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 23E5ECD6E5D for ; Wed, 11 Oct 2023 11:50:30 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1346103AbjJKLu3 (ORCPT ); Wed, 11 Oct 2023 07:50:29 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50360 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231935AbjJKLu1 (ORCPT ); Wed, 11 Oct 2023 07:50:27 -0400 Received: from mail-pl1-x62b.google.com (mail-pl1-x62b.google.com [IPv6:2607:f8b0:4864:20::62b]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A84348F for ; Wed, 11 Oct 2023 04:50:04 -0700 (PDT) Received: by mail-pl1-x62b.google.com with SMTP id d9443c01a7336-1c62d61dc96so43281375ad.0 for ; Wed, 11 Oct 2023 04:50:04 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bytedance.com; s=google; t=1697025004; x=1697629804; darn=vger.kernel.org; h=content-transfer-encoding:in-reply-to:from:references:cc:to :content-language:subject:user-agent:mime-version:date:message-id :from:to:cc:subject:date:message-id:reply-to; bh=6jXMPoHtqd/Hx6fmqzikg66SSiek1hyl8J8uZ94eBkM=; b=MlMVuK9l7ZchBCdcVeYq02hScRLv77WoJSIsU6f5kw0TpCul/0wKQGN6VTV82eZUXU QHHaq6ExGub6eUD0OXZK1ZI9Ced5do382vChI0CwvL0u9ajCKyqm17weKASdAQhmwE1u ksH9S9nxFiUp54yfpm/y49LrdpSz/HGdXq5RN0AImu/NLB3RbVlfixgeK3IO0cAjr7lC 0EShU8CGjR2HWTXlLQ4+FzsMZpEZ3uAFde59ImSR4Gc8bruMySsDjNw1a323GVkmzKDP v2v+EwUw++hSr6KHqHUPh9K1V/gOpqQ/nMJSYF5lLugU57tFi+Krs+sdAUggQ9UjU/QR GJpg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1697025004; x=1697629804; h=content-transfer-encoding:in-reply-to:from:references:cc:to :content-language:subject:user-agent:mime-version:date:message-id :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=6jXMPoHtqd/Hx6fmqzikg66SSiek1hyl8J8uZ94eBkM=; b=lTjVkh6XmYG6TGvIvZGDoW8CkziPPkNSODUDN/OlGgIZDVjOssCWBV1Vtzzg1JDB6g Bo5OGEhDDfjjd/xpHRTssUTGcUOjTJ6LEEsvPISW1Qbfnvpsbhxj0iuZCSbi2RirMTrn 6wVGJl4yepvvVXLT6slHbP+jeoO1vepbmGNZB/akRoBwav04aueKq3zVXTuQddohPZPf 9Ckkl7ctBBJ59drbfAloDn6zrqSIRRobk02HAcW9GAECe6hzD9lMblQuC6PtGuvQNuQJ Dw5b1pXc7H+JWKxJIZVipCnqEl8BYHhEP/0s4+gxPwJ+zVN6kXnSIcLfaUAcSzZyyYvr aRwA== X-Gm-Message-State: AOJu0YwyfcgilhpI1zAwEgKRvYu1cPu0iouN/hlCigtd9cisVWb0/T/s +7xWBVMWNx8bmYb2enj2U/t+cQ== X-Google-Smtp-Source: AGHT+IEDCqXJj3YOhgBFw9VpCN1j9W+/kcrhhPe3h0VKXOEk8qhAXQDlXRw7da3dwnXFhyKLZaiHdQ== X-Received: by 2002:a17:903:32cf:b0:1c9:c3eb:6557 with SMTP id i15-20020a17090332cf00b001c9c3eb6557mr3824638plr.0.1697025004127; Wed, 11 Oct 2023 04:50:04 -0700 (PDT) Received: from [10.84.153.115] ([203.208.167.147]) by smtp.gmail.com with ESMTPSA id d3-20020a170902c18300b001a5fccab02dsm13752060pld.177.2023.10.11.04.49.54 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 11 Oct 2023 04:50:02 -0700 (PDT) Message-ID: Date: Wed, 11 Oct 2023 19:49:52 +0800 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: Re: [PATCH 05/15] sched/fair: Implement an EEVDF like policy Content-Language: en-US To: Peter Zijlstra Cc: Benjamin Segall , mingo@kernel.org, vincent.guittot@linaro.org, linux-kernel@vger.kernel.org, juri.lelli@redhat.com, dietmar.eggemann@arm.com, rostedt@goodmis.org, mgorman@suse.de, bristot@redhat.com, corbet@lwn.net, qyousef@layalina.io, chris.hyser@oracle.com, patrick.bellasi@matbug.net, pjt@google.com, pavel@ucw.cz, qperret@google.com, tim.c.chen@linux.intel.com, joshdon@google.com, timj@gnu.org, kprateek.nayak@amd.com, yu.c.chen@intel.com, youssefesmat@chromium.org, joel@joelfernandes.org, efault@gmx.de, tglx@linutronix.de References: <20230531115839.089944915@infradead.org> <20230531124603.931005524@infradead.org> <20231011073317.GJ14330@noisy.programming.kicks-ass.net> From: Abel Wu In-Reply-To: <20231011073317.GJ14330@noisy.programming.kicks-ass.net> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 10/11/23 3:33 PM, Peter Zijlstra Wrote: > On Wed, Oct 11, 2023 at 12:14:30PM +0800, Abel Wu wrote: > >> there are cases worthy of breaking the 'eligible' rule. > > See the discussion with Youssef, if we weaken the eligible rule you get > horrific interference because you end up placing new tasks around the > 0-lag point. I have just begun studying the EEVDF scheduler, and obviously there are lots of things to catch up with :) At a quick glance at Youssef's first reply, I'm sure that's exactly the same as I thought about, the EVDF. The intention behind is w/o eligibility the task_timeline can be organized by deadline rather than vruntime, hence task selection can be done in O(1) while the min_vruntime can be updated through augmented rbtree. Anyway, I will learn from your discussion with Youssef first, thanks for providing the info! Best, Abel