[lkml]   [2003]   [Dec]   [17]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
    SubjectRe: raid0 slower than devices it is assembled of?
    In article <>,
    Linus Torvalds <> wrote:
    | On Wed, 17 Dec 2003, Peter Zaitsev wrote:
    | >
    | > I'm pretty curious about this argument,
    | >
    | > Practically as RAID5 uses XOR for checksum computation you do not have
    | > to read the whole stripe to recompute the checksum.
    | Ahh, good point. Ignore my argument - large stripes should work well. Mea
    | culpa, I forgot how simple the parity thing is, and that it is "local".
    | However, since seeking will be limited by the checksum drive anyway (for
    | writing), the advantages of large stripes in trying to keep the disks
    | independent aren't as one-sided.

    There is no "the" parity drive, remember the RAID-5 parity is
    distributed. A write takes two seeks, a read, a data write, and a parity
    write, but the parity isn't a bottleneck, and as noted above the size
    only need be the blocks containing the modified data.
    bill davidsen <>
    CTO, TMR Associates, Inc
    Doing interesting things with little computers since 1979.
    To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
    the body of a message to
    More majordomo info at
    Please read the FAQ at

     \ /
      Last update: 2005-03-22 13:59    [W:0.020 / U:27.996 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site