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Move the implementation of programs/benchfn.c into rust/src/benchfn.rs and wire benchmark mode (-b/-e/-i) into the Rust CLI frontend, which previously rejected those options as not yet implemented. `zstd -b1 -i0 FILE` and range runs like `zstd -b5e6 -i0 FILE` work again, including the synthetic-sample benchmark when no file is given. benchfn.rs is a faithful port of the run/timing state machine: BMK_benchFunction keeps the exact loop accounting (first-loop blockResults and errorFn checks, dstSize summed on the first loop only, 0xE5 warm-up of result buffers, nbLoops minimum of 1) and BMK_benchTimedFn keeps the same convergence behavior (x10 workload growth for short runs, budget-based nbLoops estimation, runs below half the run budget re-tried rather than reported, best qualifying run returned). Arithmetic that C leaves to unsigned wrap-around uses wrapping operations so debug builds cannot panic where release C would wrap. ABI notes: BMK_runTime_t and BMK_runOutcome_t are returned by value across the C boundary and BMK_benchParams_t is passed by value, so all three are repr(C) mirrors of benchfn.h; their field offsets are pinned by const asserts in Rust and matching C static asserts in the benchfn.c shim, which is now declaration-only. BMK_timedFnState_t stays opaque, fits the 64-byte BMK_timedFnState_shell (compile-time checked), and is malloc/free-managed so creation and destruction remain interchangeable with C callers. The CLI parses -b (bench mode), -e (range end, digits attach directly, defaulting to 0 like readU32FromChar) and -i (duration in seconds), then dispatches through a new ZSTD_rust_cli_bench bridge in the zstdcli.c shim. The bridge exists because benchmark availability is a C preprocessor property (ZSTD_NOBENCH): orchestration and reporting stay in C benchzstd.c, stripped variants (zstd-small, zstd-compress, zstd-decompress) compile the stub branch and report "benchmark mode is not available in this build", and the Rust side never references benchmark symbols directly. Level clamping against ZSTD_maxCLevel() happens in the bridge, where the symbol is guaranteed to exist whenever benchmarking is compiled in. -T selects the worker count, defaulting to single-threaded like the C bench path; -S (separate files) and --priority=rt remain unimplemented. Makefile updates only extend the Rust source prerequisite lists with benchfn.rs; the helpers-archive plumbing from the timefn commit already links fullbench(-lib/-dll/32) and paramgrill, the benchfn consumers among the C tests. Original C test sources are untouched. Known pre-existing issues, unchanged by this commit: tests/fullbench-lib fails to link at the base commit too (libzstd.a precedes fullbench.c in its link line), and the cli-tests basic/help.sh, compression/levels.sh, compression/golden.sh, and decompression/pass-through.sh scripts fail identically with a base-commit binary because the Rust CLI frontend is still a partial reimplementation. Test Plan: - cd rust && cargo fmt --check && cargo clippy --all-targets -- -D warnings && cargo test --all-targets && cargo build --release - cd rust/cli && cargo fmt --check && cargo clippy --all-targets -- -D warnings && cargo test --all-targets; repeat tests with --no-default-features plus features compression / decompression / (none) - make -C programs zstd; ./programs/zstd -b1 -i0 lib/common/xxhash.c; ./programs/zstd -b5e6 -i0 programs/fileio.c; ./programs/zstd -b1 -i0 (synthetic); echo roundtrip via zstd | zstd -d - make -C programs zstd-small zstd-compress zstd-decompress zstd-nolegacy zstd-dictBuilder; zstd-small -b reports benchmark unavailable; compress/ decompress roundtrip across the split binaries - make -C tests fullbench fuzzer zstreamtest paramgrill decodecorpus poolTests fullbench32 fuzzer32; ./tests/fullbench -i0 (exercises Rust BMK_benchTimedFn from C); ./tests/fullbench32 -i0; ./tests/fuzzer -i1 --no-big-tests; ./tests/poolTests; make -C tests test-rust-lib-smoke - cli-tests subset: basic/version.sh, compression/basic.sh, compression/multiple-files.sh pass; failing scripts match the base commit Refs: rust/README.md
Zstandard, or zstd as short version, is a fast lossless compression algorithm,
targeting real-time compression scenarios at zlib-level and better compression ratios.
It's backed by a very fast entropy stage, provided by Huff0 and FSE library.
Zstandard's format is stable and documented in RFC8878. Multiple independent implementations are already available.
This repository represents the reference implementation, provided as an open-source dual BSD OR GPLv2 licensed C library,
and a command line utility producing and decoding .zst, .gz, .xz and .lz4 files.
Should your project require another programming language,
a list of known ports and bindings is provided on Zstandard homepage.
Development branch status:
Benchmarks
For reference, several fast compression algorithms were tested and compared
on a desktop featuring a Core i7-9700K CPU @ 4.9GHz
and running Ubuntu 20.04 (Linux ubu20 5.15.0-101-generic),
using lzbench, an open-source in-memory benchmark by @inikep
compiled with gcc 9.4.0,
on the Silesia compression corpus.
| Compressor name | Ratio | Compression | Decompress. |
|---|---|---|---|
| zstd 1.5.6 -1 | 2.887 | 510 MB/s | 1580 MB/s |
| zlib 1.2.11 -1 | 2.743 | 95 MB/s | 400 MB/s |
| brotli 1.0.9 -0 | 2.702 | 395 MB/s | 430 MB/s |
| zstd 1.5.6 --fast=1 | 2.437 | 545 MB/s | 1890 MB/s |
| zstd 1.5.6 --fast=3 | 2.239 | 650 MB/s | 2000 MB/s |
| quicklz 1.5.0 -1 | 2.238 | 525 MB/s | 750 MB/s |
| lzo1x 2.10 -1 | 2.106 | 650 MB/s | 825 MB/s |
| lz4 1.9.4 | 2.101 | 700 MB/s | 4000 MB/s |
| lzf 3.6 -1 | 2.077 | 420 MB/s | 830 MB/s |
| snappy 1.1.9 | 2.073 | 530 MB/s | 1660 MB/s |
The negative compression levels, specified with --fast=#,
offer faster compression and decompression speed
at the cost of compression ratio.
Zstd can also offer stronger compression ratios at the cost of compression speed. Speed vs Compression trade-off is configurable by small increments. Decompression speed is preserved and remains roughly the same at all settings, a property shared by most LZ compression algorithms, such as zlib or lzma.
The following tests were run
on a server running Linux Debian (Linux version 4.14.0-3-amd64)
with a Core i7-6700K CPU @ 4.0GHz,
using lzbench, an open-source in-memory benchmark by @inikep
compiled with gcc 7.3.0,
on the Silesia compression corpus.
| Compression Speed vs Ratio | Decompression Speed |
|---|---|
 |
 |
A few other algorithms can produce higher compression ratios at slower speeds, falling outside of the graph. For a larger picture including slow modes, click on this link.
The case for Small Data compression
Previous charts provide results applicable to typical file and stream scenarios (several MB). Small data comes with different perspectives.
The smaller the amount of data to compress, the more difficult it is to compress. This problem is common to all compression algorithms, and reason is, compression algorithms learn from past data how to compress future data. But at the beginning of a new data set, there is no "past" to build upon.
To solve this situation, Zstd offers a training mode, which can be used to tune the algorithm for a selected type of data. Training Zstandard is achieved by providing it with a few samples (one file per sample). The result of this training is stored in a file called "dictionary", which must be loaded before compression and decompression. Using this dictionary, the compression ratio achievable on small data improves dramatically.
The following example uses the github-users sample set, created from github public API.
It consists of roughly 10K records weighing about 1KB each.
| Compression Ratio | Compression Speed | Decompression Speed |
|---|---|---|
 |
 |
 |
These compression gains are achieved while simultaneously providing faster compression and decompression speeds.
Training works if there is some correlation in a family of small data samples. The more data-specific a dictionary is, the more efficient it is (there is no universal dictionary). Hence, deploying one dictionary per type of data will provide the greatest benefits. Dictionary gains are mostly effective in the first few KB. Then, the compression algorithm will gradually use previously decoded content to better compress the rest of the file.
Dictionary compression How To:
-
Create the dictionary
zstd --train FullPathToTrainingSet/* -o dictionaryName -
Compress with dictionary
zstd -D dictionaryName FILE -
Decompress with dictionary
zstd -D dictionaryName --decompress FILE.zst
Build instructions
make is the officially maintained build system of this project.
All other build systems are "compatible" and 3rd-party maintained,
they may feature small differences in advanced options.
When your system allows it, prefer using make to build zstd and libzstd.
Makefile
If your system is compatible with standard make (or gmake),
invoking make in root directory will generate zstd cli in root directory.
It will also create libzstd into lib/.
Other available options include:
make install: create and install zstd cli, library and man pagesmake check: create and runzstd, test its behavior on local platform
The Makefile follows the GNU Standard Makefile conventions,
allowing staged install, standard flags, directory variables and command variables.
For advanced use cases, specialized compilation flags which control binary generation
are documented in lib/README.md for the libzstd library
and in programs/README.md for the zstd CLI.
cmake
A cmake project generator is provided within build/cmake.
It can generate Makefiles or other build scripts
to create zstd binary, and libzstd dynamic and static libraries.
By default, CMAKE_BUILD_TYPE is set to Release.
Support for Fat (Universal2) Output
zstd can be built and installed with support for both Apple Silicon (M1/M2) as well as Intel by using CMake's Universal2 support.
To perform a Fat/Universal2 build and install use the following commands:
cmake -B build-cmake-debug -S build/cmake -G Ninja -DCMAKE_OSX_ARCHITECTURES="x86_64;x86_64h;arm64"
cd build-cmake-debug
ninja
sudo ninja install
Meson
A Meson project is provided within build/meson. Follow
build instructions in that directory.
You can also take a look at .travis.yml file for an
example about how Meson is used to build this project.
Note that default build type is release.
VCPKG
You can build and install zstd vcpkg dependency manager:
git clone https://github.com/Microsoft/vcpkg.git
cd vcpkg
./bootstrap-vcpkg.sh
./vcpkg integrate install
./vcpkg install zstd
The zstd port in vcpkg is kept up to date by Microsoft team members and community contributors. If the version is out of date, please create an issue or pull request on the vcpkg repository.
Conan
You can install pre-built binaries for zstd or build it from source using Conan. Use the following command:
conan install --requires="zstd/[*]" --build=missing
The zstd Conan recipe is kept up to date by Conan maintainers and community contributors. If the version is out of date, please create an issue or pull request on the ConanCenterIndex repository.
Visual Studio (Windows)
Going into build directory, you will find additional possibilities:
- Projects for Visual Studio 2005, 2008 and 2010.
- VS2010 project is compatible with VS2012, VS2013, VS2015 and VS2017.
- Automated build scripts for Visual compiler by @KrzysFR, in
build/VS_scripts, which will buildzstdcli andlibzstdlibrary without any need to open Visual Studio solution.
Buck
You can build the zstd binary via buck by executing: buck build programs:zstd from the root of the repo.
The output binary will be in buck-out/gen/programs/.
Bazel
You easily can integrate zstd into your Bazel project by using the module hosted on the Bazel Central Repository.
Testing
You can run quick local smoke tests by running make check.
If you can't use make, execute the playTest.sh script from the src/tests directory.
Two env variables $ZSTD_BIN and $DATAGEN_BIN are needed for the test script to locate the zstd and datagen binary.
For information on CI testing, please refer to TESTING.md.
Status
Zstandard is currently deployed within Facebook and many other large cloud infrastructures. It is run continuously to compress large amounts of data in multiple formats and use cases. Zstandard is considered safe for production environments.
License
Zstandard is dual-licensed under BSD OR GPLv2.
Contributing
The dev branch is the one where all contributions are merged before reaching release.
If you plan to propose a patch, please commit into the dev branch, or its own feature branch.
Direct commit to release are not permitted.
For more information, please read CONTRIBUTING.