3753 μs3824013389
CompressOptimalsumDeflate404.70 μs7.732 μs9.779 μs3824013388
DecompressOptimalsumBrotli101.26 μs2.781 μs7.566 μs
DecompressOptimalsumZstandard31.333 μs0.6172 μs0.5774 μs
DecompressOptimalsumDeflate54.86 μs0.676 μs0.632 μs
CompressOptimalTestDocument.pdfBrotli763.43 μs13.851 μs23.520 μs121993115863
CompressOptimalTestDocument.pdfZstandard182.115 μs3.3456 μs2.9658 μs121993119285
CompressOptimalTestDocument.pdfDeflate2,133.16 μs42.543 μs104.358 μs121993115369
DecompressOptimalTestDocument.pdfBrotli267.64 μs5.281 μs10.047 μs
DecompressOptimalTestDocument.pdfZstandard17.508 μs0.3336 μs0.3708 μs
DecompressOptimalTestDocument.pdfDeflate224.92 μs2.642 μs2.342 μs
CompressFastestalice29.txtBrotli732.30 μs14.288 μs19.074 μs14848159265
CompressFastestalice29.txtZstandard509.3 us5.10 us4.53 us14848159891
CompressFastestalice29.txtDeflate612.28 μs11.300 μs16.564 μs14848183053
DecompressFastestalice29.txtBrotli380.92 μs7.570 μs9.844 μs
DecompressFastestalice29.txtZstandard111.14 us1.321 us1.103 us
DecompressFastestalice29.txtDeflate361.78 μs6.700 μs14.847 μs
CompressFastestsumBrotli125.26 μs2.489 μs3.801 μs3824014305
CompressFastestsumZstandard108.0 us1.05 us0.88 us3824013848
CompressFastestsumDeflate121.81 μs2.409 μs4.699 μs3824017222
DecompressFastestsumBrotli99.19 μs1.974 μs3.243 μs
DecompressFastestsumZstandard29.01 us0.559 us0.599 us
DecompressFastestsumDeflate58.68 μs0.999 μs0.934 μs
CompressFastestTestDocument.pdfBrotli300.40 μs5.753 μs6.394 μs121993117104
CompressFastestTestDocument.pdfZstandard137.3 us2.00 us1.67 us121993119405
CompressFastestTestDocument.pdfDeflate947.61 μs17.861 μs18.342 μs121993121404
DecompressFastestTestDocument.pdfBrotli233.14 μs3.625 μs3.391 μs
DecompressFastestTestDocument.pdfZstandard17.22 us0.260 us0.244 us
DecompressFastestTestDocument.pdfDeflate238.81 μs2.153 μs1.908 μs
Supported platforms (verified by CI): Windows, Linux, OSX, Mobile
  • WASM support should be possible, but will need a bit of work to make it opt-in to avoid increasing the runtime size. Will be left for follow-up.
Binary size diff (local debug build, Windows, main vs PR):
NameBeforeAfterDiff
System.IO.Compression.Native.dll4 861 9526 029 8241 167 872
System.IO.Compression.Zstandard.dll054 78454 784
we can probably shave off about 130 kB by removing legacy support (support for formats used by previous zstd versions, see https://deepwiki.com/facebook/zstd/15-legacy-support), but I am not sure if that is worth it.
I wasnt able to check trimmed size of a single-file application, but I expect that roughly +1.1 MB increase due to lack of native pruning capabilities.
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Pull Request Overview
This PR implements ZStandard stream, encoder, and decoder functionality for .NET by integrating the zstd native library. The changes primarily consist of adding the external zstd library source files and build infrastructure to support compression and decompression capabilities.
Key Changes:
  • Integration of zstd native library source code (version metadata suggests 0.9.0)
  • Build system configuration files for Meson and CMake
  • Single-file library generation scripts and examples
  • Test infrastructure for the zstd implementation
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FileDescription
src/native/external/zstd/lib/common/fse_decompress.cFSE (Finite State Entropy) decompression implementation
src/native/external/zstd/lib/common/fse.hFSE codec public API and data structures
src/native/external/zstd/lib/common/error_private.hInternal error handling macros and definitions
src/native/external/zstd/lib/common/error_private.cError code to string mapping implementation
src/native/external/zstd/lib/common/entropy_common.cCommon entropy encoding/decoding functions
src/native/external/zstd/lib/common/debug.hDebug logging and assertion macros
src/native/external/zstd/lib/common/debug.cDebug level global variable definition
src/native/external/zstd/lib/common/cpu.hCPU feature detection (BMI2, AVX, etc.)
src/native/external/zstd/lib/common/compiler.hCompiler-specific macros and attributes
src/native/external/zstd/lib/common/bitstream.hBitstream encoding/decoding utilities
src/native/external/zstd/lib/common/bits.hBit manipulation helper functions
src/native/external/zstd/lib/common/allocations.hCustom memory allocation wrappers
src/native/external/zstd/lib/README.mdDocumentation for library structure and build options
src/native/external/zstd/lib/MakefileBuild configuration for the zstd library
src/native/external/zstd/lib/BUCKBuck build system configuration
src/native/external/zstd/lib/.gitignoreGit ignore rules for build artifacts
src/native/external/zstd/build/single_file_libs/*Scripts and examples for single-file library generation
src/native/external/zstd/build/meson/*Meson build system configuration files
src/native/external/zstd/build/cmake/tests/.gitignoreGit ignore rules for CMake test artifacts
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I think this PR is ready for the first round of reviews
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/azp run runtime-extra-platforms
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/ba-g Test failures are unrelated
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Pull request overview
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/azp run runtime-extra-platforms
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@gewarren Could you please take a look at the documentation comments if it is consistent with what we generally write?
CC also @blowdart@GrabYourPitchforks who also wanted to look at the comments.
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@rzikm I left some suggestions, thanks for tagging me.
Comment threadsrc/libraries/System.IO.Compression.Zstandard/src/Resources/Strings.resx
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Comment thread...ies/System.IO.Compression.Zstandard/src/System/IO/Compression/ZstandardCompressionOptions.cs
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Comment thread...ies/System.IO.Compression.Zstandard/src/System/IO/Compression/ZstandardCompressionOptions.cs
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Comment thread...ies/System.IO.Compression.Zstandard/src/System/IO/Compression/ZstandardCompressionOptions.cs
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Comment thread...ies/System.IO.Compression.Zstandard/src/System/IO/Compression/ZstandardCompressionOptions.cs
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Comment threadsrc/libraries/System.IO.Compression.Zstandard/src/System/IO/Compression/ZstandardEncoder.cs
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Comment threadsrc/libraries/System.IO.Compression.Zstandard/src/System/IO/Compression/ZstandardStream.cs
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Comment threadsrc/libraries/System.IO.Compression.Zstandard/src/System/IO/Compression/ZstandardStream.cs
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Comment threadsrc/libraries/System.IO.Compression.Zstandard/src/System/IO/Compression/ZstandardStream.cs
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Comment threadsrc/libraries/System.IO.Compression.Zstandard/src/System/IO/Compression/ZstandardStream.cs
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Fix some documentation wording
2be44ca
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More docs improvements
c5f398a
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Revert "fixup! fixup! Enable on WASI/Browser"
196fbc9
This reverts commit c0917ab.
Revert "fixup! Enable on WASI/Browser"
This reverts commit 2a5e1db.
Revert "Enable on WASI/Browser"
This reverts commit 6013b24.
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