isal-rs

Rust bindings for isa-l

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Supports the following codecs using the ISA-L library under the hood:

• GZIP
  • isal::read::GzipEncoder/GzipDecoder
  • isal::write::GzipEncoder/GzipDecoder
• DEFLATE
  • isal::read::DeflateEncoder/DeflateDecoder
  • isal::write::DeflateEncoder/DeflateDecoder
• ZLIB
  • isal::read::ZlibEncoder/ZlibDecoder
  • isal::write::ZlibEncoder/ZlibDecoder

Or can use functions of de/compress and de/compress_into

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Building requires some system tools like autotools, nasm, make, and anything the official ISA-L repo suggests. On Windows the build is invoked with nmake, other systems use the ./autogen.sh and ./configure setups.

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Examples:

Functions like compress_into and decompress

(Similar functionality with compress and decompress_into)

use isal::{CompressionLevel, Codec, compress_into, decompress};

let mut compressed = vec![0u8; 100];
let nbytes = compress_into(b"foobar", &mut compressed, CompressionLevel::Three, Codec::Gzip).unwrap();

let decompressed = decompress(&compressed[..nbytes], Codec::Gzip).unwrap();
assert_eq!(decompressed.as_slice(), b"foobar");

Compress using the Encoder/Decoder structs implementing io::Read

use std::{io, io::Read};
use isal::{read::{Encoder, GzipEncoder}, CompressionLevel, decompress, Codec};

let data = b"Hello, World!".to_vec();

// Note these two encoders are equivelent...
let mut encoder = GzipEncoder::new(data.as_slice(), CompressionLevel::Three);
let mut encoder = Encoder::new(data.as_slice(), CompressionLevel::Three, Codec::Gzip);

// Number of compressed bytes written to `output`
let mut compressed = vec![];
let n = io::copy(&mut encoder, &mut compressed).unwrap();
assert_eq!(n as usize, compressed.len());

let decompressed = decompress(compressed.as_slice(), Codec::Gzip).unwrap();
assert_eq!(decompressed.as_slice(), data);

Decompress using the Encoder/Decoder structs implementing io::Write

use std::{io, io::Write};
use isal::{write::Decoder, CompressionLevel, compress, Codec};

let data = b"Hello, World!".to_vec();
let compressed = compress(data.as_slice(), CompressionLevel::Three, Codec::Gzip).unwrap();

let mut decompressed = vec![];
let mut decoder = Decoder::new(&mut decompressed, Codec::Gzip);

// Number of compressed bytes written to `output`
let n = io::copy(&mut io::Cursor::new(&compressed), &mut decoder).unwrap();
assert_eq!(n as usize, compressed.len());

assert_eq!(decompressed.as_slice(), data);

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Benchmarks

TL/DR: It's roughly 5-10x faster than flate2 with the default features, and ~2-3x faster using flate2 with zlib-ng backend.

Checkout the README in the benches directory. Criterion benchmark report available here: https://milesgranger.github.io/isal-rs/benches/criterion/report/

NOTE: ISA-L supports compression levels 0, 1, 3. These benchmarks compare gzip using compression level 3 for both flate2 and isal-rs.

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Versioning:

Versions are specified in normal SemVer format, and a trailing "+<< commit hash >>" to indicate which commit in isa-l the crate is built against. ie: 0.1.0+62519d9