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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id B1C8AC433F5 for ; Sun, 9 Oct 2022 06:16:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229917AbiJIGQL convert rfc822-to-8bit (ORCPT ); Sun, 9 Oct 2022 02:16:11 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46390 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229912AbiJIGQJ (ORCPT ); Sun, 9 Oct 2022 02:16:09 -0400 X-Greylist: delayed 606 seconds by postgrey-1.37 at lindbergh.monkeyblade.net; Sat, 08 Oct 2022 23:16:06 PDT Received: from relay.hostedemail.com (smtprelay0015.hostedemail.com [216.40.44.15]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4D4D332B9A for ; Sat, 8 Oct 2022 23:16:06 -0700 (PDT) Received: from omf07.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay07.hostedemail.com (Postfix) with ESMTP id 56F2B1613CB; Sun, 9 Oct 2022 06:05:57 +0000 (UTC) Received: from [HIDDEN] (Authenticated sender: rostedt@goodmis.org) by omf07.hostedemail.com (Postfix) with ESMTPA id 373F220024; Sun, 9 Oct 2022 06:05:42 +0000 (UTC) Date: Sat, 08 Oct 2022 17:59:13 -0400 From: Steven Rostedt To: David Laight , 'Youssef Esmat' , Vincent Guittot CC: "mingo@redhat.com" , "peterz@infradead.org" , "juri.lelli@redhat.com" , "dietmar.eggemann@arm.com" , "bsegall@google.com" , "mgorman@suse.de" , "bristot@redhat.com" , "vschneid@redhat.com" , "linux-kernel@vger.kernel.org" , "parth@linux.ibm.com" , "qais.yousef@arm.com" , "chris.hyser@oracle.com" , "valentin.schneider@arm.com" , "patrick.bellasi@matbug.net" , "pjt@google.com" , "pavel@ucw.cz" , "tj@kernel.org" , "qperret@google.com" , "tim.c.chen@linux.intel.com" , "joshdon@google.com" , "timj@gnu.org" , "joel@joelfernandes.org" Subject: RE: [PATCH v5 7/7] sched/fair: Add latency list User-Agent: K-9 Mail for Android In-Reply-To: <39d4ea27cfce4b7d977605f37f6da6fb@AcuMS.aculab.com> References: <20220925143908.10846-1-vincent.guittot@linaro.org> <20220925143908.10846-8-vincent.guittot@linaro.org> <39d4ea27cfce4b7d977605f37f6da6fb@AcuMS.aculab.com> Message-ID: <257E96C2-6ABD-4DD6-9B7F-771DA3D1BAAA@goodmis.org> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8BIT X-Stat-Signature: cyc6noeo5g3c4eqkrhbkxiwc3f66kg9c X-Rspamd-Server: rspamout08 X-Rspamd-Queue-Id: 373F220024 X-Session-Marker: 726F737465647440676F6F646D69732E6F7267 X-Session-ID: U2FsdGVkX1/XhhVD35EfmLizu6qrdXCxDgPd/Tr9QVo= X-HE-Tag: 1665295542-118199 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On October 8, 2022 5:14:54 PM EDT, David Laight wrote: >... >> Have we considered an approach where the task that is marked as >> latency sensitive gets a boosted nice value when it sleeps and is >> either scaled down exponentially as it runs, or immediately reset to >> its default when it runs for one tick? > >Or use the RT scheduler for anything that requires low latency. >Isn't that what it is for? > The RT scheduler is for tasks that require strick scheduling requirements over all else, including performance. But we are seeing latency issues for tasks that don't have such requirements but this latency effects its quality. -- Steve -- Sent from my Android device with K-9 Mail. Please excuse my brevity and top posting.