From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1750792AbWGKNyL (ORCPT ); Tue, 11 Jul 2006 09:54:11 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1750794AbWGKNyL (ORCPT ); Tue, 11 Jul 2006 09:54:11 -0400 Received: from e5.ny.us.ibm.com ([32.97.182.145]:4817 "EHLO e5.ny.us.ibm.com") by vger.kernel.org with ESMTP id S1750792AbWGKNyJ (ORCPT ); Tue, 11 Jul 2006 09:54:09 -0400 Date: Tue, 11 Jul 2006 09:54:30 -0400 From: Mike Grundy To: Heiko Carstens Cc: Martin Schwidefsky , Jan Glauber , linux-kernel@vger.kernel.org, systemtap@sources.redhat.com Subject: Re: [PATCH] kprobes for s390 architecture Message-ID: <20060711135430.GA5070@localhost.localdomain> Mail-Followup-To: Heiko Carstens , Martin Schwidefsky , Jan Glauber , linux-kernel@vger.kernel.org, systemtap@sources.redhat.com References: <20060623150344.GL9446@osiris.boeblingen.de.ibm.com> <20060623222106.GA25410@osiris.ibm.com> <20060624113641.GB10403@osiris.ibm.com> <1151421789.5390.65.camel@localhost> <20060628055857.GA9452@osiris.boeblingen.de.ibm.com> <20060707172333.GA12068@localhost.localdomain> <20060707172555.GA10452@osiris.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20060707172555.GA10452@osiris.ibm.com> User-Agent: Mutt/1.4.2.1i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Jul 07, 2006 at 07:25:55PM +0200, Heiko Carstens wrote: > > ok, I tried, but my "better ideas" made things worse. stop_machine_run() wins: > How fast is this if you have to exchange several hundred instructions? I did a little measuring. On average stop_machine_run() adds 8.7 msec of overhead on a 4-way config. Of that %57 was sub-msec overhead. For the times where overhead was measurable, the average was 20.2 msec, lowest at 10msec highest at 100msec. That's on a z800 under vm and I have no idea how many real cpus the machine has :-) -- Thanks Mike ========================================= Michael Grundy - grundym@us.ibm.com Advanced Linux Response Team (ALRT) http://ltc.linux.ibm.com/teamweb/alrt/ 845-435-8842 (T/L 295) If at first you don't succeed, call in an air strike.