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Wysocki" , Linux PM , Aboorva Devarajan Cc: LKML , Daniel Lezcano Date: Thu, 23 Jan 2025 18:54:33 +0200 In-Reply-To: <842b1500-9f4f-47e5-9777-ee89351f956e@arm.com> References: <4953183.GXAFRqVoOG@rjwysocki.net> <13679187.uLZWGnKmhe@rjwysocki.net> <842b1500-9f4f-47e5-9777-ee89351f956e@arm.com> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable User-Agent: Evolution 3.52.4 (3.52.4-2.fc40) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 On Fri, 2025-01-10 at 13:16 +0000, Christian Loehle wrote: > This would then enable intercept-detection only for <50% of the time, > another option is to not allow intercepts selecting a polling state, but > there were recent complaints about this exact behavior from Aboorva (+TO)= . > They don't have a low-latency non-polling state. What folks think about the following idea. Idle governor algorithm essentially predicts the sleep time (step 1), based= on that, the idle state gets selected (step 2). What if we add a sleep time factor and expose it via sysfs. The predicted s= leep time would be multiplied by the factor (between steps 1 and 2). Default factor value is 1 (or 100%). If users want teo be more hesitant selecting deeper idle states, they can set it to 0.5 (or 50%) or some other value < 1. I users want teo to be more enthusiastic about selecting deeper = idle states, they set the factor to a value > 1. We could expose it via sysfs and allow changing in some reasonable range. The idea is to let users adjust the level of idle governor (teo in this cas= e) enthusiasm regarding deep C-state. Thanks, Artem.