From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755124Ab3EBHg5 (ORCPT ); Thu, 2 May 2013 03:36:57 -0400 Received: from e23smtp01.au.ibm.com ([202.81.31.143]:50728 "EHLO e23smtp01.au.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751545Ab3EBHgz (ORCPT ); Thu, 2 May 2013 03:36:55 -0400 Message-ID: <5182178A.5020607@linux.vnet.ibm.com> Date: Thu, 02 May 2013 15:36:42 +0800 From: Michael Wang User-Agent: Mozilla/5.0 (X11; Linux i686; rv:16.0) Gecko/20121011 Thunderbird/16.0.1 MIME-Version: 1.0 To: Mike Galbraith CC: Peter Zijlstra , LKML , Ingo Molnar , Alex Shi , Namhyung Kim , Paul Turner , Andrew Morton , "Nikunj A. Dadhania" , Ram Pai Subject: Re: [PATCH] sched: wake-affine throttle References: <5164DCE7.8080906@linux.vnet.ibm.com> <1366626208.2721.12.camel@laptop> <5181FE1B.6010508@linux.vnet.ibm.com> <1367478643.5808.71.camel@marge.simpson.net> In-Reply-To: <1367478643.5808.71.camel@marge.simpson.net> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Content-Scanned: Fidelis XPS MAILER x-cbid: 13050207-1618-0000-0000-000003CE42BF Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 05/02/2013 03:10 PM, Mike Galbraith wrote: >> >> I've done the test for several times, also compared with the throttle >> approach, default 1ms interval still works very well, the regression on >> hackbench start to exceed 2% when interval become 100ms on my box, but >> please note the pgbench already gain a lot benefit at that time. >> >> I think now we could say that wake-affine is useful, and we could not >> simply kill it. > > Oh, it's definitely useful. Communicating tasks deeply resent talking > over interconnects (advanced tin cans and string). My little Q6600 box > can even be described as dinky-numa given enough imagination.. place > communicating tasks on different core2 "nodes" if you will, throughput > falls through the floor. Shared L2 is quick like bunny, dram ain't. Nice, so we got another proof to defend wake-affine now ;-) Regards, Michael Wang > > -Mike > > -- > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > Please read the FAQ at http://www.tux.org/lkml/ >