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From: Ingo Molnar <mingo@kernel.org>
To: Peter Zijlstra <peterz@infradead.org>
Cc: Mike Galbraith <bitbucket@online.de>,
	Dave Chiluk <chiluk@canonical.com>,
	Ingo Molnar <mingo@redhat.com>,
	linux-kernel@vger.kernel.org
Subject: Re: Scheduler accounting inflated for io bound processes.
Date: Wed, 26 Jun 2013 17:50:48 +0200	[thread overview]
Message-ID: <20130626155048.GA7399@gmail.com> (raw)
In-Reply-To: <20130626104243.GE28407@twins.programming.kicks-ass.net>


* Peter Zijlstra <peterz@infradead.org> wrote:

> On Wed, Jun 26, 2013 at 11:37:13AM +0200, Ingo Molnar wrote:
> > Would be very nice to randomize the sampling rate, by randomizing the 
> > intervals within a 1% range or so - perf tooling will probably recognize 
> > the different weights.
> 
> You're suggesting adding noise to the regular kernel tick?

No, to the perf interval (which I assumed Mike was using to profile this?) 
- although slightly randomizing the kernel tick might make sense as well, 
especially if it's hrtimer driven and reprogrammed anyway.

I might have gotten it all wrong though ...

Thanks,

	Ingo

  reply	other threads:[~2013-06-26 15:50 UTC|newest]

Thread overview: 10+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2013-06-20 19:46 Scheduler accounting inflated for io bound processes Dave Chiluk
2013-06-25 16:01 ` Mike Galbraith
2013-06-25 17:48   ` Mike Galbraith
2013-06-26  9:37     ` Ingo Molnar
2013-06-26 10:42       ` Peter Zijlstra
2013-06-26 15:50         ` Ingo Molnar [this message]
2013-06-26 16:01           ` Mike Galbraith
2013-06-26 16:04           ` David Ahern
2013-06-26 16:10             ` Ingo Molnar
2013-06-26 16:13               ` David Ahern

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