lkml.org 
[lkml]   [2003]   [Aug]   [23]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    From
    SubjectRe: [PATCH]O18.1int
    Date
    On Saturday 23 August 2003 07:55, Con Kolivas wrote:
    > Some high credit tasks were being missed due to their prolonged cpu burn at
    > startup flagging them as low credit tasks.
    >
    > Low credit tasks can now recover to become high credit.
    >
    > Con

    Hi Con!

    First of all... Your interactive scheduler work is GREAT! I really like it...!

    Now I tried to unterstand what exacly the latest patch does, and as far as I
    can see the first and the third hunk just delete respectively expand the
    macro VARYING_CREDIT(p). But the second hunk helps processes to get some
    interactive_credit until they become a HIGH_CREDIT task. This looks
    reasonable to me...

    So, now I wanted to know how a task may lose its interactive_credit again...
    The only code I saw doing this is exaclty the third hunk of your patch. But
    if a process is a HIGH_CREDIT task it can never lose its interactive_credit
    again. Is that intented?

    I think the third hunk should look like following:
    @@ -1548,7 +1545,7 @@ switch_tasks:
    prev->sleep_avg -= run_time;
    if ((long)prev->sleep_avg <= 0){
    prev->sleep_avg = 0;
    - prev->interactive_credit -= VARYING_CREDIT(prev);
    + prev->interactive_credit -= !(LOW_CREDIT(prev));
    }
    prev->timestamp = now;

    As an additional idea I think interactive_credit should be allowed to be a bit
    bigger than MAX_SLEEP_AVG and a bit lower than -MAX_SLEEP_AVG. This would
    make LOW_CREDIT processes stay LOW_CREDIT even if they do some sleep and
    HIGH_CREDIT processes star HIGH_CREDIT even if they do some computing...

    But of course I may completely miss something...

    Thomas
    -
    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 13:48    [W:2.846 / U:0.144 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site