Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932125AbYGQQEc (ORCPT ); Thu, 17 Jul 2008 12:04:32 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1756410AbYGQQEX (ORCPT ); Thu, 17 Jul 2008 12:04:23 -0400 Received: from smtp.eu.citrix.com ([62.200.22.115]:52863 "EHLO SMTP.EU.CITRIX.COM" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755043AbYGQQEW convert rfc822-to-8bit (ORCPT ); Thu, 17 Jul 2008 12:04:22 -0400 X-IronPort-AV: E=Sophos;i="4.31,204,1215388800"; d="scan'208";a="1061975" X-MimeOLE: Produced By Microsoft Exchange V6.5 Content-class: urn:content-classes:message MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 8BIT Subject: RE: Large increase in context switch rate Date: Thu, 17 Jul 2008 17:04:20 +0100 Message-ID: <0E902970173AF84089673FA54B7FE78A32906C@lonpexch01.citrite.net> In-Reply-To: <487F6913.2000602@goop.org> X-MS-Has-Attach: X-MS-TNEF-Correlator: Thread-Topic: Large increase in context switch rate Thread-Index: AcjoJCliOfdZ9QeeQNap3DTg4zs5aAAAOP2Q References: <487E43D9.7080703@goop.org> <1216286250.5232.67.camel@twins> <487F5F15.4050208@goop.org> <0E902970173AF84089673FA54B7FE78A32906B@lonpexch01.citrite.net> <487F6913.2000602@goop.org> From: "Alex Nixon (Intern)" To: "Jeremy Fitzhardinge" Cc: "Peter Zijlstra" , "Ingo Molnar" , "Linux Kernel Mailing List" , "Ian Campbell" X-OriginalArrivalTime: 17 Jul 2008 16:04:21.0248 (UTC) FILETIME=[C63F0800:01C8E826] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1246 Lines: 40 I'm talking about total number of context switches - kernbench gets it from time -f "%c" make -j 4 Dividing through it gives me a rate of around 250/sec (vs Peters 3000), but I've set CONFIG_HZ=100 (vs Peters 1000), so they don't wildly conflict. Well spotted :-) - Alex -----Original Message----- From: Jeremy Fitzhardinge [mailto:jeremy@goop.org] Sent: 17 July 2008 16:45 To: Alex Nixon (Intern) Cc: Peter Zijlstra; Ingo Molnar; Linux Kernel Mailing List; Ian Campbell Subject: Re: Large increase in context switch rate Alex Nixon (Intern) wrote: > Yeah I've checked - the number of context switches seems to be around > 60k regardless of whether CONFIG_PARAVIRT is switched on, and regardless > of whether it's running in domu or native (-j4 on dual core) > OK, just to be sure we're talking about the same thing, is kernbench displaying the context switch *rate*, or the total number of context switches during the build? Peter is looking at vmstat, which is showing cs/sec. J -- 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/