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    SubjectRe: [patch] fastcall-2.3.32-B6, SYSENTER/SYSEXIT support
    Pavel Machek wrote:
    > Well, read from cached file is _not_ meaningless, still Ingo seen
    > improvements on that.

    it only matters if you use very small chunks (for 1 byte reads/writes
    a 20+% difference is not uncommon), but already at 4096 bytes the
    improvement is in the noise (while it may be measurable, i doubt you'd
    notice it in rl). Where the lower read/write cost is more likely to
    matter is ipc/sockets/pipes etc (when you either pass things around
    or write small elements, like headers).

    > I think you should concentrate on read(), write() and select()
    > syscalls. Those are the ones done often.

    it's not about often used syscalls; it's about speeding up _all_
    of them. The only reason gettimeofday is singled out is because
    while you get a nice 31% improvement, you also get new infrastructure
    that lets you save another ~30%. [1] I can't think of other syscalls
    this is true for right now...

    [1] 1st number is measured difference, 2nd is estimation.

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      Last update: 2005-03-22 13:55    [W:0.022 / U:35.456 seconds]
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