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Tue, 03 Feb 2026 13:02:15 -0800 (PST) Date: Tue, 3 Feb 2026 16:02:15 -0500 From: Johannes Weiner To: Peter Zijlstra Cc: Suren Baghdasaryan , Ingo Molnar , Chengming Zhou , Dietmar Eggemann , John Stultz , linux-kernel@vger.kernel.org Subject: Re: [PATCH resend 1/2] sched: psi: loosen clock sync between scheduler and aggregator Message-ID: References: <20260114154317.1815429-1-hannes@cmpxchg.org> <20260128103514.GX171111@noisy.programming.kicks-ass.net> <20260128201743.GW166857@noisy.programming.kicks-ass.net> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: 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.