From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751974Ab3AOCdQ (ORCPT ); Mon, 14 Jan 2013 21:33:16 -0500 Received: from mga14.intel.com ([143.182.124.37]:28921 "EHLO mga14.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751023Ab3AOCdP (ORCPT ); Mon, 14 Jan 2013 21:33:15 -0500 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.84,469,1355126400"; d="scan'208";a="243827052" Message-ID: <50F4C027.1080806@intel.com> Date: Tue, 15 Jan 2013 10:34:15 +0800 From: Alex Shi User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:15.0) Gecko/20120912 Thunderbird/15.0.1 MIME-Version: 1.0 To: li guang CC: Preeti U Murthy , Morten Rasmussen , "mingo@redhat.com" , "peterz@infradead.org" , "tglx@linutronix.de" , "akpm@linux-foundation.org" , "arjan@linux.intel.com" , "bp@alien8.de" , "pjt@google.com" , "namhyung@kernel.org" , "efault@gmx.de" , "vincent.guittot@linaro.org" , "gregkh@linuxfoundation.org" , "linux-kernel@vger.kernel.org" Subject: Re: [PATCH v3 05/22] sched: remove domain iterations in fork/exec/wake References: <1357375071-11793-1-git-send-email-alex.shi@intel.com> <1357375071-11793-6-git-send-email-alex.shi@intel.com> <20130109182102.GC2046@e103034-lin> <50EF9B69.3000201@linux.vnet.ibm.com> <1357891316.2860.6.camel@liguang.fnst.cn.fujitsu.com> <50F02823.1070909@intel.com> <1358154191.8818.15.camel@liguang.fnst.cn.fujitsu.com> In-Reply-To: <1358154191.8818.15.camel@liguang.fnst.cn.fujitsu.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 01/14/2013 05:03 PM, li guang wrote: >>> > > This corner case may occur after "[PATCH v3 03/22] sched: fix >>> > > find_idlest_group mess logical" brought in the local sched_group bias, >>> > > and assume balancing runs on cpux2. >>> > > ideally, find_idlest_group should find the real idlest(this case: sgy), >>> > > then, this patch is reasonable. >>> > > >> > >> > Sure. but seems it is a bit hard to go down the idlest group. >> > >> > and the old logical is real cost too much, on my 2 socket NHM/SNB >> > server, hackbench can increase 2~5% performance. and no clean >> > performance on kbuild/aim7 etc. > what about remove local group bias? Any theory profit for non local group? Usually, bias toward local group will has cache locality profit. -- Thanks Alex