From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S265271AbUFXOGJ (ORCPT ); Thu, 24 Jun 2004 10:06:09 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S265290AbUFXOGJ (ORCPT ); Thu, 24 Jun 2004 10:06:09 -0400 Received: from holomorphy.com ([207.189.100.168]:65161 "EHLO holomorphy.com") by vger.kernel.org with ESMTP id S265271AbUFXOGE (ORCPT ); Thu, 24 Jun 2004 10:06:04 -0400 Date: Thu, 24 Jun 2004 07:05:39 -0700 From: William Lee Irwin III To: Andi Kleen Cc: Yusuf Goolamabbas , linux-kernel@vger.kernel.org Subject: Re: finish_task_switch high in profiles in 2.6.7 Message-ID: <20040624140539.GT1552@holomorphy.com> Mail-Followup-To: William Lee Irwin III , Andi Kleen , Yusuf Goolamabbas , linux-kernel@vger.kernel.org References: <2ayz2-1Um-15@gated-at.bofh.it> <20040624104416.GB8798@outblaze.com> <20040624113608.GA31080@colin2.muc.de> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20040624113608.GA31080@colin2.muc.de> User-Agent: Mutt/1.5.5.1+cvs20040105i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Jun 24, 2004 at 01:36:08PM +0200, Andi Kleen wrote: > Sounds like a inferior clone of dprobes to me. But I doubt it > would help tracking this down. The schedprof thing I wrote to track down the source of context switches during database creation may prove useful, since it has at least demonstrated where thundering herds came from properly once before and is damn near idiotproof -- it requires no more than readprofile(1) from userspace. I'll dredge that up again and maybe we'll see if it helps here. It will also properly point to sys_sched_yield() and the like in the event of badly-behaved userspace. -- wli