Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1422644Ab3CVQaI (ORCPT ); Fri, 22 Mar 2013 12:30:08 -0400 Received: from e35.co.us.ibm.com ([32.97.110.153]:46076 "EHLO e35.co.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1160996Ab3CVQaH (ORCPT ); Fri, 22 Mar 2013 12:30:07 -0400 Date: Fri, 22 Mar 2013 09:28:20 -0700 From: "Paul E. McKenney" To: Christoph Lameter Cc: Steven Rostedt , Frederic Weisbecker , Rob Landley , linux-kernel@vger.kernel.org, josh@joshtriplett.org, zhong@linux.vnet.ibm.com, khilman@linaro.org, geoff@infradead.org, tglx@linutronix.de Subject: Re: [PATCH] nohz1: Documentation Message-ID: <20130322162820.GN3637@linux.vnet.ibm.com> Reply-To: paulmck@linux.vnet.ibm.com References: <20130318222548.GG3656@linux.vnet.ibm.com> <1363822338.6345.33.camel@gandalf.local.home> <20130320235545.GL3637@linux.vnet.ibm.com> <0000013d8db514e4-bf492080-82c9-412a-90b8-54ddc1463e4b-000000@email.amazonses.com> <20130321171518.GW3637@linux.vnet.ibm.com> <0000013d8e3f58ce-0f6ea95f-780a-49c1-a633-5aa0cf3e5040-000000@email.amazonses.com> <20130321185821.GF3637@linux.vnet.ibm.com> <0000013d8e8d24fd-d2931c45-2722-46d1-8b47-2ef11e21096d-000000@email.amazonses.com> <20130321205054.GI3637@linux.vnet.ibm.com> <0000013d9289cebc-e6380265-3a74-4343-b851-765f785a3754-000000@email.amazonses.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <0000013d9289cebc-e6380265-3a74-4343-b851-765f785a3754-000000@email.amazonses.com> User-Agent: Mutt/1.5.21 (2010-09-15) X-TM-AS-MML: No X-Content-Scanned: Fidelis XPS MAILER x-cbid: 13032216-4834-0000-0000-000004FBCCB4 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 814 Lines: 20 On Fri, Mar 22, 2013 at 02:38:58PM +0000, Christoph Lameter wrote: > On Thu, 21 Mar 2013, Paul E. McKenney wrote: > > > So, how long of busy periods are you contemplating for your SCHED_FIFO > > threads? Is it possible to tune/adjust the offending per-CPU ktheads > > to wake up less frequently than that time? > > Test programs right now run 10 seconds. 30 seconds would definitely be > enough for the worst case. OK, that might be doable for some workloads. What happens when you try tuning the 2-second wakeup interval to (say) 45 seconds? Thanx, Paul -- 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/