Updated XZ Code For The Kernel Looks Like It's Ready For Linux 6.12

[phoronix]

Phoronix: Updated XZ Code For The Kernel Looks Like It's Ready For Linux 6.12

The past few months have seen patches for updating the XZ (de)compression code within the Linux kernel that's been a lengthy process in part due to the XZ backdoor situation earlier this year and the reputable XZ developers in turn being busy cleaning up that mess. In any event it appears that the updated XZ code for the Linux kernel is now on track for mainlining come Linux 6.12...

https://www.phoronix.com/news/XZ-Update-Linux-6.12-Queue

[caligula]

Does it make sense to use this? zstd has been a lot faster recently.

[grigi]

LZMA decompresses very fast, about the speed of regular GZip. Compression times are pretty bad though.
I think it's a case of XZ being fast enough ito decompression, and uses less RAM than ZSTD to decompress, and results in a slightly smaller image.

So likely a worthwhile tradeoff for smaller systems with less storage or RAM available.

[skeevy420]

I can't be the only one who thought something like this:

[milkylainen]

Does it make sense to use this? zstd has been a lot faster recently.

Faster, smaller, better, etc. They all have different attributes.
And I'm happy I have access to them all.
I use most of them for various purposes.

[Weasel]

Does it make sense to use this? zstd has been a lot faster recently.

And bigger.

[fulalas]

And bigger.

I performed some tests using kernel 6.10.2 compiled for PorteuX 1.5. Here are the results:

vmlinuz XZ -> size 8.5 MB / decompress time 0m0.255s
vmlinuz ZSTD -> size 10.0 MB / decompress time 0m0.051s

To decompress I used this script: https://github.com/torvalds/linux/bl...xtract-vmlinux

The commands used were:

time sh extract-vmlinux.sh vmlinuz-xz > decompressed-xz.txt
time sh extract-vmlinux.sh vmlinuz-zstd > decompressed-zstd.txt

[caligula]

I performed some tests using kernel 6.10.2 compiled for PorteuX 1.5. Here are the results:

vmlinuz XZ -> size 8.5 MB / decompress time 0m0.255s
vmlinuz ZSTD -> size 10.0 MB / decompress time 0m0.051s

Great work. BTW the size difference is much larger on rpi size hardware, but even that 0,2 seconds seems like a waste if it only saves around 1,5 MB. Typical hard drive these days is 1 to 2 TB NVMe SSD.

[Weasel]

I performed some tests using kernel 6.10.2 compiled for PorteuX 1.5. Here are the results:

vmlinuz XZ -> size 8.5 MB / decompress time 0m0.255s
vmlinuz ZSTD -> size 10.0 MB / decompress time 0m0.051s

To decompress I used this script: https://github.com/torvalds/linux/bl...xtract-vmlinux

The commands used were:

time sh extract-vmlinux.sh vmlinuz-xz > decompressed-xz.txt
time sh extract-vmlinux.sh vmlinuz-zstd > decompressed-zstd.txt

The defaults (for compression) sometimes suck. Try with: export XZ_OPT="-9e --x86 --lzma2=dict=128M,nice=273,depth=4096,pb=0,lc=4"

before building.