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Subject: Re: [RFC PATCH v1 00/11] Create fast idle path for short idle periods
To: Thomas Gleixner <tglx@linutronix.de>
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Cc: Peter Zijlstra <peterz@infradead.org>, Andi Kleen <ak@linux.intel.com>,
        "Li, Aubrey" <aubrey.li@linux.intel.com>,
        Frederic Weisbecker <fweisbec@gmail.com>,
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        paulmck@linux.vnet.ibm.com, yang.zhang.wz@gmail.com, x86@kernel.org,
        linux-kernel@vger.kernel.org, daniel.lezcano@linaro.org
From: Arjan van de Ven <arjan@linux.intel.com>
Message-ID: <4fd3c407-2bb1-9b87-1cc4-b1c6012bf8a3@linux.intel.com>
Date: Mon, 17 Jul 2017 12:55:33 -0700
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On 7/17/2017 12:53 PM, Thomas Gleixner wrote:
> On Mon, 17 Jul 2017, Arjan van de Ven wrote:
>> On 7/17/2017 12:23 PM, Peter Zijlstra wrote:
>>> Of course, this all assumes a Gaussian distribution to begin with, if we
>>> get bimodal (or worse) distributions we can still get it wrong. To fix
>>> that, we'd need to do something better than what we currently have.
>>>
>>
>> fwiw some time ago I made a chart for predicted vs actual so you can sort
>> of judge the distribution of things visually
>
> Predicted by what?

this chart was with the current linux predictor

http://git.fenrus.org/tmp/timer.png is what you get if you JUST use the next timer ;-)
(which way back linux was doing)