sbloghilt.blogg.se - Speed up xz compression

#Speed up xz compression manual#
#Speed up xz compression archive#
#Speed up xz compression full#
#Speed up xz compression software#
#Speed up xz compression code#

^ a b c "Linux Manpages Online - man.cx manual pages".

^ "Gzip vs Bzip2 vs XZ Performance Comparison"."How to squeeze the most out of Linux file compression".

#Speed up xz compression software#

build system and some utilities) are under different free software licenses such as GNU LGPLv2.1, GNU GPLv2, or GNU GPLv3." You can do whatever you want with the public domain parts.

^ a b Licensing on "The most interesting parts of XZ Utils (e.g.

Arch Linux previously used xz to compress packages, but as of December 27, 2019, packages are compressed with Zstandard compression. A number of Linux distributions, including Fedora, Slackware, Ubuntu, and Debian use xz for compressing their software packages. īinaries are available for FreeBSD, NetBSD, Linux systems, Microsoft Windows, and FreeDOS. The resulting software xz and liblzma binaries are public domain, unless the optional LGPL getopt implementation is incorporated.

And the example program scanlzma, which is not integrated with the build system.

Some nonessential wrapper scripts (xzgrep, etc) ( GNU GPL v2).

An m4 script for pthread detection ( GNU GPL v3).

An optional implementation of a common libc function, getopt ( GNU LGPL v2.1).

#Speed up xz compression full#

Specifically, the full list of GPL scripts and sources distributed with the XZ Utils software include: The XZ Utils source distribution additionally includes some optional scripts and an example program that are subject to various versions of the GPL.

#Speed up xz compression code#

The exact filters used are similar to those used in 7z, as 7z's filters are available in the public domain via the LZMA SDK.ĭevelopment of XZ Utils took place within the Tukaani Project, which was led by Mike Kezner, by a small group of developers who once maintained a Linux distribution based on Slackware.Īll of the source code for xz and liblzma has been released into the public domain. The xz format improves on lzma by allowing for preprocessing filters. The number of threads can be less than defined if the file is not big enough for threading with the given settings or if using more threads would exceed the memory usage limit. Threaded decompression requires multiple compressed blocks within a stream which are created by the threaded compression interface. since version 5.4.0 threaded decompression has been implemented. Xz has supported multi-threaded compression (with the -T flag) since 2014, version 5.2.0. Tar xJf keep.txz # decompress then extract the file.

#Speed up xz compression archive#

Tar cJf keep.txz keep # archive then compress the directory. Single-letter tar example for archive with compress and decompress with extract using short suffix: Tar -x -lzma -f my_ # results in /some_directory Tar -x -xz -f my_ # results in /some_directory Tar -c -lzma -f my_ /some_directory # results in my_ĭecompressing the archive and extracting its contents: Tar -c -xz -f my_ /some_directory # results in my_ Version 1.22 or greater of the GNU implementation of tar has transparent support for tarballs compressed with lzma and xz, using the switches -xz or -J for xz compression, and -lzma for LZMA compression. They cannot bundle multiple files into a single archive – to do this an archiving program is used first, such as tar. Just like gzip and bzip, xz and lzma can only compress single files (or data streams) as input. XZ Utils can compress and decompress both the xz and lzma file formats, but since the LZMA format is now legacy, XZ Utils compresses by default to xz.īoth the behavior of the software as well as the properties of the file format have been designed to work similarly to those of the popular Unix compressing tools gzip and bzip2. Various command shortcuts exist, such as lzma (for xz -format=lzma), unxz (for xz -decompress analogous to gunzip) and xzcat (for unxz -stdout analogous to zcat) liblzma, a software library with an API similar to zlib.xz, the command-line compressor and decompressor (analogous to gzip).XZ Utils consists of two major components: Compression can be much slower than gzip, and is slower than bzip2 for high levels of compression, and is most useful when a compressed file will be used many times. Decompression speed is higher than bzip2, but lower than gzip. In most cases, xz achieves higher compression rates than alternatives like gzip and bzip2.

XZ Utils started as a Unix port of Igor Pavlov's LZMA- SDK that has been adapted to fit seamlessly into Unix environments and their usual structure and behavior. For compression/decompression the Lempel–Ziv–Markov chain algorithm (LZMA) is used. XZ Utils (previously LZMA Utils) is a set of free software command-line lossless data compressors, including the programs lzma and xz, for Unix-like operating systems and, from version 5.0 onwards, Microsoft Windows.