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From: "Doug Smythies" <dsmythies@telus.net>
To: "'Rik van Riel'" <riel@surriel.com>
Cc: "'Linux PM'" <linux-pm@vger.kernel.org>,
        "'Frederic Weisbecker'" <fweisbec@gmail.com>,
        "'Thomas Gleixner'" <tglx@linutronix.de>,
        "'Paul McKenney'" <paulmck@linux.vnet.ibm.com>,
        "'Thomas Ilsche'" <thomas.ilsche@tu-dresden.de>,
        "'Aubrey Li'" <aubrey.li@linux.intel.com>,
        "'Mike Galbraith'" <mgalbraith@suse.de>,
        "'LKML'" <linux-kernel@vger.kernel.org>,
        "'Peter Zijlstra'" <peterz@infradead.org>,
        "'Rafael J. Wysocki'" <rjw@rjwysocki.net>,
        "Doug Smythies" <dsmythies@telus.net>
References: <4137867.C4jYrWdt8n@aspire.rjw.lan>  <20180314120450.GT4043@hirez.programming.kicks-ass.net> z38ge3YFh1Konz38iel45g
In-Reply-To: z38ge3YFh1Konz38iel45g
Subject: RE: [PATCH v2] cpuidle: poll_state: Add time limit to poll_idle()
Date: Thu, 22 Mar 2018 12:11:33 -0700
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On 2018.03.22 09:32 Rik van Riel wrote:
> 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.

I would very much like to be able to repeat your test results.
However, I am not sure what you mean by "memcache style workload".
Is there a test you can point me to? Say a Phoronix type test, for example.

All of my tests with the V3 of this patch have been fine.

... Doug