[lkml]   [2006]   [Jun]   [2]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
SubjectRe: [PATCH RFC] smt nice introduces significant lock contention
On Friday 02 June 2006 18:28, Nick Piggin wrote:
> Con Kolivas wrote:
> > On Friday 02 June 2006 17:53, Nick Piggin wrote:
> >>This is a small micro-optimisation / cleanup we can do after
> >>smtnice gets converted to use trylocks. Might result in a little
> >>less cacheline footprint in some cases.
> >
> > It's only dependent_sleeper that is being converted in these patches. The
> > wake_sleeping_dependent component still locks all runqueues and needs to
> Oh I missed that.
> > succeed in order to ensure a task doesn't keep sleeping indefinitely.
> > That
> Let's make it use trylocks as well. wake_priority_sleeper should ensure
> things don't sleep forever I think? We should be optimising for the most
> common case, and in many workloads, the runqueue does go idle frequently.

wake_priority_sleeper is only called per tick which can be 10ms at 100HZ. I
don't think that's fast enough. It could even be possible for a lower
priority task to always just miss the wakeup if it's (very) unlucky.

To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to
More majordomo info at
Please read the FAQ at

 \ /
  Last update: 2006-06-02 12:22    [W:0.196 / U:1.140 seconds]
©2003-2017 Jasper Spaans. hosted at Digital OceanAdvertise on this site