From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S265943AbUHVDyQ (ORCPT ); Sat, 21 Aug 2004 23:54:16 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S265981AbUHVDyQ (ORCPT ); Sat, 21 Aug 2004 23:54:16 -0400 Received: from ozlabs.org ([203.10.76.45]:20143 "EHLO ozlabs.org") by vger.kernel.org with ESMTP id S265943AbUHVDyO (ORCPT ); Sat, 21 Aug 2004 23:54:14 -0400 Date: Sun, 22 Aug 2004 13:50:34 +1000 From: Anton Blanchard To: Andrew Morton Cc: John Levon , oprofile-list@lists.sourceforge.net, linux-kernel@vger.kernel.org, jbarnes@sgi.com, phil.el@wanadoo.fr Subject: Re: [PATCH] improve OProfile on many-way systems Message-ID: <20040822035034.GA8702@krispykreme> References: <20040821192630.GA9501@compsoc.man.ac.uk> <20040821135833.6b1774a8.akpm@osdl.org> <20040821232206.GC20175@compsoc.man.ac.uk> <20040821163628.10cfa049.akpm@osdl.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20040821163628.10cfa049.akpm@osdl.org> User-Agent: Mutt/1.5.6+20040803i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org > Anyway. My question was mainly a prod in the antonward direction ;) And Im prepared this time :) An excerpt from my test results a few months ago: > I ran a fork/exit intensive benchmark (sdet) on a big machine. > > No patch: > Enabling oprofile resulted in over a 10 times slow down in performance. > > oprofile1.patch: > About 2% slowdown when oprofile enabled > > oprofile2.patch: > About 5% slowdown when oprofile enabled The final version was actually oprofile3.patch but it had a similar (10 times) gain in sdet performance. So the patch is good stuff. Ive been running it locally for the last few months without a problem. Anton