From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S265083AbTLWKRZ (ORCPT ); Tue, 23 Dec 2003 05:17:25 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S265094AbTLWKRZ (ORCPT ); Tue, 23 Dec 2003 05:17:25 -0500 Received: from mail-10.iinet.net.au ([203.59.3.42]:9607 "HELO mail.iinet.net.au") by vger.kernel.org with SMTP id S265083AbTLWKRY (ORCPT ); Tue, 23 Dec 2003 05:17:24 -0500 Message-ID: <3FE81563.7040505@cyberone.com.au> Date: Tue, 23 Dec 2003 21:13:55 +1100 From: Nick Piggin User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.4) Gecko/20030827 Debian/1.4-3 X-Accept-Language: en MIME-Version: 1.0 To: "Nakajima, Jun" CC: Con Kolivas , linux kernel mailing list Subject: Re: [PATCH] 2.6.0 batch scheduling, HT aware References: <7F740D512C7C1046AB53446D372001736187E6@scsmsx402.sc.intel.com> In-Reply-To: <7F740D512C7C1046AB53446D372001736187E6@scsmsx402.sc.intel.com> Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Nakajima, Jun wrote: >BTW, Nick, does your SMT scheduler have "idle package prioritization" >which chooses an idle logical processor with the other local processor >idle if any (rather than just an idle processor with other local >processor running at full speed), when the scheduler requires an idle >local processor? That would prevent situations like two logical >processors run at full speed in the same processor package, with the >other processor package(s) idle in a same processor package(s). I >haven't reviewed your latest patch closely, and that is the one of the >things I want to do during the holidays. > Yep, sched_balance_wake wakes to idle siblings if your domain has SD_FLAG_WAKE and idle_balance tries pulling tasks from any domain with SD_FLAG_NEWIDLE set if we're just about to become idle. > >One question. Why did you remove SD_FLAG_IDLE flag from cpu_domain >initialization in the w27 patch? We've been seeing some performance >degradation with w27, compared to w26. > I reworked things to not require this hopefully. w26 was quite broken with respect to the active balancing stuff. One thing I did in w27 was accidently release the code with cache_hot_time for the SMT domain set to 1ms instead of 0 in w26, so SD_FLAG_NEWIDLE is sometimes not allowed to pull a ready-to-run task off a sibling... I haven't been able to do a great deal of performance tuning though, there is probably quite a bit of room for improvement.