Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934456Ab2J0Dgj (ORCPT ); Fri, 26 Oct 2012 23:36:39 -0400 Received: from e28smtp03.in.ibm.com ([122.248.162.3]:51542 "EHLO e28smtp03.in.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934411Ab2J0Dgi (ORCPT ); Fri, 26 Oct 2012 23:36:38 -0400 Message-ID: <508B56A7.1010501@linux.vnet.ibm.com> Date: Sat, 27 Oct 2012 09:06:07 +0530 From: Preeti U Murthy User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:14.0) Gecko/20120717 Thunderbird/14.0 MIME-Version: 1.0 To: Ingo Molnar CC: Peter Zijlstra , svaidy@linux.vnet.ibm.com, linux-kernel@vger.kernel.org, venki@google.com, robin.randhawa@arm.com, linaro-dev@lists.linaro.org, mjg59@srcf.ucam.org, viresh.kumar@linaro.org, akpm@linux-foundation.org, amit.kucheria@linaro.org, deepthi@linux.vnet.ibm.com, paul.mckenney@linaro.org, arjan@linux.intel.com, paulmck@linux.vnet.ibm.com, srivatsa.bhat@linux.vnet.ibm.com, vincent.guittot@linaro.org, tglx@linutronix.de, Arvind.Chauhan@arm.com, pjt@google.com, Morten.Rasmussen@arm.com, linux-arm-kernel@lists.infradead.org, suresh.b.siddha@intel.com Subject: Re: [RFC PATCH 00/13] sched: Integrating Per-entity-load-tracking with the core scheduler References: <20121025102045.21022.92489.stgit@preeti.in.ibm.com> <1351180603.12171.31.camel@twins> <50898118.1050402@linux.vnet.ibm.com> <1351254553.16863.52.camel@twins> <20121026130715.GB9886@gmail.com> In-Reply-To: <20121026130715.GB9886@gmail.com> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit x-cbid: 12102703-3864-0000-0000-000005416173 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1828 Lines: 53 On 10/26/2012 06:37 PM, Ingo Molnar wrote: > > * Peter Zijlstra wrote: > >> [...] >> >> So a sane series would introduce maybe two functions: >> cpu_load() and task_load() and use those where we now use >> rq->load.weight and p->se.load.weight for load balancing >> purposes. Implement these functions using those two >> expression. So effectively this patch is a NOP. >> >> Secondly, switch these two functions over to the per-task >> based averages. >> >> Tada! all done. The load balancer will then try and equalize >> effective load instead of instant load. >> >> It will do the 3x10% vs 100% thing correctly with just those >> two patches. Simply because it will report a lower cpu-load >> for the 3x10% case than it will for the 100% case, no need to >> go fudge about in the load-balance internals. >> >> Once you've got this correctly done, you can go change >> balancing to better utilize the new metric, like use the >> effective load instead of nr_running against the capacity and >> things like that. But for every such change you want to be >> very careful and run all the benchmarks you can find -- in >> fact you want to do that after the 2nd patch too. > > If anyone posted that simple two-patch series that switches over > to the new load metrics I'd be happy to test the performance of > those. > > Having two parallel load metrics is really not something that we > should tolerate for too long. > > Thanks, > > Ingo > Right Ingo.I will incorporate this approach and post out very soon. Thank you Regards Preeti -- 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/