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    SubjectRe: [PATCH 2/4]: powerpc/cell spidernet low watermark patch.
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    On Thu, Aug 17, 2006 at 01:43:40AM +0200, Benjamin Herrenschmidt wrote:
    >
    > Sounds good (without actually looking at the code though :), that was a
    > long required improvement to that driver. Also, we should probably look
    > into using NAPI polling for tx completion queue as well, no ?

    Just for a lark, I tried using NAPI polling, while disabling all TX
    interrupts. Performance was a disaster: 8Mbits/sec, fom which I conclude
    that the tcp ack packets do not flow back fast enough to allw reliance
    on NAPI polling for transmit.

    I was able to get as high as 960 Mbits/sec in unusal circumstances,
    at 100% cpu usage. Oprofile indicates that the next major improvement
    would be to add scatter/gather, which I'll take a shot at next week,
    if I don't get interrupted. However, I'm getting interrupted a lot these
    days.

    --linas
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