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    SubjectRe: [rfc] epoll interface change and glibc bits ...
    Davide Libenzi wrote:
    > And the lower size of the structure will help to reduce the amount of
    > memory transfered to userspace. I just saw that adding the extra "obj"
    > member lowered performance of about 15% with crazy tests like Ben's
    > pipetest. This because it creates, on my machine, more than 400000 events
    > per second, and saving memory bandwidth on such conditions is a must. With
    > the "more human" http test performance are about the same.

    I'd be quite surprised if 400,000 word/sec of memory bandwidth can
    explain a 15% time difference, especially considering all the other
    things that are done to communicate over a pipe (wakeups etc).

    Btw, I have seen variations of that magnitude in other network tests
    that I've done that _appear_ to be explained by small changes to the
    code like that, but the next day or week the variation stops
    correlating with the change. Page colouring affecting benchmarks
    again?

    -- Jamie
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