Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754297AbaFCNWg (ORCPT ); Tue, 3 Jun 2014 09:22:36 -0400 Received: from fw-tnat.austin.arm.com ([217.140.110.23]:43525 "EHLO collaborate-mta1.arm.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1753881AbaFCNWX (ORCPT ); Tue, 3 Jun 2014 09:22:23 -0400 Date: Tue, 3 Jun 2014 14:22:18 +0100 From: Morten Rasmussen To: Vincent Guittot Cc: "peterz@infradead.org" , "mingo@kernel.org" , "linux-kernel@vger.kernel.org" , "linux@arm.linux.org.uk" , "linux-arm-kernel@lists.infradead.org" , "preeti@linux.vnet.ibm.com" , "efault@gmx.de" , "nicolas.pitre@linaro.org" , "linaro-kernel@lists.linaro.org" , "daniel.lezcano@linaro.org" Subject: Re: [PATCH v2 04/11] sched: Allow all archs to set the power_orig Message-ID: <20140603132217.GD29593@e103034-lin> References: <1400860385-14555-1-git-send-email-vincent.guittot@linaro.org> <1400860385-14555-5-git-send-email-vincent.guittot@linaro.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1400860385-14555-5-git-send-email-vincent.guittot@linaro.org> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, May 23, 2014 at 04:52:58PM +0100, Vincent Guittot wrote: > power_orig is only changed for system with a SMT sched_domain level in order to > reflect the lower capacity of CPUs. Heterogenous system also have to reflect an > original capacity that is different from the default value. > > Create a more generic function arch_scale_cpu_power that can be also used by > non SMT platform to set power_orig. I did a quick test of the patch set with adjusting cpu_power on big.LITTLE (ARM TC2) to reflect the different compute capacities of the A15s and A7s. I ran the sysbench cpu benchmark with 5 threads with and without the patches applied, but with non-default cpu_powers. I didn't see any difference in the load-balance. Three tasks ended up on the two A15s and two tasks ended up on two of the three A7s leaving one unused in both cases. Using default cpu_power I get one task on each of the five cpus (best throughput). Unless I messed something up, it seems that setting cpu_power doesn't give me the best throughput with these patches applied. Have you done any tests on big.LITTLE? Morten -- 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/