From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1761387Ab3DBIex (ORCPT ); Tue, 2 Apr 2013 04:34:53 -0400 Received: from mout.gmx.net ([212.227.15.18]:56466 "EHLO mout.gmx.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1760435Ab3DBIeu (ORCPT ); Tue, 2 Apr 2013 04:34:50 -0400 X-Authenticated: #14349625 X-Provags-ID: V01U2FsdGVkX19Xc/tNJxxX/2k0QcwRz6McN+p4KaTkwwJT9dcfCd gm+BxkBR8o2Xre Message-ID: <1364891674.4976.65.camel@marge.simpson.net> Subject: Re: [patch v3 0/8] sched: use runnable avg in load balance From: Mike Galbraith To: Michael Wang Cc: Alex Shi , mingo@redhat.com, peterz@infradead.org, tglx@linutronix.de, akpm@linux-foundation.org, arjan@linux.intel.com, bp@alien8.de, pjt@google.com, namhyung@kernel.org, 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 Date: Tue, 02 Apr 2013 10:34:34 +0200 In-Reply-To: <515A877B.3020908@linux.vnet.ibm.com> References: <1364873008-3169-1-git-send-email-alex.shi@intel.com> <515A877B.3020908@linux.vnet.ibm.com> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.2.3 Content-Transfer-Encoding: 7bit Mime-Version: 1.0 X-Y-GMX-Trusted: 0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 2013-04-02 at 15:23 +0800, Michael Wang wrote: > On 04/02/2013 11:23 AM, Alex Shi wrote: > [snip] > > > > [patch v3 1/8] Revert "sched: Introduce temporary FAIR_GROUP_SCHED > > [patch v3 2/8] sched: set initial value of runnable avg for new > > [patch v3 3/8] sched: only count runnable avg on cfs_rq's nr_running > > [patch v3 4/8] sched: update cpu load after task_tick. > > [patch v3 5/8] sched: compute runnable load avg in cpu_load and > > [patch v3 6/8] sched: consider runnable load average in move_tasks > > [patch v3 7/8] sched: consider runnable load average in > > [patch v3 8/8] sched: use instant load for burst wake up > > I've tested the patch set on 12 cpu X86 box with 3.9.0-rc2, and pgbench > show regression on high-end this time. > > | db_size | clients | tps | | tps | > +---------+---------+-------+ +-------+ > | 22 MB | 1 | 10662 | | 10446 | > | 22 MB | 2 | 21483 | | 20887 | > | 22 MB | 4 | 42046 | | 41266 | > | 22 MB | 8 | 55807 | | 51987 | > | 22 MB | 12 | 50768 | | 50974 | > | 22 MB | 16 | 49880 | | 49510 | > | 22 MB | 24 | 45904 | | 42398 | > | 22 MB | 32 | 43420 | | 40995 | > | 7484 MB | 1 | 7965 | | 7376 | > | 7484 MB | 2 | 19354 | | 19149 | > | 7484 MB | 4 | 37552 | | 37458 | > | 7484 MB | 8 | 48655 | | 46618 | > | 7484 MB | 12 | 45778 | | 45756 | > | 7484 MB | 16 | 45659 | | 44911 | > | 7484 MB | 24 | 42192 | | 37185 | -11.87% > | 7484 MB | 32 | 36385 | | 34447 | > | 15 GB | 1 | 7677 | | 7359 | > | 15 GB | 2 | 19227 | | 19049 | > | 15 GB | 4 | 37335 | | 36947 | > | 15 GB | 8 | 48130 | | 46898 | > | 15 GB | 12 | 45393 | | 43986 | > | 15 GB | 16 | 45110 | | 45719 | > | 15 GB | 24 | 41415 | | 36813 | -11.11% > | 15 GB | 32 | 35988 | | 34025 | > > The reason may caused by wake_affine()'s higher overhead, and pgbench is > really sensitive to this stuff... For grins, you could try running the whole thing SCHED_BATCH. (/me sees singing/dancing red herring whenever wake_affine() and pgbench appear in the same sentence;) -Mike