On Fri, Aug 17, 2018 at 09:54:03AM -0700, Andi Kleen wrote: > On Fri, Aug 17, 2018 at 06:15:45PM +0200, René Rebe wrote: > > Hey, > > > > is there any mainline future for this zstd support? > > Currently my most favourite compressor for this, and for what it’s worth > > zstd/initrd now even tested on #t2sde / hp/pa-risc > > Can you remove some other compressor for the kernel image if you merge this?
Funny you say this. I want to post this after the merge window is over: https://github.com/kilobyte/linux/commits/nobz2-next-20180731 Sorry for a tree atop next, but there are conflicts that needed to be adressed. The patchset is also undertested (works for me, but not even compile-tested on archs I don't have a toolchain for at hand). > The "favourite compressor" seems to roughly change every year, so if > we keep adding new ones things will get more and more convoluted. The above patchset drops just bzip2. It is the only one that's strictly beaten in every way (ratio, time, memory usage), there are also no other uses of bzip2 anywhere in the kernel so we'd get to drop its code completely: 900 lines of Linus' happiness. Other candidates are lzo and bare lzma (you want lz4, zstd or xz instead), but those are used elsewhere thus there's hardly any gain. If you want them gone, please say so -- I'll include their droppage. > Surely zstd is universally better than some existing compressor > the kernel already uses for itself for a particular sweet spot? > If it isn't it's likely not needed. zstd is better in the balanced niche: unless you want extreme speed (lz4) or best compression (xz), zstd handily beats algorithms in the middle. Meow! -- ⢀⣴⠾⠻⢶⣦⠀ What Would Jesus Do, MUD/MMORPG edition: ⣾⠁⢰⠒⠀⣿⡁ • multiplay with an admin char to benefit your mortal [Mt3:16-17] ⢿⡄⠘⠷⠚⠋⠀ • abuse item cloning bugs [Mt14:17-20, Mt15:34-37] ⠈⠳⣄⠀⠀⠀⠀ • use glitches to walk on water [Mt14:25-26]
