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sched: Remove avg_overlap

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Both avg_overlap and avg_wakeup had an inherent problem in that their accuracy
was detrimentally affected by cross-cpu wakeups, this because we are missing
the necessary call to update_curr().  This can't be fixed without increasing
overhead in our already too fat fastpath.

Additionally, with recent load balancing changes making us prefer to place tasks
in an idle cache domain (which is good for compute bound loads), communicating
tasks suffer when a sync wakeup, which would enable affine placement, is turned
into a non-sync wakeup by SYNC_LESS.  With one task on the runqueue, wake_affine()
rejects the affine wakeup request, leaving the unfortunate where placed, taking
frequent cache misses.

Remove it, and recover some fastpath cycles.

Signed-off-by: Mike Galbraith <efault@gmx.de>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1268301121.6785.30.camel@marge.simson.net>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This commit is contained in:
Mike Galbraith
2010-03-11 17:15:51 +01:00
committed by Ingo Molnar
parent b42e0c41a4
commit e12f31d3e5
5 changed files with 0 additions and 71 deletions
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3
include/linux/sched.h
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@ -1180,9 +1180,6 @@ struct sched_entity {
u64 vruntime;
u64 prev_sum_exec_runtime;
u64 last_wakeup;
u64 avg_overlap;
u64 nr_migrations;
#ifdef CONFIG_SCHEDSTATS