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    SubjectRe: [PATCH] allocation looping + kswapd CPU cycles
    On Tue, May 08 2001, Marcelo Tosatti wrote:
    > > The attached patch (against 2.4.5-pre1) fixes the looping symptom, by
    > > adding a counter and looping only twice for non-zero order allocations.
    >
    > Looks good. (actually Rik had a patch similar to this which fixed a real
    > case with cdda2wav just like you described)

    Not cdda2wav, I pressume, but the optimization discussed here before that
    wasn't really doable because of the vm behaviour when doing

    do
    try to alloc some amount of contiogous pages
    if (ok)
    break

    lower number of pages wanted
    while true

    CDROMREADAUDIO stopped doing this and fell back to single cdda frame
    size allocations because of these failures, even though it meant a huge
    decrease in speed. cdda2wav will ask for iirc 16 frames at the time, the
    current driver will try and to 8 first and then fall back to slower
    extraction if allocations fail.

    --
    Jens Axboe

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