Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755541Ab2BWLLu (ORCPT ); Thu, 23 Feb 2012 06:11:50 -0500 Received: from e28smtp01.in.ibm.com ([122.248.162.1]:60711 "EHLO e28smtp01.in.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754798Ab2BWLLs (ORCPT ); Thu, 23 Feb 2012 06:11:48 -0500 Date: Thu, 23 Feb 2012 16:19:59 +0530 From: Srivatsa Vaddagiri To: Mike Galbraith Cc: Peter Zijlstra , Suresh Siddha , linux-kernel , Ingo Molnar , Paul Turner Subject: Re: sched: Avoid SMT siblings in select_idle_sibling() if possible Message-ID: <20120223104959.GA8454@linux.vnet.ibm.com> Reply-To: Srivatsa Vaddagiri References: <1321435455.5072.64.camel@marge.simson.net> <1321468646.11680.2.camel@sbsiddha-desk.sc.intel.com> <1321495153.5100.7.camel@marge.simson.net> <1321544313.6308.25.camel@marge.simson.net> <1321545376.2495.1.camel@laptop> <1321547917.6308.48.camel@marge.simson.net> <1321551381.15339.21.camel@sbsiddha-desk.sc.intel.com> <1321629267.7080.13.camel@marge.simson.net> <1329748861.2293.345.camel@twins> <1329761661.6276.146.camel@marge.simpson.net> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline In-Reply-To: <1329761661.6276.146.camel@marge.simpson.net> User-Agent: Mutt/1.5.21 (2010-09-15) x-cbid: 12022310-4790-0000-0000-000001747ADA Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1259 Lines: 37 * Mike Galbraith [2012-02-20 19:14:21]: > > I was looking at this code due to vatsa wanting to do SD_BALANCE_WAKE. > > I really really need to find time to do systematic mainline testing. > > Enabling SD_BALANCE_WAKE used to be decidedly too expensive to consider. > Maybe that has changed, but I doubt it. (general aside: testing with a > bloated distro config is a big mistake) I am seeing 2.6% _improvement_ in volanomark score by enabling SD_BALANCE_WAKE at SMT/MC domains. Machine : 2 Quad-core Intel X5570 CPU (H/T enabled) Kernel : tip (HEAD at 6241cc8) Java : OpenJDK 1.6.0_20 Volano : 2_9_0 Volano benchmark was run 4 times with and w/o SD_BALANCE_WAKE enabled in SMT/MC domains. Average score std. dev SD_BALANCE_WAKE disabled 369459.750 4825.046 SD_BALANCE_WAKE enabled 379070.500 379070.5 I am going to try pipe benchmark next. Do you have suggestions for any other benchmarks I should try to see the effect of SD_BALANCE_WAKE turned on in SMT/MC domains? - vatsa -- 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/