From: Christian Loehle <christian.loehle@arm.com>
To: Sergey Senozhatsky <senozhatsky@chromium.org>,
Vincent Guittot <vincent.guittot@linaro.org>,
"Rafael J. Wysocki" <rafael@kernel.org>
Cc: Viresh Kumar <viresh.kumar@linaro.org>,
Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
Yu-Che Cheng <giver@google.com>, Tomasz Figa <tfiga@chromium.org>,
stable@vger.kernel.org, linux-pm@vger.kernel.org,
linux-kernel@vger.kernel.org, Lukasz Luba <lukasz.luba@arm.com>,
Dietmar Eggemann <dietmar.eggemann@arm.com>
Subject: Re: stable 6.6: commit "sched/cpufreq: Rework schedutil governor performance estimation' causes a regression
Date: Thu, 20 Nov 2025 10:15:11 +0000 [thread overview]
Message-ID: <86d759a5-9a96-49ff-9f75-8b56e2626d65@arm.com> (raw)
In-Reply-To: <q2dp7jlblofwkmkufjdysgu2ggv6g4cvhkah3trr5wamxymngm@p2mn4r7vyo77>
On 11/20/25 04:45, Sergey Senozhatsky wrote:
> Hi,
>
> We are observing a performance regression on one of our arm64 boards.
> We tracked it down to the linux-6.6.y commit ada8d7fa0ad4 ("sched/cpufreq:
> Rework schedutil governor performance estimation").
>
> UI speedometer benchmark:
> w/commit: 395 +/-38
> w/o commit: 439 +/-14
>
Hi Sergey,
Would be nice to get some details. What board? What do the OPPs look like?
Does this system use uclamp during the benchmark? How?
Given how large the stddev given by speedometer (version 3?) itself is, can we get the
stats of a few runs?
Maybe traces of cpu_frequency for both w/ and w/o?
next prev parent reply other threads:[~2025-11-20 10:15 UTC|newest]
Thread overview: 19+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-11-20 4:45 stable 6.6: commit "sched/cpufreq: Rework schedutil governor performance estimation' causes a regression Sergey Senozhatsky
2025-11-20 10:15 ` Christian Loehle [this message]
2025-11-21 3:55 ` Sergey Senozhatsky
2025-11-21 7:02 ` Sergey Senozhatsky
2025-11-21 7:22 ` Vincent Guittot
2025-11-21 13:59 ` Vincent Guittot
2025-11-21 15:53 ` Yu-Che Cheng
[not found] ` <CAKchOA03GKXMUbfVvEXtyp3=-t0mWOzQVHNkB6F9QsMfTzCofA@mail.gmail.com>
2025-11-21 16:35 ` Christian Loehle
2025-11-21 16:42 ` Christian Loehle
2025-11-24 16:30 ` Vincent Guittot
2025-11-24 16:40 ` Vincent Guittot
2025-11-25 12:03 ` Yu-Che Cheng
2025-11-21 17:58 ` Vincent Guittot
2025-11-21 18:25 ` Yu-Che Cheng
2025-11-25 9:46 ` Lukasz Luba
2025-11-25 13:01 ` Yu-Che Cheng
2025-11-26 9:35 ` Lukasz Luba
2025-11-20 10:55 ` Vincent Guittot
2025-11-21 3:00 ` Sergey Senozhatsky
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