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Subject: Re: [patch] Re: PostgreSQL pgbench performance regression in
	2.6.23+
From: Mike Galbraith <efault@gmx.de>
To: Greg Smith <gsmith@gregsmith.com>
Cc: Ingo Molnar <mingo@elte.hu>, Peter Zijlstra <peterz@infradead.org>,
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On Tue, 2008-05-27 at 10:20 +0200, Mike Galbraith wrote:

> Hm, pbench's extreme dislike of preemption, and the starvation testcase
> I sent earlier having an absolute requirement of preemption kinda argues
> that some knobs and dials should be per task or task group (or, or... or
> scheduler should be all knowing all seeing;) 

(to somewhat solidify the random thought i'm sharing...)

Perhaps a SCHED_PREEMPT class so such things can co-exist:

SCHED_BATCH == I never preempt.
SCHED_NORMAL == I preempt sometimes.
SCHED_PREEMPT == I always preempt my waker.

(end of random synaptic firing;)

	-Mike