lkml.org 
[lkml]   [2002]   [Sep]   [18]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    Date
    From
    SubjectRe: [patch] lockless, scalable get_pid(), for_each_process() elimination, 2.5.35-BK

    On Wed, 18 Sep 2002, Rik van Riel wrote:
    >
    > On second thought ... yes there's a reason. Suppose you have
    > 100000 threads on your box already, how long is it going to
    > take to walk them all to figure out the pid distribution ?
    >
    > And are you willing to walk 100000 threads for every 16 pids allocated ?

    Give me a real-life case where that happens, and I might care. I dare you.

    The pid space is not a uniform distribution, which your made-up-example
    depends on. So you usually walk the 100000 threads _once_, and then you
    don't have to walk them again for quite a long time.

    And guys, if this is a performance problem for some extreme site, the fix
    is truly trivial:

    echo $((0x7fffffff)) > /proc/sys/max_pid

    and you're done.

    You're completely making up a problem that is not a problem in real life.
    Come back to me when the above doesn't work _in_practice_ and somebody is
    actually bitten, and maybe I'll care.

    Until then, all you're doing is mental masturbation.

    Linus

    -
    To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
    the body of a message to majordomo@vger.kernel.org
    More majordomo info at http://vger.kernel.org/majordomo-info.html
    Please read the FAQ at http://www.tux.org/lkml/

    \
     
     \ /
      Last update: 2005-03-22 13:15    [W:0.041 / U:0.388 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site