lkml.org 
[lkml]   [2012]   [Jan]   [30]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    From
    SubjectRe: [PATCH v2] proc: speedup /proc/stat handling
    Date
    Eric Dumazet wrote, on 01/25/12 01:26:
    > Le mercredi 25 janvier 2012 à 09:18 +0900, KAMEZAWA Hiroyuki a écrit :
    >
    >> BTW, what is the reason of this change ?
    >>
    >>> - unsigned size = 4096 * (1 + num_possible_cpus() / 32);
    >>> + unsigned size = 1024 + 128 * num_possible_cpus();
    >>
    >> I think size of buffer is affected by the number of online cpus.
    >> (Maybe 128 is enough but please add comment why 128 ?)
    >>
    >
    > There is no change, as 4096/32 is 128 bytes per cpu.
    >

    Wrong math, only num_possible_cpus() is divided by 32. Thus,

    - unsigned size = 4096 * (1 + num_possible_cpus() / 32);
    + unsigned size = 4096 + 128 * num_possible_cpus();

    <snip>
    --
    Best regards,
    Jörg-Volker.

    --
    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: 2012-01-30 09:09    [W:0.023 / U:30.376 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site