From 15afe09bf496ae10c989e1a375a6b5da7bd3e16e Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Sat, 20 Sep 2008 23:38:02 +0200 Subject: sched: wakeup preempt when small overlap Lin Ming reported a 10% OLTP regression against 2.6.27-rc4. The difference seems to come from different preemption agressiveness, which affects the cache footprint of the workload and its effective cache trashing. Aggresively preempt a task if its avg overlap is very small, this should avoid the task going to sleep and find it still running when we schedule back to it - saving a wakeup. Reported-by: Lin Ming Signed-off-by: Peter Zijlstra Signed-off-by: Ingo Molnar --- kernel/sched_features.h | 1 + 1 file changed, 1 insertion(+) (limited to 'kernel/sched_features.h') diff --git a/kernel/sched_features.h b/kernel/sched_features.h index 9353ca78154e..bf027a7accf8 100644 --- a/kernel/sched_features.h +++ b/kernel/sched_features.h @@ -11,3 +11,4 @@ SCHED_FEAT(ASYM_GRAN, 1) SCHED_FEAT(LB_BIAS, 1) SCHED_FEAT(LB_WAKEUP_UPDATE, 1) SCHED_FEAT(ASYM_EFF_LOAD, 1) +SCHED_FEAT(WAKEUP_OVERLAP, 1) -- cgit v1.2.3-58-ga151