I was considering looking into installing Void with ZFS on root if I ever need to reinstall the OS on my computer. So far the advantages I have read about have been mostly about snapshotting and restoration but I am admittedly more interested because it’s a shiny new file system.

I am using a laptop with 250GB SSD. Would I benefit from using ZFS? Or is it overhyped? Any input is appreciated.

  • @ksynwaOP
    2•4 years ago

    That is actually super good. I will have to look into the CPU overhead for compression/decompression.

    Thanks for the detailed answer.

    • @jetlego
      2•4 years ago

      Here’s some extremely unscientific data I collected:

      CPU: Ryzen 2600x with PBO limits maxed
zstd:1 - 38% compression ratio, ~1000MB/s write speed, all cores maxed out
zstd:3 - 35% compression ratio, ~800MB/s write speed, all cores maxed out
zstd:9 - 33% compression ratio, ~217MB/s write speed, all cores between 50% - 100% while running

CPU: Ryzen 2600x cTDP set to 35 watts and only 2 cores & 4 threads enabled to simulate a weak processor
zstd:1 - 400MB/s
zstd:3 - 300MB/s
zstd:9 - 82MB/s

Same compression ratios and CPU usage

      Notes:

      • A NVME SSD with a sequential write speed of >1000MB/s was used.
      • The command used for testing was “pv enwik9 enwik9 enwik9 enwik9 enwik9 enwik9> enwik9.6” where enwik9 is the file from http://prize.hutter1.net/
      • The BTRFS filesystem was on a LUKS encrypted device so there was some AES overhead, but the 2600x supports hardware accelerated AES instructions so it shouldn’t play that large of a role
      • vm.dirty.ratio set to 1
      • Cores enabled were 1 on each CCX
      • Decompression was too fast and was bottlenecked by the SSD
      • @ksynwaOP
        2•4 years ago

        This is some great work. Thank you very much.