From: Johannes Weiner <hannes@cmpxchg.org>
To: Peter Zijlstra <peterz@infradead.org>
Cc: Suren Baghdasaryan <surenb@google.com>,
Ingo Molnar <mingo@kernel.org>,
Chengming Zhou <chengming.zhou@linux.dev>,
Dietmar Eggemann <dietmar.eggemann@arm.com>,
John Stultz <jstultz@google.com>,
linux-kernel@vger.kernel.org
Subject: Re: [PATCH resend 1/2] sched: psi: loosen clock sync between scheduler and aggregator
Date: Tue, 3 Feb 2026 16:02:15 -0500 [thread overview]
Message-ID: <aYJiVzHpLcIXusrh@cmpxchg.org> (raw)
In-Reply-To: <aYIWXJ_Ms030Ppaj@cmpxchg.org>
On Tue, Feb 03, 2026 at 10:38:09AM -0500, Johannes Weiner wrote:
> Yes. The backward motion is what caused the multi-second errors that
> immediately shift even the long-term averages. Those are blatantly
> noticable and cause practical issues. And notably, these were the ONLY
> issue anyone reported against 3840cbe24cf0 in three years.
Grr.
"[...] reported against df77430639c9 ("psi: Reduce calls to
ched_clock() in psi") in three years", of course.
prev parent reply other threads:[~2026-02-03 21:02 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-01-14 15:43 [PATCH resend 1/2] sched: psi: loosen clock sync between scheduler and aggregator Johannes Weiner
2026-01-14 15:43 ` [PATCH resend 2/2] sched: psi: use rq_clock() during task state changes Johannes Weiner
2026-02-02 20:41 ` Peter Zijlstra
2026-02-03 16:34 ` Johannes Weiner
2026-01-28 10:35 ` [PATCH resend 1/2] sched: psi: loosen clock sync between scheduler and aggregator Peter Zijlstra
2026-01-28 18:56 ` Johannes Weiner
2026-01-28 20:17 ` Peter Zijlstra
2026-02-03 15:38 ` Johannes Weiner
2026-02-03 21:02 ` Johannes Weiner [this message]
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