Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752071Ab3FJCBe (ORCPT ); Sun, 9 Jun 2013 22:01:34 -0400 Received: from mga03.intel.com ([143.182.124.21]:63834 "EHLO mga03.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750929Ab3FJCBd (ORCPT ); Sun, 9 Jun 2013 22:01:33 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.87,833,1363158000"; d="scan'208";a="252746973" Message-ID: <51B53375.40102@intel.com> Date: Mon, 10 Jun 2013 10:01:25 +0800 From: Alex Shi User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:15.0) Gecko/20120912 Thunderbird/15.0.1 MIME-Version: 1.0 To: Gu Zheng CC: mingo@redhat.com, peterz@infradead.org, tglx@linutronix.de, akpm@linux-foundation.org, bp@alien8.de, pjt@google.com, namhyung@kernel.org, efault@gmx.de, morten.rasmussen@arm.com, vincent.guittot@linaro.org, preeti@linux.vnet.ibm.com, viresh.kumar@linaro.org, linux-kernel@vger.kernel.org, mgorman@suse.de, riel@redhat.com, wangyun@linux.vnet.ibm.com, Jason Low , Changlong Xie , sgruszka@redhat.com, fweisbec@gmail.com Subject: Re: [patch v8 6/9] sched: compute runnable load avg in cpu_load and cpu_avg_load_per_task References: <1370589652-24549-1-git-send-email-alex.shi@intel.com> <1370589652-24549-7-git-send-email-alex.shi@intel.com> <51B530AE.3020004@cn.fujitsu.com> In-Reply-To: <51B530AE.3020004@cn.fujitsu.com> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1123 Lines: 29 On 06/10/2013 09:49 AM, Gu Zheng wrote: > On 06/07/2013 03:20 PM, Alex Shi wrote: > >> > They are the base values in load balance, update them with rq runnable >> > load average, then the load balance will consider runnable load avg >> > naturally. >> > >> > We also try to include the blocked_load_avg as cpu load in balancing, >> > but that cause kbuild performance drop 6% on every Intel machine, and >> > aim7/oltp drop on some of 4 CPU sockets machines. > Hi Alex, > Could you explain me why including the blocked_load_avg causes performance drop ? Thanks for review! the 9th patch has few explanation. like, after the only task got into sleep in a CPU, there is only blocked_load_avg left, it looks quite big in short time. that, block it get tasks before sleep, drive task to other cpu in periodic balance. So, it cause clear load imbalance. -- Thanks Alex -- 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/