lkml.org 
[lkml]   [2006]   [Jun]   [2]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    From
    SubjectRe: [PATCH RFC] smt nice introduces significant lock contention
    Date
    On Friday 02 June 2006 19:31, Chen, Kenneth W wrote:
    > Con Kolivas wrote on Friday, June 02, 2006 2:25 AM
    >
    > > On Friday 02 June 2006 19:17, Chen, Kenneth W wrote:
    > > > What about the part in dependent_sleeper() being so bully and actively
    > > > resched other low priority sibling tasks? I think it would be better
    > > > to just let the tasks running on sibling CPU to finish its current time
    > > > slice and then let the backoff logic to kick in.
    > >
    > > That would defeat the purpose of smt nice if the higher priority task
    > > starts after the lower priority task is running on its sibling cpu.
    >
    > But only for the duration of lower priority tasks' time slice. When lower
    > priority tasks time slice is used up, a resched is force from
    > scheduler_tick(), isn't it? And at that time, it is delayed to run because
    > of smt_nice. You are saying user can't tolerate that short period of time
    > that CPU resource is shared? It's hard to believe.

    nice -20 vs nice 0 is 800ms vs 100ms. That's a long time to me.

    --
    -ck
    -
    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: 2006-06-02 11:37    [W:0.022 / U:1.404 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site