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Subject: Re: [PATCH v2] cpuidle: poll_state: Add time limit to poll_idle()
From: Rik van Riel <riel@surriel.com>
To: Peter Zijlstra <peterz@infradead.org>,
        "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Linux PM <linux-pm@vger.kernel.org>,
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Date: Thu, 22 Mar 2018 12:32:18 -0400
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On Wed, 2018-03-14 at 13:04 +0100, Peter Zijlstra wrote:

> On x86 we don't have to use that time_check_counter thing,
> sched_clock()
> is really cheap, not sure if it makes sense on other platforms.

Are you sure? I saw a 5-10% increase in CPU use,
for a constant query rate to a memcache style
workload, with v3 of this patch.

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