Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755322AbcKJLDl (ORCPT ); Thu, 10 Nov 2016 06:03:41 -0500 Received: from ms01.sssup.it ([193.205.80.99]:22488 "EHLO sssup.it" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755305AbcKJLDk (ORCPT ); Thu, 10 Nov 2016 06:03:40 -0500 Subject: Re: [RFD] sched/deadline: Support single CPU affinity To: luca abeni , Peter Zijlstra References: <20161110080807.GD11311@worktop.programming.kicks-ass.net> <20161110100602.2781af72@sweethome> Cc: Ingo Molnar , Thomas Gleixner , Juri Lelli , Steven Rostedt , Claudio Scordino , Daniel Bistrot de Oliveira , Henrik Austad , linux-kernel@vger.kernel.org, "al.biondi@sssup.it" From: Tommaso Cucinotta Message-ID: <03a30c9c-eb42-c5c6-b94d-3a62048d8642@sssup.it> Date: Thu, 10 Nov 2016 12:03:47 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.4.0 MIME-Version: 1.0 In-Reply-To: <20161110100602.2781af72@sweethome> Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 952 Lines: 27 On 10/11/2016 10:06, luca abeni wrote: > is equivalent to the "least laxity first" (LLF) algorithm. > Giving precedence to tasks with 0 laxity is a technique that is often > used to improve the schedulability on multi-processor systems. EDZL (EDF / Zero Laxity first), right? AFAICR, there's quite a lot of analysis on EDZL for multi-cores... eg, Insik Shin et al.... http://ieeexplore.ieee.org/stamp/stamp.jsp?arnumber=6374195 But, before going the EDZL way, isn't it worthwhile to consider just splitting tasks among 2 cpus https://people.mpi-sws.org/~bbb/papers/pdf/rtss16b.pdf ? ... we're working at RETIS on simpler ways to make the AC for these split tasks cases (cc-ing Alessandro) that doesn't need demand-bound complex analysis... My2c, T. -- Tommaso Cucinotta, Computer Engineering PhD Associate Professor at the Real-Time Systems Laboratory (ReTiS) Scuola Superiore Sant'Anna, Pisa, Italy http://retis.sssup.it/people/tommaso