Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1761924AbYHDGym (ORCPT ); Mon, 4 Aug 2008 02:54:42 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1758909AbYHDGya (ORCPT ); Mon, 4 Aug 2008 02:54:30 -0400 Received: from viefep32-int.chello.at ([62.179.121.50]:36176 "EHLO viefep32-int.chello.at" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1761650AbYHDGy3 (ORCPT ); Mon, 4 Aug 2008 02:54:29 -0400 Subject: Re: VolanoMark regression with 2.6.27-rc1 From: Peter Zijlstra To: Dhaval Giani Cc: "Zhang, Yanmin" , Ingo Molnar , LKML , Srivatsa Vaddagiri , Aneesh Kumar KV , Balbir Singh In-Reply-To: <20080804055339.GB5444@linux.vnet.ibm.com> References: <1217474425.25608.150.camel@ymzhang> <1217489463.25608.157.camel@ymzhang> <1217489949.8157.78.camel@twins> <1217490560.25608.168.camel@ymzhang> <1217551154.25608.169.camel@ymzhang> <20080801051407.GA5232@linux.vnet.ibm.com> <1217826278.25608.198.camel@ymzhang> <20080804052228.GA5444@linux.vnet.ibm.com> <1217828278.25608.206.camel@ymzhang> <20080804055339.GB5444@linux.vnet.ibm.com> Content-Type: text/plain Date: Mon, 04 Aug 2008 08:54:26 +0200 Message-Id: <1217832866.9016.45.camel@twins> Mime-Version: 1.0 X-Mailer: Evolution 2.22.3.1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1440 Lines: 48 On Mon, 2008-08-04 at 11:23 +0530, Dhaval Giani wrote: > Peter, vatsa, any ideas? --- Subject: sched: scale sysctl_sched_shares_ratelimit with nr_cpus David reported that his Niagra spend a little too much time in tg_shares_up(), which considering he has a large cpu count makes sense. So scale the ratelimit value with the number of cpus like we do for other controls as well. Reported-by: David Miller Signed-off-by: Peter Zijlstra --- diff --git a/kernel/sched.c b/kernel/sched.c index 9a76e92..7eddaea 100644 --- a/kernel/sched.c +++ b/kernel/sched.c @@ -809,9 +809,9 @@ const_debug unsigned int sysctl_sched_nr_migrate = 32; /* * ratelimit for updating the group shares. - * default: 0.5ms + * default: 0.25ms */ -const_debug unsigned int sysctl_sched_shares_ratelimit = 500000; +const_debug unsigned int sysctl_sched_shares_ratelimit = 250000; /* * period over which we measure -rt task cpu usage in us. @@ -5732,6 +5732,8 @@ static inline void sched_init_granularity(void) sysctl_sched_latency = limit; sysctl_sched_wakeup_granularity *= factor; + + sysctl_sched_shares_ratelimit *= factor; } #ifdef CONFIG_SMP -- 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/