4 ms·

Fletcher checksums are very cheap and not a bottleneck. https://github.com/zfsonlinux/zfs/issues/4789#issuecomment-230764245 https://github.com/zfsonlinux/zfs/

• chongli 9y ago
  Maybe I'm reading those benchmarks wrong, but they appear to max out well under 10GB/s. This would mean you'd be CPU bound on your checksums alone with one of those Seagate cards.
  • olavgg 9y ago
    That is a Xeon Phi, a modern Xeon with 10+ cores should do tens of GB/s https://cloud.githubusercontent.com/assets/472018/13333262/fff39076-dbba-11e5-9d24-55d93d018567.png https://cloud.githubusercontent.com/assets/472018/13333262/f... https://github.com/zfsonlinux/zfs/pull/4330 https://github.com/zfsonlinux/zfs/pull/4330
    • dev_tty01 9y ago
      Hmm, I for one don't want to tie up ten cores with IO.
      • ioquatix 9y ago
        If you aren't checksumming your data, is it truely your data?
        • pmarreck 9y ago
          Who checksums the checksummers? ;)
          • ioquatix 9y ago
            Mr Edward Checksum Checker. Update: At least 1 person didn't get this joke :D
          • joshka 9y ago
            You can't handle the checksum
          • deleted 9y ago
            [deleted]
      • blattimwind 9y ago
        > Hmm, I for one don't want to tie up ten cores with IO. What else are you going to use the two CPUs in a filer for?
  • RJIb8RBYxzAMX9u 9y ago
    Although not recommended, you can turn checksum off. The granularity is at the dataset level, too, so you have a lot of flexibility.
  • bobdole1234 9y ago
    On a single thread. ZFS is well pipelined for multicore throughput.