Re: [OE-core] [PATCH V2] archiver: Configurable tarball compression
From: Michael Opdenacker <hidden>
Date: 2021-09-21 13:48:33
On 9/21/21 3:20 PM, Michael Opdenacker wrote:
By the way, zstd seems to be marginally worse (+1%) than xz in terms of compressed size, but is orders of magnitude faster (see https://archlinux.org/news/now-using-zstandard-instead-of-xz-for-package-compression/).
Actually, this article only mentions decompression speed, but that's also true for compression speed. Here are my own tests: mike@mike-laptop:~/tmp$ time gzip linux-5.15-rc2.tar real 0m29.293s user 0m28.712s sys 0m0.553s mike@mike-laptop:~/tmp$ time xz linux-5.15-rc2.tar real 7m2.658s user 7m1.096s sys 0m1.280s mike@mike-laptop:~/tmp$ time zstd linux-5.15-rc2.tar linux-5.15-rc2.tar : 16.29% (1136803840 => 185233271 bytes, linux-5.15-rc2.tar.zst) real 0m5.476s user 0m5.530s sys 0m0.864s mike@mike-laptop:~/tmp$ ls -la linux-5.15* -rw-rw-r-- 1 mike mike 1136803840 Sep 21 15:31 linux-5.15-rc2.tar -rw-rw-r-- 1 mike mike 198135832 Sep 21 15:24 linux-5.15-rc2.tar.gz -rw-rw-r-- 1 mike mike 125980548 Sep 21 15:26 linux-5.15-rc2.tar.xz -rw-rw-r-- 1 mike mike 185233271 Sep 21 15:31 linux-5.15-rc2.tar.zst So, here the claim that zstd (with default options) is almost as good as xz in compressed size is not confirmed. However, zstd is a clear winner in terms of compression speed, and anyway better than gzip. This is worth switching. Cheers Michael -- Michael Opdenacker, Bootlin Embedded Linux and Kernel engineering https://bootlin.com