From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id EED05231842; Fri, 17 Oct 2025 18:37:25 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.140.110.172 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1760726248; cv=none; b=U7YFKNDOmPmW8n9KwKB9ltRyEJg3c5nA/tZA0Aoy2w5KEDZQ2R31vznC4WXz4YX3kTH225Gq7TzUQ0dPnsCoB959IxX5mXOIITy/p2qC+yrrhOFcybaEbspS8LDtHDrboonL49bIumB3rbZWXznKJ6Oj8ljGCmXvcPokN6SjZRg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1760726248; c=relaxed/simple; bh=V9nRtprV4Fy3L/RtjgTOBjGRXGt7eZgwB6iGwK71cSY=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=SwVxEd4mpJCGuP4vxjUWy7tRr2rP/Jrq7qq1OVR22b/hq8EQkGw1rf2/qsWPtZqWMY0d64LwQtAnhQejjWSU78BvRV+dYCTabkJxPAJWXHhJGUbJaGCXMd9hSdlKIorUmuANmOnhT9Z+3T22EGf124r4Oz4OK7zoaKBEU35AXjM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com; spf=pass smtp.mailfrom=arm.com; arc=none smtp.client-ip=217.140.110.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=arm.com Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 750591595; Fri, 17 Oct 2025 11:37:17 -0700 (PDT) Received: from [10.1.35.23] (e127648.arm.com [10.1.35.23]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id BAF653F6A8; Fri, 17 Oct 2025 11:37:23 -0700 (PDT) Message-ID: <28ecb23b-ecee-409a-9771-24f801081d07@arm.com> Date: Fri, 17 Oct 2025 19:37:21 +0100 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v1] cpuidle: governors: menu: Predict longer idle time when in doubt To: "Rafael J. Wysocki" Cc: Linux PM , Sergey Senozhatsky , LKML , Artem Bityutskiy , Tomasz Figa , Doug Smythies References: <4687373.LvFx2qVVIh@rafael.j.wysocki> <5f0aa630-b30a-44c4-a52c-e08179cd3bf9@arm.com> Content-Language: en-US From: Christian Loehle In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit On 10/17/25 10:39, Rafael J. Wysocki wrote: > On Fri, Oct 17, 2025 at 10:22 AM Christian Loehle > wrote: >> >> On 10/16/25 17:25, Rafael J. Wysocki wrote: >>> From: Rafael J. Wysocki >>> >>> It is reported that commit 85975daeaa4d ("cpuidle: menu: Avoid discarding >>> useful information") led to a performance regression on Intel Jasper Lake >>> systems because it reduced the time spent by CPUs in idle state C7 which >>> is correlated to the maximum frequency the CPUs can get to because of an >>> average running power limit [1]. >>> [snip] >> [snip] >> Anyway, the patch makes sense, let me run some tests and get back. > > Thanks! Unfortunately this patch regresses my tests about as much as a revert of 85975daeaa4d would. (menu-1 is $SUBJECT, menu-m current mainline, menu-r mainline with 85975daeaa4d reverted): device gov iter iops idles idle_misses idle_miss_ratio belows aboves mmcblk1 menu-1 0 1523 402522 119988 0.298 98552 21436 mmcblk1 menu-1 1 1481 395766 118596 0.300 97640 20956 mmcblk1 menu-1 2 1503 396560 117876 0.297 97506 20370 mmcblk1 menu-m 0 2355 703732 22275 0.032 2628 19647 mmcblk1 menu-m 1 2359 637522 24815 0.039 4075 20740 mmcblk1 menu-m 2 2356 706980 23836 0.034 3208 20628 mmcblk1 menu-r 0 1490 388180 118294 0.305 97871 20423 mmcblk1 menu-r 1 1498 393402 119984 0.305 99187 20797 mmcblk1 menu-r 2 1462 388597 119504 0.308 98640 20864 mmcblk2 menu-1 0 3303 503938 170251 0.338 150276 19975 mmcblk2 menu-1 1 3310 480508 132132 0.275 114398 17734 mmcblk2 menu-1 2 3554 466884 113659 0.243 95841 17818 mmcblk2 menu-m 0 5746 706262 24618 0.035 3802 20816 mmcblk2 menu-m 1 5741 727174 24152 0.033 3737 20415 mmcblk2 menu-m 2 5777 836940 12424 0.015 335 12089 mmcblk2 menu-r 0 3241 463112 133052 0.287 114616 18436 mmcblk2 menu-r 1 3551 422006 100494 0.238 82425 18069 mmcblk2 menu-r 2 3523 508542 140085 0.275 122880 17205 nvme0n1 menu-1 0 5407 436834 74314 0.170 54133 20181 nvme0n1 menu-1 1 5763 459510 72673 0.158 51530 21143 nvme0n1 menu-1 2 6266 489570 78651 0.161 58609 20042 nvme0n1 menu-m 0 10786 767740 23840 0.031 2855 20985 nvme0n1 menu-m 1 10586 757540 23612 0.031 2933 20679 nvme0n1 menu-m 2 11805 834012 23528 0.028 2768 20760 nvme0n1 menu-r 0 5323 431906 77426 0.179 56166 21260 nvme0n1 menu-r 1 5484 438142 76033 0.174 55956 20077 nvme0n1 menu-r 2 5353 428826 77024 0.180 57016 20008 sda menu-1 0 972 444116 149643 0.337 129023 20620 sda menu-1 1 954 557068 176479 0.317 159092 17387 sda menu-1 2 878 540360 196405 0.363 176792 19613 sda menu-m 0 1634 1017918 29614 0.029 8587 21027 sda menu-m 1 1622 878140 25323 0.029 8238 17085 sda menu-m 2 1632 1027167 28798 0.028 8428 20370 sda menu-r 0 918 531112 188314 0.355 168375 19939 sda menu-r 1 924 521378 185727 0.356 165327 20400 sda menu-r 2 880 529146 196391 0.371 176908 19483 nullb0 menu-1 0 101419 88988 23923 0.269 3080 20843 nullb0 menu-1 1 101610 88484 23678 0.268 2821 20857 nullb0 menu-1 2 101369 89336 23711 0.265 2795 20916 nullb0 menu-m 0 101696 88698 23860 0.269 2910 20950 nullb0 menu-m 1 101103 88120 23294 0.264 3295 19999 nullb0 menu-m 2 101880 86676 22730 0.262 2709 20021 nullb0 menu-r 0 101856 87742 23493 0.268 3204 20289 nullb0 menu-r 1 101514 89070 23653 0.266 2848 20805 nullb0 menu-r 2 101754 86318 23163 0.268 3229 19934 mtdblock3 menu-1 0 163 350284 115149 0.329 97166 17983 mtdblock3 menu-1 1 179 315948 99038 0.313 78243 20795 mtdblock3 menu-1 2 134 481584 160754 0.334 144150 16604 mtdblock3 menu-m 0 215 410034 70261 0.171 55445 14816 mtdblock3 menu-m 1 205 570150 109273 0.192 90189 19084 mtdblock3 menu-m 2 252 866616 23492 0.027 9717 13775 mtdblock3 menu-r 0 132 467365 161835 0.346 144056 17779 mtdblock3 menu-r 1 164 348682 117704 0.338 97859 19845 mtdblock3 menu-r 2 132 483300 165179 0.342 147164 18015