From: Peter Zijlstra <peterz@infradead.org>
To: Quentin Perret <qperret@google.com>
Cc: Vincent Guittot <vincent.guittot@linaro.org>,
Dietmar Eggemann <dietmar.eggemann@arm.com>,
Ingo Molnar <mingo@kernel.org>,
Morten Rasmussen <morten.rasmussen@arm.com>,
Vincent Donnefort <vdonnefort@google.com>,
Patrick Bellasi <patrick.bellasi@matbug.net>,
Abhijeet Dharmapurikar <adharmap@quicinc.com>,
Jian-Min <Jian-Min.Liu@mediatek.com>,
Qais Yousef <qais.yousef@arm.com>,
linux-kernel@vger.kernel.org
Subject: Re: [RFC PATCH 1/1] sched/pelt: Introduce PELT multiplier
Date: Mon, 29 Aug 2022 16:34:39 +0200 [thread overview]
Message-ID: <YwzOf5WV5G8dQBGb@hirez.programming.kicks-ass.net> (raw)
In-Reply-To: <YwzL1eJUIReAEv0l@google.com>
On Mon, Aug 29, 2022 at 02:23:17PM +0000, Quentin Perret wrote:
> I'll let folks in CC comment about their use-case in more details, but
> there's definitely been an interest in tuning this thing at run-time
An interest and it making sense are two very distinct things that bear
no relation to one another in any way.
> FWIW. Typically a larger half-life will be fine with predictable
> workloads with little inputs from users (e.g. fullscreen video playback)
> while a lower one can be preferred in highly interactive cases (games,
As per always; consider the combined workload.
> ...). The transient state is fun to reason about, but it really
> shouldn't be too common AFAIK.
Once you give away control there is no taking it back, and userspace
*will* do stupid things and expect unicorns.
> With that said I'd quite like to see numbers to back that claim.
> Measuring power while running a video (for instance) with various HL
> values should help. And similarly it shouldn't be too hard to get
> performance numbers.
I'm thinking this all needs far more than mere numbers to justify.
next prev parent reply other threads:[~2022-08-29 14:35 UTC|newest]
Thread overview: 61+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-08-29 5:54 [RFC PATCH 0/1] sched/pelt: Change PELT halflife at runtime Dietmar Eggemann
2022-08-29 5:54 ` [RFC PATCH 1/1] sched/pelt: Introduce PELT multiplier Dietmar Eggemann
2022-08-29 8:08 ` Peter Zijlstra
2022-08-29 10:02 ` Peter Zijlstra
2022-08-29 10:13 ` Vincent Guittot
2022-08-29 14:23 ` Quentin Perret
2022-08-29 14:34 ` Peter Zijlstra [this message]
2022-08-29 15:31 ` Quentin Perret
2022-08-29 15:48 ` Quentin Perret
2022-09-02 7:53 ` Dietmar Eggemann
2022-09-02 8:45 ` Peter Zijlstra
2022-09-06 5:49 ` Vincent Guittot
2022-09-08 6:50 ` Dietmar Eggemann
2022-09-02 7:53 ` Dietmar Eggemann
2022-09-02 8:45 ` Peter Zijlstra
2022-09-20 14:07 ` [RFC PATCH 0/1] sched/pelt: Change PELT halflife at runtime Jian-Min Liu
2022-09-28 17:09 ` Dietmar Eggemann
2022-09-29 9:47 ` Peter Zijlstra
2022-09-29 11:07 ` Dietmar Eggemann
2022-09-29 11:10 ` Kajetan Puchalski
2022-09-29 11:21 ` Peter Zijlstra
2022-09-29 14:41 ` Kajetan Puchalski
2022-10-03 22:57 ` Wei Wang
2022-10-04 9:33 ` Dietmar Eggemann
2022-10-05 16:57 ` Wei Wang
2022-11-07 13:41 ` Peter Zijlstra
2022-11-08 19:48 ` Qais Yousef
2022-11-09 15:49 ` Peter Zijlstra
2022-11-10 13:25 ` Qais Yousef
2023-02-07 10:29 ` Dietmar Eggemann
2023-02-09 16:16 ` Vincent Guittot
2023-02-17 13:54 ` Dietmar Eggemann
2023-02-20 13:54 ` Vincent Guittot
2023-02-21 9:29 ` Vincent Guittot
2023-02-22 20:28 ` Dietmar Eggemann
2023-03-01 10:24 ` Vincent Guittot
2023-02-22 20:13 ` Dietmar Eggemann
2023-03-02 19:36 ` Dietmar Eggemann
2023-02-20 10:13 ` Peter Zijlstra
2023-02-20 13:39 ` Vincent Guittot
2023-02-23 15:37 ` Qais Yousef
2023-03-01 10:39 ` Vincent Guittot
2023-03-01 17:24 ` Qais Yousef
2023-03-02 8:00 ` Vincent Guittot
2023-03-02 19:39 ` Dietmar Eggemann
2023-03-06 19:11 ` Qais Yousef
2023-03-07 13:22 ` Vincent Guittot
2023-03-11 16:55 ` Qais Yousef
2023-03-23 16:29 ` Dietmar Eggemann
2023-04-03 14:45 ` Qais Yousef
2023-04-06 15:58 ` Dietmar Eggemann
2023-04-11 17:51 ` Qais Yousef
2022-11-09 15:18 ` Lukasz Luba
2022-11-10 11:16 ` Dietmar Eggemann
2022-11-10 13:05 ` Peter Zijlstra
2022-11-10 14:59 ` Dietmar Eggemann
2022-11-10 17:51 ` Peter Zijlstra
2022-11-30 18:14 ` Dietmar Eggemann
2022-12-01 13:37 ` Kajetan Puchalski
2022-11-10 12:45 ` Kajetan Puchalski
2022-11-07 9:41 ` Jian-Min Liu (劉建旻)
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