Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Fri, 5 Oct 2001 00:37:26 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Fri, 5 Oct 2001 00:37:17 -0400 Received: from e32.co.us.ibm.com ([32.97.110.130]:60354 "EHLO e32.bld.us.ibm.com") by vger.kernel.org with ESMTP id ; Fri, 5 Oct 2001 00:36:59 -0400 Date: Thu, 4 Oct 2001 21:35:07 -0700 From: Mike Kravetz To: Andrea Arcangeli Cc: Linus Torvalds , linux-kernel@vger.kernel.org Subject: Re: Context switch times Message-ID: <20011004213507.B1032@w-mikek2.sequent.com> In-Reply-To: <200110042139.f94Ld5r09675@vindaloo.ras.ucalgary.ca> <20011004.145239.62666846.davem@redhat.com> <20011004175526.C18528@redhat.com> <9piokt$8v9$1@penguin.transmeta.com> <20011004164102.E1245@w-mikek2.des.beaverton.ibm.com> <20011005024526.E724@athlon.random> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.2.5i In-Reply-To: <20011005024526.E724@athlon.random>; from andrea@suse.de on Fri, Oct 05, 2001 at 02:45:26AM +0200 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Oct 05, 2001 at 02:45:26AM +0200, Andrea Arcangeli wrote: > doesn't lmbench wakeup only via pipes? Linux uses the sync-wakeup that > avoids reschedule_idle in such case, to serialize the pipe load in the > same cpu. That's what I thought too. However, kernel profile data of a lmbench run on 2.4.10 reveals that the pipe routines only call the non-synchronous form of wake_up. I believe I reached the same conclusion in the 2.4.7 time frame by instrumenting this code. -- Mike - 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/