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Subject: Re: [patch] Re: PostgreSQL pgbench performance regression in
	2.6.23+
From: Peter Zijlstra <peterz@infradead.org>
To: Mike Galbraith <efault@gmx.de>
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Date: Sat, 07 Jun 2008 15:07:07 +0200
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On Sat, 2008-06-07 at 14:50 +0200, Mike Galbraith wrote:
> Since I tested mysql+oltp and made the dang pdf of the results, I may
> as well actually attach the thing <does that before continuing...>.
> 
> BTW, I have a question wrt avg_overlap.  When a wakeup cause the current
> task to begin sharing CPU with a freshly awakened task, the current task
> is tagged.. but the wakee isn't.  How come?  If one is sharing, so is
> the other.

avg_overlap is about measuring how long we'll run after waking someone
else. The other measure, how long our waker shares the cpu with us,
hasn't proven to be relevant so far.