From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752219AbbE0VDS (ORCPT ); Wed, 27 May 2015 17:03:18 -0400 Received: from mx1.redhat.com ([209.132.183.28]:33895 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751595AbbE0VDR (ORCPT ); Wed, 27 May 2015 17:03:17 -0400 Message-ID: <55663113.40407@redhat.com> Date: Wed, 27 May 2015 17:03:15 -0400 From: Rik van Riel User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.3.0 MIME-Version: 1.0 To: Josef Bacik , mingo@redhat.com, peterz@infradead.org, linux-kernel@vger.kernel.org, kernel-team@fb.com Subject: Re: [PATCH] sched: prefer an idle cpu vs an idle sibling for BALANCE_WAKE References: <1432675865-378571-1-git-send-email-jbacik@fb.com> <55662460.2050501@fb.com> In-Reply-To: <55662460.2050501@fb.com> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 05/27/2015 04:09 PM, Josef Bacik wrote: > On 05/26/2015 05:31 PM, Josef Bacik wrote: >> SD_BALANCE_WAKE is supposed to find us an idle cpu to run on, however >> it is just >> looking for an idle sibling, preferring affinity over all else. This >> is not >> helpful in all cases, and SD_BALANCE_WAKE's job is to find us an idle >> cpu, not >> garuntee affinity. Fix this by first trying to find an idle sibling, >> and then >> if the cpu is not idle fall through to the logic to find an idle cpu. >> With this >> patch we get slightly better performance than with our forward port of >> SD_WAKE_IDLE. Thanks, >> > > I rigged up a test script to run the perf bench sched tests and give me > the numbers. Here are the numbers > > 4.0 > > Messaging: 56.934 Total runtime in seconds > Pipe: 105620.762 ops/sec > > 4.0 + my patch > > Messaging: 47.374 > Pipe: 113691.199 I did not get the email with your original patch, either to my inbox or my lkml folder, but I saw the patch on pastebin, and it looks good. When you resend it, please feel free to add my Acked-by: Rik van Riel Assuming the version you meant to email yesterday was the same one that you showed me on pastebin, of course :)