From: Daniel Lezcano <daniel.lezcano@linaro.org>
To: Vincent Guittot <vincent.guittot@linaro.org>
Cc: linux-kernel <linux-kernel@vger.kernel.org>,
Ingo Molnar <mingo@elte.hu>,
Peter Zijlstra <peterz@infradead.org>,
"rjw@rjwysocki.net" <rjw@rjwysocki.net>,
Nicolas Pitre <nicolas.pitre@linaro.org>,
"linux-pm@vger.kernel.org" <linux-pm@vger.kernel.org>,
Alex Shi <alex.shi@linaro.org>,
Morten Rasmussen <morten.rasmussen@arm.com>
Subject: Re: [RFC PATCHC 0/3] sched/idle : find the idlest cpu with cpuidle info
Date: Tue, 01 Apr 2014 09:43:57 +0200 [thread overview]
Message-ID: <533A6E3D.4040002@linaro.org> (raw)
In-Reply-To: <CAKfTPtBiFUM90igrhz=VnvSkt9MQ2E-xxnzDf=wSKdK+qA4EQA@mail.gmail.com>
On 04/01/2014 09:16 AM, Vincent Guittot wrote:
> On 31 March 2014 17:55, Daniel Lezcano <daniel.lezcano@linaro.org> wrote:
>> On 03/31/2014 03:52 PM, Vincent Guittot wrote:
>>>
>>> On 28 March 2014 13:29, Daniel Lezcano <daniel.lezcano@linaro.org> wrote:
>>>>
>>>> The following patchset provides an interaction between cpuidle and the
>>>> scheduler.
>>>>
>>>> The first patch encapsulate the needed information for the scheduler in a
>>>> separate cpuidle structure. The second one stores the pointer to this
>>>> structure
>>>> when entering idle. The third one, use this information to take the
>>>> decision to
>>>> find the idlest cpu.
>>>>
>>>> After some basic testing with hackbench, it appears there is an
>>>> improvement for
>>>> the performances (small) and for the duration of the idle states (which
>>>> provides
>>>> a better power saving).
>>>>
>>>> The measurement has been done with the 'idlestat' tool previously posted
>>>> in this
>>>> mailing list.
>>>>
>>>> So the benefit is good for both sides performance and power saving.
>>>
>>>
>>> Hi Daniel,
>>>
>>> I have looked at your results and i'm a bit surprised that you have so
>>> much time in C-state with a test that involved 400 tasks on a dual
>>> cores HT system. You shouldn't have any CPUs in idle state when
>>> running hackbench; the total time of core0state in C7-IVB is
>>> 87932131.00(us), which is quite huge for a bench that runs 44sec. Or
>>> i'm doing something wrong in the interpretation of the results ?
>>
>>
>> No, actually I mixed the output of hackbench without being run with idlestat
>> or with idlestat.
>>
>> The hackbench's results below are without idlestat.
>>
>> The idlestat results are consistent and effectively it adds a non
>> negligeable overhead as it impacts the hackbench results.
>>
>> So to summarize, hackbench has been run 4 times.
>>
>> 1, 2 : without idlestat, with and without the patchset - hackbench results
>> ~42 secs
>>
>> 3, 4 : with idlestat, with and without the patchset - hackbench results ~87
>> secs
>>
>> At the first the glance, the results are consistent but I will double check
>> them.
>>
>> Do you have a suggestion for a benchmarking program ?
>
> We are working on a bench which can generate middle load pattern with
> idle CPUs but it's not available yet. In the mean time, one bench that
> plays with idle time is cyclictest, it will not give you performance
> results but only scheduling latency which might be what you are
> looking for.
Yeah, thanks. I believe I know what is in the rt-tests package :)
What I meant is what kind of values would you like to see with this
patchset ?
>>>> The select_idle_sibling could be also improved in the same way.
>>>>
>>>> ====================== test with hackbench 3.14-rc8
>>>> =========================
>>>>
>>>> /usr/bin/hackbench -l 10000 -s 4096
>>>>
>>>> Running in process mode with 10 groups using 40 file descriptors each (==
>>>> 400 tasks)
>>>> Each sender will pass 10000 messages of 4096 bytes
>>>>
>>>> Time: 44.433
>>>>
>>>> Total trace buffer: 1846688 kB
>>>> clusterA@state hits total(us) avg(us) min(us) max(us)
>>>> POLL 0 0.00 0.00 0.00 0.00
>>>> C1-IVB 0 0.00 0.00 0.00 0.00
>>>> C1E-VB 0 0.00 0.00 0.00 0.00
>>>> C3-IVB 0 0.00 0.00 0.00 0.00
>>>> C6-IVB 0 0.00 0.00 0.00 0.00
>>>> C7-IVB 0 0.00 0.00 0.00 0.00
>>>> core0@state hits total(us) avg(us) min(us) max(us)
>>>> POLL 0 0.00 0.00 0.00 0.00
>>>> C1-IVB 0 0.00 0.00 0.00 0.00
>>>> C1E-IVB 0 0.00 0.00 0.00 0.00
>>>> C3-IVB 0 0.00 0.00 0.00 0.00
>>>> C6-IVB 0 0.00 0.00 0.00 0.00
>>>> C7-IVB 1396 87932131.00 62988.63 0.00
>>>> 320146.00
>>>> cpu0@state hits total(us) avg(us) min(us) max(us)
>>>> POLL 0 0.00 0.00 0.00 0.00
>>>> C1-IVB 1 14.00 14.00 14.00 14.00
>>>> C1E-VB 0 0.00 0.00 0.00 0.00
>>>> C3-IVB 1 262.00 262.00 262.00 262.00
>>>> C6-IVB 0 0.00 0.00 0.00 0.00
>>>> C7-IVB 1180 87938177.00 74523.88 1.00
>>>> 320147.00
>>>> 1701 0 0.00 0.00 0.00 0.00
>>>> 1700 0 0.00 0.00 0.00 0.00
>>>> 1600 0 0.00 0.00 0.00 0.00
>>>> 1500 0 0.00 0.00 0.00 0.00
>>>> 1400 0 0.00 0.00 0.00 0.00
>>>> 1300 0 0.00 0.00 0.00 0.00
>>>> 1200 0 0.00 0.00 0.00 0.00
>>>> 1100 0 0.00 0.00 0.00 0.00
>>>> 1000 0 0.00 0.00 0.00 0.00
>>>> 900 0 0.00 0.00 0.00 0.00
>>>> 800 0 0.00 0.00 0.00 0.00
>>>> 782 0 0.00 0.00 0.00 0.00
>>>> cpu0 wakeups name count
>>>> irq009 acpi 1
>>>> cpu1@state hits total(us) avg(us) min(us) max(us)
>>>> POLL 0 0.00 0.00 0.00 0.00
>>>> C1-IVB 0 0.00 0.00 0.00 0.00
>>>> C1E-VB 0 0.00 0.00 0.00 0.00
>>>> C3-IVB 0 0.00 0.00 0.00 0.00
>>>> C6-IVB 0 0.00 0.00 0.00 0.00
>>>> C7-IVB 475 87941356.00 185139.70 322.00
>>>> 1500690.00
>>>> 1701 0 0.00 0.00 0.00 0.00
>>>> 1700 0 0.00 0.00 0.00 0.00
>>>> 1600 0 0.00 0.00 0.00 0.00
>>>> 1500 0 0.00 0.00 0.00 0.00
>>>> 1400 0 0.00 0.00 0.00 0.00
>>>> 1300 0 0.00 0.00 0.00 0.00
>>>> 1200 0 0.00 0.00 0.00 0.00
>>>> 1100 0 0.00 0.00 0.00 0.00
>>>> 1000 0 0.00 0.00 0.00 0.00
>>>> 900 0 0.00 0.00 0.00 0.00
>>>> 800 0 0.00 0.00 0.00 0.00
>>>> 782 0 0.00 0.00 0.00 0.00
>>>> cpu1 wakeups name count
>>>> irq009 acpi 3
>>>> core1@state hits total(us) avg(us) min(us) max(us)
>>>> POLL 0 0.00 0.00 0.00 0.00
>>>> C1-IVB 0 0.00 0.00 0.00 0.00
>>>> C1E-IVB 0 0.00 0.00 0.00 0.00
>>>> C3-IVB 0 0.00 0.00 0.00 0.00
>>>> C6-IVB 0 0.00 0.00 0.00 0.00
>>>> C7-IVB 0 0.00 0.00 0.00 0.00
>>>> cpu2@state hits total(us) avg(us) min(us) max(us)
>>>> POLL 0 0.00 0.00 0.00 0.00
>>>> C1-IVB 11 288157.00 26196.09 16.00
>>>> 200060.00
>>>> C1E-VB 6 221601.00 36933.50 79.00
>>>> 200066.00
>>>> C3-IVB 0 0.00 0.00 0.00 0.00
>>>> C6-IVB 0 0.00 0.00 0.00 0.00
>>>> C7-IVB 950 87417466.00 92018.39 19.00
>>>> 200074.00
>>>> 1701 0 0.00 0.00 0.00 0.00
>>>> 1700 0 0.00 0.00 0.00 0.00
>>>> 1600 0 0.00 0.00 0.00 0.00
>>>> 1500 2 34.00 17.00 11.00 23.00
>>>> 1400 0 0.00 0.00 0.00 0.00
>>>> 1300 0 0.00 0.00 0.00 0.00
>>>> 1200 0 0.00 0.00 0.00 0.00
>>>> 1100 0 0.00 0.00 0.00 0.00
>>>> 1000 0 0.00 0.00 0.00 0.00
>>>> 900 0 0.00 0.00 0.00 0.00
>>>> 800 0 0.00 0.00 0.00 0.00
>>>> 782 745 18800.00 25.23 2.00 156.00
>>>> cpu2 wakeups name count
>>>> irq019 ahci 50
>>>> irq009 acpi 17
>>>> cpu3@state hits total(us) avg(us) min(us) max(us)
>>>> POLL 0 0.00 0.00 0.00 0.00
>>>> C1-IVB 0 0.00 0.00 0.00 0.00
>>>> C1E-VB 0 0.00 0.00 0.00 0.00
>>>> C3-IVB 0 0.00 0.00 0.00 0.00
>>>> C6-IVB 0 0.00 0.00 0.00 0.00
>>>> C7-IVB 0 0.00 0.00 0.00 0.00
>>>> 1701 0 0.00 0.00 0.00 0.00
>>>> 1700 0 0.00 0.00 0.00 0.00
>>>> 1600 0 0.00 0.00 0.00 0.00
>>>> 1500 0 0.00 0.00 0.00 0.00
>>>> 1400 0 0.00 0.00 0.00 0.00
>>>> 1300 0 0.00 0.00 0.00 0.00
>>>> 1200 0 0.00 0.00 0.00 0.00
>>>> 1100 0 0.00 0.00 0.00 0.00
>>>> 1000 0 0.00 0.00 0.00 0.00
>>>> 900 0 0.00 0.00 0.00 0.00
>>>> 800 0 0.00 0.00 0.00 0.00
>>>> 782 0 0.00 0.00 0.00 0.00
>>>> cpu3 wakeups name count
>>>>
>>>> ================ test with hackbench 3.14-rc8 + patchset
>>>> ====================
>>>>
>>>> /usr/bin/hackbench -l 10000 -s 4096
>>>>
>>>> Running in process mode with 10 groups using 40 file descriptors each (==
>>>> 400 tasks)
>>>> Each sender will pass 10000 messages of 4096 bytes
>>>>
>>>> Time: 42.179
>>>>
>>>> Total trace buffer: 1846688 kB
>>>> clusterA@state hits total(us) avg(us) min(us) max(us)
>>>> POLL 0 0.00 0.00 0.00 0.00
>>>> C1-IVB 0 0.00 0.00 0.00 0.00
>>>> C1E-VB 0 0.00 0.00 0.00 0.00
>>>> C3-IVB 0 0.00 0.00 0.00 0.00
>>>> C6-IVB 0 0.00 0.00 0.00 0.00
>>>> C7-IVB 0 0.00 0.00 0.00 0.00
>>>> core0@state hits total(us) avg(us) min(us) max(us)
>>>> POLL 0 0.00 0.00 0.00 0.00
>>>> C1-IVB 0 0.00 0.00 0.00 0.00
>>>> C1E-IVB 0 0.00 0.00 0.00 0.00
>>>> C3-IVB 0 0.00 0.00 0.00 0.00
>>>> C6-IVB 0 0.00 0.00 0.00 0.00
>>>> C7-IVB 880 89157590.00 101315.44 0.00
>>>> 400184.00
>>>> cpu0@state hits total(us) avg(us) min(us) max(us)
>>>> POLL 0 0.00 0.00 0.00 0.00
>>>> C1-IVB 0 0.00 0.00 0.00 0.00
>>>> C1E-VB 1 233.00 233.00 233.00 233.00
>>>> C3-IVB 1 260.00 260.00 260.00 260.00
>>>> C6-IVB 0 0.00 0.00 0.00 0.00
>>>> C7-IVB 700 89162006.00 127374.29 182.00
>>>> 400187.00
>>>> 1701 0 0.00 0.00 0.00 0.00
>>>> 1700 0 0.00 0.00 0.00 0.00
>>>> 1600 0 0.00 0.00 0.00 0.00
>>>> 1500 0 0.00 0.00 0.00 0.00
>>>> 1400 0 0.00 0.00 0.00 0.00
>>>> 1300 0 0.00 0.00 0.00 0.00
>>>> 1200 0 0.00 0.00 0.00 0.00
>>>> 1100 0 0.00 0.00 0.00 0.00
>>>> 1000 0 0.00 0.00 0.00 0.00
>>>> 900 0 0.00 0.00 0.00 0.00
>>>> 800 0 0.00 0.00 0.00 0.00
>>>> 782 0 0.00 0.00 0.00 0.00
>>>> cpu0 wakeups name count
>>>> irq009 acpi 2
>>>> cpu1@state hits total(us) avg(us) min(us) max(us)
>>>> POLL 0 0.00 0.00 0.00 0.00
>>>> C1-IVB 0 0.00 0.00 0.00 0.00
>>>> C1E-VB 0 0.00 0.00 0.00 0.00
>>>> C3-IVB 0 0.00 0.00 0.00 0.00
>>>> C6-IVB 0 0.00 0.00 0.00 0.00
>>>> C7-IVB 334 89164805.00 266960.49 1.00
>>>> 1500677.00
>>>> 1701 0 0.00 0.00 0.00 0.00
>>>> 1700 0 0.00 0.00 0.00 0.00
>>>> 1600 0 0.00 0.00 0.00 0.00
>>>> 1500 0 0.00 0.00 0.00 0.00
>>>> 1400 0 0.00 0.00 0.00 0.00
>>>> 1300 0 0.00 0.00 0.00 0.00
>>>> 1200 0 0.00 0.00 0.00 0.00
>>>> 1100 0 0.00 0.00 0.00 0.00
>>>> 1000 0 0.00 0.00 0.00 0.00
>>>> 900 0 0.00 0.00 0.00 0.00
>>>> 800 0 0.00 0.00 0.00 0.00
>>>> 782 0 0.00 0.00 0.00 0.00
>>>> cpu1 wakeups name count
>>>> irq009 acpi 6
>>>> core1@state hits total(us) avg(us) min(us) max(us)
>>>> POLL 0 0.00 0.00 0.00 0.00
>>>> C1-IVB 0 0.00 0.00 0.00 0.00
>>>> C1E-IVB 0 0.00 0.00 0.00 0.00
>>>> C3-IVB 0 0.00 0.00 0.00 0.00
>>>> C6-IVB 0 0.00 0.00 0.00 0.00
>>>> C7-IVB 0 0.00 0.00 0.00 0.00
>>>> cpu2@state hits total(us) avg(us) min(us) max(us)
>>>> POLL 0 0.00 0.00 0.00 0.00
>>>> C1-IVB 19 2169047.00 114160.37 18.00
>>>> 999129.00
>>>> C1E-IB 0 0.00 0.00 0.00 0.00
>>>> C3-IVB 0 0.00 0.00 0.00 0.00
>>>> C6-IVB 0 0.00 0.00 0.00 0.00
>>>> C7-IVB 376 86993307.00 231365.18 20.00
>>>> 1500682.00
>>>> 1701 0 0.00 0.00 0.00 0.00
>>>> 1700 0 0.00 0.00 0.00 0.00
>>>> 1600 0 0.00 0.00 0.00 0.00
>>>> 1500 0 0.00 0.00 0.00 0.00
>>>> 1400 0 0.00 0.00 0.00 0.00
>>>> 1300 0 0.00 0.00 0.00 0.00
>>>> 1200 0 0.00 0.00 0.00 0.00
>>>> 1100 0 0.00 0.00 0.00 0.00
>>>> 1000 0 0.00 0.00 0.00 0.00
>>>> 900 0 0.00 0.00 0.00 0.00
>>>> 800 0 0.00 0.00 0.00 0.00
>>>> 782 0 0.00 0.00 0.00 0.00
>>>> cpu2 wakeups name count
>>>> irq009 acpi 32
>>>> irq019 ahci 45
>>>> cpu3@state hits total(us) avg(us) min(us) max(us)
>>>> POLL 0 0.00 0.00 0.00 0.00
>>>> C1-IVB 0 0.00 0.00 0.00 0.00
>>>> C1E-VB 0 0.00 0.00 0.00 0.00
>>>> C3-IVB 0 0.00 0.00 0.00 0.00
>>>> C6-IVB 0 0.00 0.00 0.00 0.00
>>>> C7-IVB 0 0.00 0.00 0.00 0.00
>>>> 1701 0 0.00 0.00 0.00 0.00
>>>> 1700 0 0.00 0.00 0.00 0.00
>>>> 1600 0 0.00 0.00 0.00 0.00
>>>> 1500 0 0.00 0.00 0.00 0.00
>>>> 1400 0 0.00 0.00 0.00 0.00
>>>> 1300 0 0.00 0.00 0.00 0.00
>>>> 1200 0 0.00 0.00 0.00 0.00
>>>> 1100 0 0.00 0.00 0.00 0.00
>>>> 1000 0 0.00 0.00 0.00 0.00
>>>> 900 0 0.00 0.00 0.00 0.00
>>>> 800 0 0.00 0.00 0.00 0.00
>>>> 782 0 0.00 0.00 0.00 0.00
>>>> cpu3 wakeups name count
>>>>
>>>>
>>>> Daniel Lezcano (3):
>>>> cpuidle: encapsulate power info in a separate structure
>>>> idle: store the idle state the cpu is
>>>> sched/fair: use the idle state info to choose the idlest cpu
>>>>
>>>> arch/arm/include/asm/cpuidle.h | 6 +-
>>>> arch/arm/mach-exynos/cpuidle.c | 4 +-
>>>> drivers/acpi/processor_idle.c | 4 +-
>>>> drivers/base/power/domain.c | 6 +-
>>>> drivers/cpuidle/cpuidle-at91.c | 4 +-
>>>> drivers/cpuidle/cpuidle-big_little.c | 9 +--
>>>> drivers/cpuidle/cpuidle-calxeda.c | 6 +-
>>>> drivers/cpuidle/cpuidle-kirkwood.c | 4 +-
>>>> drivers/cpuidle/cpuidle-powernv.c | 8 +--
>>>> drivers/cpuidle/cpuidle-pseries.c | 12 ++--
>>>> drivers/cpuidle/cpuidle-ux500.c | 14 ++---
>>>> drivers/cpuidle/cpuidle-zynq.c | 4 +-
>>>> drivers/cpuidle/driver.c | 6 +-
>>>> drivers/cpuidle/governors/ladder.c | 14 +++--
>>>> drivers/cpuidle/governors/menu.c | 8 +--
>>>> drivers/cpuidle/sysfs.c | 2 +-
>>>> drivers/idle/intel_idle.c | 112
>>>> +++++++++++++++++-----------------
>>>> include/linux/cpuidle.h | 10 ++-
>>>> kernel/sched/fair.c | 46 ++++++++++++--
>>>> kernel/sched/idle.c | 17 +++++-
>>>> kernel/sched/sched.h | 5 ++
>>>> 21 files changed, 180 insertions(+), 121 deletions(-)
>>>>
>>>> --
>>>> 1.7.9.5
>>>>
>>
>>
>> --
>> <http://www.linaro.org/> Linaro.org │ Open source software for ARM SoCs
>>
>> Follow Linaro: <http://www.facebook.com/pages/Linaro> Facebook |
>> <http://twitter.com/#!/linaroorg> Twitter |
>> <http://www.linaro.org/linaro-blog/> Blog
>>
--
<http://www.linaro.org/> Linaro.org │ Open source software for ARM SoCs
Follow Linaro: <http://www.facebook.com/pages/Linaro> Facebook |
<http://twitter.com/#!/linaroorg> Twitter |
<http://www.linaro.org/linaro-blog/> Blog
next prev parent reply other threads:[~2014-04-01 7:43 UTC|newest]
Thread overview: 47+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-03-28 12:29 [RFC PATCHC 0/3] sched/idle : find the idlest cpu with cpuidle info Daniel Lezcano
2014-03-28 12:29 ` [RFC PATCHC 1/3] cpuidle: encapsulate power info in a separate structure Daniel Lezcano
2014-03-28 18:17 ` Nicolas Pitre
2014-03-28 20:42 ` Daniel Lezcano
2014-03-29 0:00 ` Nicolas Pitre
2014-03-28 12:29 ` [RFC PATCHC 2/3] idle: store the idle state the cpu is Daniel Lezcano
2014-04-15 12:43 ` Peter Zijlstra
2014-04-15 12:44 ` Peter Zijlstra
2014-04-15 14:17 ` Daniel Lezcano
2014-04-15 14:33 ` Peter Zijlstra
2014-04-15 14:39 ` Daniel Lezcano
2014-03-28 12:29 ` [RFC PATCHC 3/3] sched/fair: use the idle state info to choose the idlest cpu Daniel Lezcano
2014-04-02 3:05 ` Nicolas Pitre
2014-04-04 11:57 ` Rafael J. Wysocki
2014-04-04 16:56 ` Nicolas Pitre
2014-04-05 2:01 ` Rafael J. Wysocki
2014-04-17 13:53 ` Daniel Lezcano
2014-04-17 14:47 ` Peter Zijlstra
2014-04-17 15:03 ` Daniel Lezcano
2014-04-18 8:09 ` Ingo Molnar
2014-04-18 8:36 ` Daniel Lezcano
2014-04-17 15:53 ` Nicolas Pitre
2014-04-17 16:05 ` Daniel Lezcano
2014-04-17 16:21 ` Nicolas Pitre
2014-04-18 9:38 ` Peter Zijlstra
2014-04-18 12:13 ` Daniel Lezcano
2014-04-18 12:53 ` Peter Zijlstra
2014-04-18 13:04 ` Daniel Lezcano
2014-04-18 16:00 ` Nicolas Pitre
2014-04-15 13:03 ` Peter Zijlstra
2014-03-31 13:52 ` [RFC PATCHC 0/3] sched/idle : find the idlest cpu with cpuidle info Vincent Guittot
2014-03-31 15:55 ` Daniel Lezcano
2014-04-01 7:16 ` Vincent Guittot
2014-04-01 7:43 ` Daniel Lezcano [this message]
2014-04-01 9:05 ` Vincent Guittot
2014-04-15 13:13 ` Peter Zijlstra
2014-04-01 23:01 ` Rafael J. Wysocki
2014-04-02 3:14 ` Nicolas Pitre
2014-04-04 11:43 ` Rafael J. Wysocki
2014-04-15 13:17 ` Peter Zijlstra
2014-04-15 13:25 ` Peter Zijlstra
2014-04-15 15:27 ` Nicolas Pitre
2014-04-15 15:33 ` Rafael J. Wysocki
2014-04-02 8:26 ` Daniel Lezcano
2014-04-04 11:23 ` Rafael J. Wysocki
2014-04-04 6:29 ` Len Brown
2014-04-04 8:16 ` Daniel Lezcano
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