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    SubjectRe: Signal driven IO
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    > > Benchmark it for your application. For web and ftp traffic the I/O signals
    > > are a clear winner.
    >
    > A clear winner regardless of how many file desciptors are ready per "loop
    > pass"? Surely there has to be some number at which poll becomes superior.
    > Certainly with artificial cases where you overload the CPU and deliberately
    > hit multiple links at the same time.


    Web traffic is very large numbers of slow operations. Your ration of
    busy/queued is low. I'd agree there should be a point where you have a lot of
    busy operations but web/ftp isnt it.

    On a T1 you can expect to see 600 parallel connections. Each is averaging
    2 or 3 K a second with a typical 1500 byte MTU. So each FD wakes one or two
    times a second.

    So we have 1200 wakeup events per second over 600 handles. Even at 100polls/sec
    that means we get 12 positive handles and 588 overheads per poll. As it rises
    to the real world values its hits 1 and 599 overhead at 1000 polls/sec

    Alan



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