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=-5.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,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 AACE5C4338F for ; Mon, 16 Aug 2021 12:32:49 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9193763266 for ; Mon, 16 Aug 2021 12:32:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233204AbhHPMdT (ORCPT ); Mon, 16 Aug 2021 08:33:19 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37222 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229600AbhHPMdQ (ORCPT ); Mon, 16 Aug 2021 08:33:16 -0400 Received: from casper.infradead.org (casper.infradead.org [IPv6:2001:8b0:10b:1236::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4012BC061764 for ; Mon, 16 Aug 2021 05:32:45 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=ACGN0Sis+sEgxBHlyEOjkA7hulSWZlh9kNBPQYj7W9Y=; b=maXa0e0PIztz0KhbIoRvGK18a1 9D1xwwKIi1DNOSd03ch/JGU1Zf0r8V/WKlyO++8Uc1cK1T0wIwChxoq0bq7foptzM110PBg9siWTV GCKGYZL6axig1YqggI/57YCFzKNWHq5iqwm8dEX3xQDUmtjwx7BGWLHWRaHPw0Vbv4kI7m1fGupoc gQjNgPNCpNPi/7UZqIqKTqGG7mtGDkzKhH1merBdLUgnkCORtvih8XROEdjxYghv8ZjNsUi/M0G3T GdifhbDbMs3MCD56FQGTmN7S8MocUpVxmMX4u6Q83rVyif9rrbt8iMV30sJwLF/JwFkSTHTOvi1MX Ms+twG2A==; Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=noisy.programming.kicks-ass.net) by casper.infradead.org with esmtpsa (Exim 4.94.2 #2 (Red Hat Linux)) id 1mFblo-001LKW-L1; Mon, 16 Aug 2021 12:31:20 +0000 Received: from hirez.programming.kicks-ass.net (hirez.programming.kicks-ass.net [192.168.1.225]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (Client did not present a certificate) by noisy.programming.kicks-ass.net (Postfix) with ESMTPS id 5C76E3004B2; Mon, 16 Aug 2021 14:31:09 +0200 (CEST) Received: by hirez.programming.kicks-ass.net (Postfix, from userid 1000) id 211E72028D932; Mon, 16 Aug 2021 14:31:09 +0200 (CEST) Date: Mon, 16 Aug 2021 14:31:09 +0200 From: Peter Zijlstra To: Josh Don Cc: Ingo Molnar , Juri Lelli , Vincent Guittot , Dietmar Eggemann , Steven Rostedt , Ben Segall , Mel Gorman , Daniel Bristot de Oliveira , Paul Turner , Oleg Rombakh , Viresh Kumar , Steve Sistare , Tejun Heo , Rik van Riel , linux-kernel@vger.kernel.org Subject: Re: [PATCH 2/2] sched: adjust SCHED_IDLE interactions Message-ID: References: <20210730020019.1487127-1-joshdon@google.com> <20210730020019.1487127-3-joshdon@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210730020019.1487127-3-joshdon@google.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Jul 29, 2021 at 07:00:19PM -0700, Josh Don wrote: > 1) Ignore min_granularity for determining the sched_slide of a > SCHED_IDLE entity when it is competing with a non SCHED_IDLE entity. > This reduces the latency of getting a non SCHED_IDLE entity back on cpu, > at the expense of increased context switch frequency of SCHED_IDLE > entities. > 2) Don't give sleeper credit to SCHED_IDLE entities when they wake onto > a cfs_rq with non SCHED_IDLE entities. As a result, newly woken > SCHED_IDLE entities will take longer to preempt non SCHED_IDLE entities. ISTR we had a rule about one change per patch :-)