Announcement

Collapse
No announcement yet.

Ubuntu 18.10 Looking At LZ4-Compressed Initramfs Image By Default

Collapse
X
  • Filter
  • Time
  • Show
Clear All
new posts

  • Ubuntu 18.10 Looking At LZ4-Compressed Initramfs Image By Default

    Phoronix: Ubuntu 18.10 Looking At LZ4-Compressed Initramfs Image By Default

    With Ubuntu 18.10 being the release after an LTS cycle, it's shaping up to be another big feature period. They have already been discussing Zstd-compressed Debian packages for Ubuntu 18.10 while the latest proposal for this next cycle is on switching from Gzip to LZ4 for the default kernel initramfs image...

    http://www.phoronix.com/scan.php?pag...amfs-LZ4-Plans

  • #2
    90 seconds - 1 = 89 for me. If this feature doesn't herald the year of the Linux desktop then I don't know what does.

    Comment


    • #3
      1 second off of what? Their PC with 8 cores and SSD or 1 second off a PC with a HDD and 2 cores?

      On my old laptop the initramfs extraction time decreased from ~1.2s to ~0.24s: (with lz4)
      Last edited by profoundWHALE; 03-19-2018, 02:01 PM.

      Comment


      • #4
        No reason to do LZ4 for initrd, unless you have really weak CPUs. LZ4 compression ratio is poor. LZ4 is really only useful if your compression/decompression performance matters A LOT. For example, for transparently compressing network traffic at >200 MB/s on the fly.

        ZSTD is much better for initrd IMO. It has both faster performance, and compression ratios that are similar or better compared to gzip.

        Comment


        • #5
          Originally posted by coder111 View Post
          No reason to do LZ4 for initrd, unless you have really weak CPUs. LZ4 compression ratio is poor. LZ4 is really only useful if your compression/decompression performance matters A LOT. For example, for transparently compressing network traffic at >200 MB/s on the fly.

          ZSTD is much better for initrd IMO. It has both faster performance, and compression ratios that are similar or better compared to gzip.
          ACK +1 from me, testing zstd initramfs since a month or two, https://t2sde.org ,-)

          Comment


          • #6
            I'm using an uncompressed initramfs on Arch: decompression time = 0s.
            But yeah, only useful on a SSD.

            Comment


            • #7
              Let's change stuff for the sake of changing stuff. Backwards compatibility is a Microsoft thing, it has to be avoided at all costs.

              Comment


              • #8
                Originally posted by eydee View Post
                Let's change stuff for the sake of changing stuff. Backwards compatibility is a Microsoft thing, it has to be avoided at all costs.
                When would you need to be able to decompress an initramfs that wasn't paired and thus generated with the kernel you're trying to boot? Also, the Ubuntu Kernel by default enables all decompression algorithms for initramfs.

                Comment


                • #9
                  Originally posted by nils_ View Post

                  When would you need to be able to decompress an initramfs that wasn't paired and thus generated with the kernel you're trying to boot? Also, the Ubuntu Kernel by default enables all decompression algorithms for initramfs.
                  I'm not really familiar with the inner workings of initramfs and the early boot process, but maybe it also affects the boot loader (GRUB etc.), not just the kernel?

                  Comment


                  • #10
                    Originally posted by coder111 View Post
                    No reason to do LZ4 for initrd, unless you have really weak CPUs. LZ4 compression ratio is poor.
                    Why even use compression if you have SSD at least? My initrd is about 2.8MB with gzip, 4.1MB with LZ4 or 9MB uncompressed. I doubt that makes a difference for a drive that reads at up to 530MB/s. I don't think the time saved reading 1.3MB gzip vs time to decompress(I haven't measured but there is a quote earlier in the comments about 1.2 secs to 0.24 secs by switching gzip to lz4. Chances are that's a better gain :P LZ4 has a strong decompression ratio, stronger than ZSTD afaik? I'm a fan of zstd and look forward to being able to give it a go anyway.

                    Comment

                    Working...
                    X