[lkml]   [2001]   [Jan]   [18]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
    SubjectRe: Is sendfile all that sexy?
    Roger Wolff writes:
    > I'd prefer an interface that says "copy this fd to that one, and
    > optimize that if you can".
    > For example, copying a file from one disk to another. I'm pretty sure
    > that some efficiency can be gained if you don't need to handle the
    > possibility of the userspace program accessing the data in between the
    > read and the write. Sure this may not qualify as a "trivial
    > optimization, that can be done with the existing infrastructure" right
    > now, but programs that want to indicate "kernel, please optimize this
    > if you can" can say so.

    Actually, this is a great example, because at one point I was working
    on a device interface which would offload all of the disk-disk copying
    overhead to the disks themselves, and not involve the CPU/RAM at all.

    I seem to recall that I2O promised something along these lines as well
    (i.e. direct device-device communication).

    Cheers, Andreas
    Andreas Dilger \ "If a man ate a pound of pasta and a pound of antipasto,
    \ would they cancel out, leaving him still hungry?" -- Dogbert
    To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
    the body of a message to
    Please read the FAQ at

     \ /
      Last update: 2005-03-22 13:25    [W:0.021 / U:5.144 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site