From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1041933AbdDVG3P (ORCPT ); Sat, 22 Apr 2017 02:29:15 -0400 Received: from cmta20.telus.net ([209.171.16.93]:57526 "EHLO cmta20.telus.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1041421AbdDVG3N (ORCPT ); Sat, 22 Apr 2017 02:29:13 -0400 X-Authority-Analysis: v=2.2 cv=Nv4+S4VJ c=1 sm=1 tr=0 a=zJWegnE7BH9C0Gl4FFgQyA==:117 a=zJWegnE7BH9C0Gl4FFgQyA==:17 a=Pyq9K9CWowscuQLKlpiwfMBGOR0=:19 a=8nJEP1OIZ-IA:10 a=VwQbUJbxAAAA:8 a=oR0TowyIA3Eg0opGEDYA:9 a=wPNLvfGTeEIA:10 a=AjGcO6oz07-iQ99wixmX:22 From: "Doug Smythies" To: "'Rafael J. Wysocki'" Cc: "'Mel Gorman'" , "'Rafael Wysocki'" , "=?iso-8859-1?Q?'J=F6rg_Otte'?=" , "'Linux Kernel Mailing List'" , "'Linux PM'" , "'Srinivas Pandruvada'" , "Doug Smythies" References: <20170410084117.rjh3mtdx7hd2i5ze@techsingularity.net> <003101d2b573$16b28370$44178a50$@net> <000a01d2b9e6$393afef0$abb0fcd0$@net> 1NIWdcLHYgvfQ1NIbds8qh In-Reply-To: 1NIWdcLHYgvfQ1NIbds8qh Subject: RE: Performance of low-cpu utilisation benchmark regressed severely since 4.6 Date: Fri, 21 Apr 2017 23:29:06 -0700 Message-ID: <000301d2bb31$c0037790$400a66b0$@net> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit X-Mailer: Microsoft Office Outlook 12.0 Thread-Index: AdK6PfAIdlImqF/HSEGEaEuacqZgtAA8MWHg Content-Language: en-ca X-CMAE-Envelope: MS4wfCHmGwajNQRm6JxM9ccPozKooBbxuLR1cseCsijuk+w1b8iNCdNWgXP8suy99AIT33sgC/EoChKQwBSAXkh0Vs8YefDCNPBcezGEFEJqIhdsoCxBSjAK j6c9+QvZvyIRXWD99LcTxF3ICAAglLudv4s/1PicKHnb1FQhyHgwstk0lrFAbhcdiZNBZGqCGcxdscekyQBOG8DzDVdXG95xVnMEkMlvxd197SPtmCNtyyVR W7plfUcZjqBoE9FnJSNzl2EDiHljV+lzxAjXe4Iuk/TlXn6pddOsBquEN1tmEjXFal+J/3WGGaMTFn6bK6m5EX+J4Yopi03qPBU85tDh+wlk2Hak0QeMR9wd 4XfPud033dD69bIewkdDIsL5xp3H/M6yIQ1FAhxJa3WDEm1sIpmqk7YX2z1oUQIrOqwYpu8/ Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2017.04.20 18:18 Rafael wrote: > On Thursday, April 20, 2017 07:55:57 AM Doug Smythies wrote: >> On 2017.04.19 01:16 Mel Gorman wrote: >>> On Fri, Apr 14, 2017 at 04:01:40PM -0700, Doug Smythies wrote: >>>> Hi Mel, > > [cut] > >>> And the revert does help albeit not being an option for reasons Rafael >>> covered. >> >> New data point: Kernel 4.11-rc7 intel_pstate, powersave forcing the >> load based algorithm: Elapsed 3178 seconds. >> >> If I understand your data correctly, my load based results are the opposite of yours. >> >> Mel: 4.11-rc5 vanilla: Elapsed mean: 3750.20 Seconds >> Mel: 4.11-rc5 load based: Elapsed mean: 2503.27 Seconds >> Or: 33.25% >> >> Doug: 4.11-rc6 stock: Elapsed total (5 runs): 2364.45 Seconds >> Doug: 4.11-rc7 force load based: Elapsed total (5 runs): 3178 Seconds >> Or: -34.4% > > I wonder if you can do the same thing I've just advised Mel to do. That is, > take my linux-next branch: > > git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm.git linux-next > > (which is new material for 4.12 on top of 4.11-rc7) and reduce > INTEL_PSTATE_DEFAULT_SAMPLING_INTERVAL (in intel_pstate.c) in it by 1/2 > (force load-based if need be, I'm not sure what PM profile of your test system > is). I did not need to force load-based. I do not know how to figure it out from an acpidump the way Srinivas does. I did a trace and figured out what algorithm it was using from the data. Reference test, before changing INTEL_PSTATE_DEFAULT_SAMPLING_INTERVAL: 3239.4 seconds. Test after changing INTEL_PSTATE_DEFAULT_SAMPLING_INTERVAL: 3195.5 seconds. By far, and with any code, I get the fastest elapsed time, of course next to performance mode, but not by much, by limiting the test to only use just 1 cpu: 1814.2 Seconds. (performance governor, restated from a previous e-mail: 1776.05 seconds) ... Doug