@cborntra v5.13 ubuntu kernel's s390 configuration with zstd -22 --ultra compression is 8.5 MB, whereas gzip -9 is 11M.
Thus for gzip to win at bootspeed the decompression speed has to compensate for 2.5M of i/o and be faster than zstd. Unaccelerated decompression comparison still gives me faster decompression with less i/o with zstd compressed kernel image. At Canonical we still do not have z15 mainframe available for us to benchmark this. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1931725 Title: initramfs-tools & kernel: use zstd as the default compression method To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu-z-systems/+bug/1931725/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs