> On Mar 31, 2020, at 8:11 AM, Sedat Dilek <sedat.dilek@xxxxxxxxx> wrote: > > On Tue, Mar 31, 2020 at 6:15 AM Nick Terrell <terrelln@xxxxxx> wrote: > > [...] > >>> Do you plan to push this for Linux v5.7? >> >> I hope that it will be accepted. From my point of view this patch set is >> ready for merge, except for the maximum window size increase >> requested by Petr. >> > > Hi Nick, > > thanks for your answer. > > Did you send out a pull-request already? I haven’t sent out a pull request. If that is something that I need to do, or if it makes the process easier for a maintainer to merge then I can do that. > Can you point me to that request or patch of Petr? > Is it relevant or optional for the pull-request? The patches from Petr are a parallel implementation of initramfs decompression and are available here [0]. They support initramfs compression well, but are missing some pieces for correct and performant zstd kernel decompression. Namely the equivalent of patch 6 in this series to increase ZO_z_extra_bytes, the performance fix in patch 1 that switches memcpy() to __builtin_memcpy(), and the decompress_single() function in patch 3. Without those changes a very compressible kernel may fail to decompress successfully, and will be corrupted. And the performance is about 4x worse on x86_64. My patches took 70 ms to decompress vs 318 ms with Petr’s. See the detailed comparison here [1]. >>> Feel free to add credits for the whole series: >>> >>> Tested-by: Sedat Dilek <sedat.dilek@xxxxxxxxx> >> >> Thanks for testing the patch set Sedat! >> > > I have re-tested zstd-v3 patchset with Linux version 5.6 final and > Clang/LLD version 10.0.0 final (from Debian/unstable repository). > > Is it possible to mention that there might distro-specific changes > needed to initramfs-handling? > For Debian you are welcome to include below Link [1]. > Not sure I will send/ask to/on the debian-kernel mailing list in this topic. I don’t expect any distro specific changes are required to continue operating as-is. However, if a distro wanted to switch to a zstd compressed initramfs they would need to update their toolchain to compress with zstd. > Thanks and bonne chance. > > Regards, > - Sedat - > > [1] LINK: https://lore.kernel.org/lkml/CA+icZUXCn2an9aNDrm+-eneSAOyGibz0W1xYhwkA5k3B3U-5vQ@xxxxxxxxxxxxxx/ [0] https://lkml.org/lkml/2020/3/16/461 [1] https://lkml.org/lkml/2020/3/31/1573
