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Subject: Re: [PATCH v3 09/22] sched: compute runnable load avg in cpu_load
 and cpu_avg_load_per_task
From: Mike Galbraith <efault@gmx.de>
To: Alex Shi <alex.shi@intel.com>
Cc: Paul Turner <pjt@google.com>, Ingo Molnar <mingo@redhat.com>,
        Peter Zijlstra <peterz@infradead.org>,
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Date: Tue, 22 Jan 2013 10:52:18 +0100
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On Tue, 2013-01-22 at 15:50 +0800, Alex Shi wrote:

> Thanks for your suggestions and example, Mike!
> I just can't understand the your last words here, Sorry. what the
> detailed concern of you on 'both performance profiles with either
> metric'? Could you like to give your preferred solutions?

Hm.. I'll try rephrasing.  Any power saving gain will of necessity be
paid for in latency currency.  I don't have a solution other than make a
button, let the user decide whether history influences fast path task
placement or not.  Any other decision maker will get it wrong.

-Mike