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Google snappy in C for Linux Kernel
C Python Makefile Shell Other
Latest commit c5bedba @zeevt Merge pull request #28 from ikruglov/master
endian.h and mingw (same as PR #27)
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python move python toys
testdata check for memeory leaks
.gitignore add `make` byproduct to .gitignore
Makefile This patch adds two new "make install" arguments:
README updated readme
block_compressor.c use 8kb work memory to compress 4kb pages, like google's code.
block_compressor_benchmark.txt update userspace benchmarks
cl_tester.c cl_tester -S d test failed on AArch64 when decompressing data without
csnappy.h Fix issue #20 from zeevt/csnappy: include stdint.h
csnappy_compat.h Sereal's csnappy Win32 fixes
csnappy_compress.c Fix 64 bit big endian code path in decoder.
csnappy_decompress.c Fix integer truncation error during decompression
csnappy_internal.h Sereal's csnappy Win32 fixes
csnappy_internal_userspace.h endian.h and mingw (same as PR #27)
debugfs_input.txt zram now uses headerless snappy streams to save 2 bytes and a few cpu…
kernel_3_2_10.patch a current linux kernel patch
snappy_tester.patch update snappy tester patch
unaligned_arm.s ARM optimizations. There will be more. In particular ARMv6 has unalig…
unaligned_test.c tester for ARM on android
userspace_benchmark.txt update userspace benchmarks
zram_benchmark.txt split zram benchmark from readme big endian fixes, courtesy of debian ppc qemu image


Google Snappy, available at
is a compression library designed for speed rather than compression ratios.

It is not a new concept by far. The Linux kernel currently uses LZO as the
 default fast compressor. Snappy works faster, though achieves less compression.

Google's code is written in C with a lot of C++. Some of the more interesting
 features that rely on C++ appear to have been elided from the open source
 version of Snappy.

To get the codebase into a shape that can be accepted into the mainline
 Linux kernel and used with zram (
Being able to compress vmlinux and initrd with Snappy is a secondary goal.
Same for support in Squashfs and other parts of the kernel that currently
 support LZO.

I cut out or ported to plain ANSI C the necessary code and headers.
To cause less confusion, I call this project (and files) csnappy.
The API looks right, but I welcome comments.
The code *has* been tested in kernel-space using a patched zram and it works.

The code has been tested in a qemu emulating a PowerPC Mac and ARMv5TE running
 Debian Wheezy.

I also use an ARMv6 Android phone for testing.

Testing on other hardware or platforms is welcome.

Note: The userspace tester is a hack, as is the shared library.

Someone wrote a perl wrapper for csnappy:

Patch for upstream snappy tester is available: snappy_tester.patch
Patch for linux kernel is available: kernel_3_2_10.patch

Benchmark in userspace: userspace_benchmark.txt
Benchmark in kernel space with zram: zram_benchmark.txt
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