4bd7990488
zstd with its default settings (compression level -3) compresses better than bzip2 -9 (which is the default setting), and is an order of magnitude faster. I made the following measurements for the most common compression tools (all standard Debian Buster versions, default flags unless noted otherwise), using the debug information of a large x86-64 kernel with ALL_KMODS: * kernel-debug.tar: 376M * kernel-debug.tar.gz: 101M, compressed in ~12s * kernel-debug.tar.bz2: 91M, compressed in ~15s * kernel-debug.tar.xz: 57M, compressed in ~101s * kernel-debug.tar.zst: 86M, compressed in ~1s With zstd, there is still some room for improvement by increasing the compression, but the slight increase in compression ratio (22.83% -> 19.46%) does not justify the significant increase in compression time (about 5 times on my machine) in my opinion. Note that multithreaded compression (-T argument) does not affect reproducibility with zstd. Signed-off-by: Matthias Schiffer <mschiffer@universe-factory.net>
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|__| W I R E L E S S F R E E D O M
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This is the buildsystem for the OpenWrt Linux distribution.
To build your own firmware you need a Linux, BSD or MacOSX system (case
sensitive filesystem required). Cygwin is unsupported because of the lack
of a case sensitive file system.
You need gcc, binutils, bzip2, flex, python3.5+, perl, make, find, grep, diff,
unzip, gawk, getopt, subversion, libz-dev and libc headers installed.
1. Run "./scripts/feeds update -a" to obtain all the latest package definitions
defined in feeds.conf / feeds.conf.default
2. Run "./scripts/feeds install -a" to install symlinks for all obtained
packages into package/feeds/
3. Run "make menuconfig" to select your preferred configuration for the
toolchain, target system & firmware packages.
4. Run "make" to build your firmware. This will download all sources, build
the cross-compile toolchain and then cross-compile the Linux kernel & all
chosen applications for your target system.
Sunshine!
Your OpenWrt Community
http://www.openwrt.org