From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-3.5 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id D77AEC2D0A3 for ; Sun, 1 Nov 2020 16:24:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7400D2245F for ; Sun, 1 Nov 2020 16:24:35 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=gmx.net header.i=@gmx.net header.b="aRee6je3" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726902AbgKAQYe (ORCPT ); Sun, 1 Nov 2020 11:24:34 -0500 Received: from mout.gmx.net ([212.227.15.19]:48763 "EHLO mout.gmx.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726730AbgKAQYe (ORCPT ); Sun, 1 Nov 2020 11:24:34 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=gmx.net; s=badeba3b8450; t=1604247842; bh=pTUyR6tOXKepKJgE5JbfDuSLtn4tVdPcYcxIg81BW+4=; h=X-UI-Sender-Class:Subject:From:To:Cc:Date; b=aRee6je3IbkkLX/D2eiD7iOdW0Vdp79ciwQuWuXP0wMKwN3LPRIv6Wk7v39Vg0QpR 91hlYfFz9BuoTcoPHnaAnjWOQowprINuOiaGNaLlSdXcy54KqDorQwPUUZxFSxt2c+ cqjFKAnYm1z8XH6fd78LEB8/UT65QhUZ3ZJln1FY= X-UI-Sender-Class: 01bb95c1-4bf8-414a-932a-4f6e2808ef9c Received: from homer.simpson.net ([185.191.216.249]) by mail.gmx.com (mrgmx004 [212.227.17.190]) with ESMTPSA (Nemesis) id 1MSKuA-1kxMbK0DsW-00Scd0; Sun, 01 Nov 2020 17:24:02 +0100 Message-ID: <580d12716f6363d7404805fd4bc50e2d5ab459b0.camel@gmx.de> Subject: v5.8+ powersave governor breakage? From: Mike Galbraith To: lkml Cc: "Rafael J. Wysocki" , Peter Zijlstra Date: Sun, 01 Nov 2020 17:23:59 +0100 Content-Type: text/plain; charset="ISO-8859-15" User-Agent: Evolution 3.34.4 MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Provags-ID: V03:K1:Tou4lR2diKgAUlAyESwl6Zoea42IX/kWbC5uPoDT5iDSCxcdvec XS36GTEanaFfXEmzXToEl+2/2HmecYTkg2od39qgF9sBU3kNbDFB5Nyh0af9Rd3TBZ6oMx6 //uZuLO3dhk6kZVENnweSIKlgjJWDmwXgifAxdismTaZY2MQtHvwjk5KfjQB3yyBDyY/0CL ZwGI8u2q8Pw/hcwQdupKg== X-UI-Out-Filterresults: notjunk:1;V03:K0:f4tB0xzRtbY=:AXxcX1V7ogcSiZe5Tok9Zk 9Sq5heIuXxvM8XmFMklKSFBTNnRkIHr/xnKyA+7KVr1vNgPbMGvRo6jvZylPe6JWx37bwdXtf U92BiAHyA0S51tcZ6NwhbHja5I9CdqYrc/cGsuJ3Nfn63eFRvzAeRyl2PvSy0FsRFNC36WeEp tDsQ2FyjaSwcU5xKfQXBwvXZiZllw4X5OqrwcqZQEmhTVyHhMIt3kP762ryHSnRuQRxQvhjBI m1QzOfiQm3nJVqdAktR+4mfw3/Hj6Go7JmZLcJ+RcXdpXoHe5xCfoZM4rWvIR0GijIxMl6E6O xrus+VfPGeK8jg7dmpPwFSVjCpCc4gmZ7KdRIBQLbLSVDXVy380D6ld3UkSoAPiN0ttjdTS3V cZdsLUH9g2S6EyTv0QgfI50TNn8d8blTWLgfTTj9bTuE170umHk/NkLixX4kym94qUnZ40Ix8 bGEwP3ULittOZA5tHd/ghzRDcq7Zq+AiEUN4x5ob5yECPN/H4Bphvpk0NA3zVKg4Q8asLcnQu c4tPsfsOTqx9ojbUKnG5+hxLDGil9DAFWRaxZ9Nf6UjpcOoi1TxhZi8KKZnl2u7lvYQ5pqkY7 luAkiy0svVvUDIgQxYVJRer+mU1hIFipgmYKdpCJQ6xhzESjihtDbPSlUcVk5dje8sCaPZ6JV g2lA+GAfOKQK4e2C36qEt6FHf93mQhFNGjIsrctZ9lXvYzoYrTp2pyAO3vl001vb4ixk+ZYJL KlUKfijThfROloz3uJFBJkRJoI7HcrNEAaexCwpXqjWDnEcOrBt9oVIxzcSHYnI142tbguYR1 2DD3HOUrkcLDE23A2sSX6w96zyZjUr1F6wS2SblGOajSyfugYmZgk7Cpxyoe7KRDAWqwasYgP f7PQwi0x9QnXvRYUqWZA== Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Greetings, As you can see in the data below, my i4790 box used to default to the powersave governor despite CONFIG_CPU_FREQ_DEFAULT_GOV_ONDEMAND=y, and disallowed switching to ondemand. Post 5.8, powersave locks in at the lowest freq available, and while ondemand becomes the default, it takes a cross core scheduling performance hit compared to previous powersave. On a positive note, schedutil, which I used to have cause to avoid, seems to have improved a lot while I wasn't looking, and now actually improving cross core performance a wee bit. Seems I should configure stable 5.[89] kernels to use it as well. taskset 0xc pipe-test 1 CONFIG_CPU_FREQ_DEFAULT_GOV_ONDEMAND=y defaults to 5.4.74 2.183264 usecs/loop -- avg 2.179480 917.7 KHz powersave, ondemand not allowed 5.5.19 2.184331 usecs/loop -- avg 2.179776 917.5 KHz powersave, ondemand not allowed 5.6.19 2.198156 usecs/loop -- avg 2.204380 907.3 KHz powersave, ondemand not allowed 5.7.19 2.230582 usecs/loop -- avg 2.231981 896.1 KHz powersave, ondemand not allowed 5.8.17 3.203949 usecs/loop -- avg 3.207272 623.6 KHz ondemand 5.8.17 12.840411 usecs/loop -- avg 12.898500 155.1 KHz ondemand -> powersave 5.9.2 3.024442 usecs/loop -- avg 3.040023 657.9 KHz ondemand 5.9.2 12.348519 usecs/loop -- avg 12.299751 162.6 KHz ondemand -> powersave CONFIG_CPU_FREQ_DEFAULT_GOV_SCHEDUTIL=y due to db865272d9c4 5.10.gc2dc4c0 2.121057 usecs/loop -- avg 2.121487 942.7 KHz schedutil note: 4.0 GHz perfect! 5.10.gc2dc4c0 2.987989 usecs/loop -- avg 2.988658 669.2 KHz schedutil -> ondemand note: 2.9 GHz not so perfect 5.10.gc2dc4c0 12.447348 usecs/loop -- avg 12.475363 160.3 KHz schedutil -> powersave note: 800 MHz heeelp meee 5.10.gc2dc4c0 2.135548 usecs/loop -- avg 2.137868 935.5 KHz schedutil -> performance note: 4.0 GHz (obviously)