From mboxrd@z Thu Jan 1 00:00:00 1970 From: Alex Shi Subject: Re: [patch v7 0/21] sched: power aware scheduling Date: Sun, 14 Apr 2013 09:28:50 +0800 Message-ID: <516A0652.8040505@intel.com> References: <1365040862-8390-1-git-send-email-alex.shi@intel.com> <516724F5.20504@kernel.org> <5167C9FA.8050406@intel.com> <20130412162348.GE2368@pd.tnic> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Return-path: Received: from mga01.intel.com ([192.55.52.88]:19032 "EHLO mga01.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754055Ab3DNB3E (ORCPT ); Sat, 13 Apr 2013 21:29:04 -0400 In-Reply-To: <20130412162348.GE2368@pd.tnic> Sender: linux-pm-owner@vger.kernel.org List-Id: linux-pm@vger.kernel.org To: Borislav Petkov Cc: Len Brown , mingo@redhat.com, peterz@infradead.org, tglx@linutronix.de, akpm@linux-foundation.org, arjan@linux.intel.com, pjt@google.com, namhyung@kernel.org, efault@gmx.de, morten.rasmussen@arm.com, vincent.guittot@linaro.org, gregkh@linuxfoundation.org, preeti@linux.vnet.ibm.com, viresh.kumar@linaro.org, linux-kernel@vger.kernel.org, len.brown@intel.com, rafael.j.wysocki@intel.com, jkosina@suse.cz, clark.williams@gmail.com, tony.luck@intel.com, keescook@chromium.org, mgorman@suse.de, riel@redhat.com, Linux PM list On 04/13/2013 12:23 AM, Borislav Petkov wrote: > On Fri, Apr 12, 2013 at 04:46:50PM +0800, Alex Shi wrote: >> > Thanks a lot for comments, Len! > AFAICT, you kinda forgot to answer his most important question: > >> > These numbers suggest that this patch series simultaneously >> > has a negative impact on performance and energy required >> > to retire the workload. Why do it? Even some scenario the total energy cost more, at least the avg watts dropped in that scenarios. Len said he has low p-state which can work there. but that's is different. I had sent some data in another email list to show the difference: The following is 2 times kbuild testing result for 3 kinds condiation on SNB EP box, the middle column is the lowest p-state testing result, we can see, it has the lowest power consumption, also has the lowest performance/watts value. At least for kbuild benchmark, powersaving policy has the best compromise on powersaving and power efficient. Further more, due to cpu boost feature, it has better performance in some scenarios. powersaving + ondemand userspace + fixed 1.2GHz performance+ondemand x = 8 231.318 /75 57 165.063 /166 36 253.552 /63 62 x = 16 280.357 /49 72 174.408 /106 54 296.776 /41 82 x = 32 325.206 /34 90 178.675 /90 62 314.153 /37 86 x = 8 233.623 /74 57 164.507 /168 36 254.775 /65 60 x = 16 272.54 /38 96 174.364 /106 54 297.731 /42 79 x = 32 320.758 /34 91 177.917 /91 61 317.875 /35 89 x = 64 326.837 /33 92 179.037 /90 62 320.615 /36 86 -- Thanks Alex