From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S264833AbUHMMIZ (ORCPT ); Fri, 13 Aug 2004 08:08:25 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S264912AbUHMMIY (ORCPT ); Fri, 13 Aug 2004 08:08:24 -0400 Received: from zero.aec.at ([193.170.194.10]:29445 "EHLO zero.aec.at") by vger.kernel.org with ESMTP id S264833AbUHMMIX (ORCPT ); Fri, 13 Aug 2004 08:08:23 -0400 To: Ingo Molnar cc: linux-kernel@vger.kernel.org Subject: Re: [patch] Latency Tracer, voluntary-preempt-2.6.8-rc4-O6 References: <2m9bF-kH-13@gated-at.bofh.it> <2m9EG-Js-5@gated-at.bofh.it> <2md5B-36u-11@gated-at.bofh.it> <2mkTt-BZ-11@gated-at.bofh.it> <2nrJd-7Dx-19@gated-at.bofh.it> <2ouFe-2vz-63@gated-at.bofh.it> <2rfT9-5wi-17@gated-at.bofh.it> <2rF1c-6Iy-7@gated-at.bofh.it> <2sxEs-46P-1@gated-at.bofh.it> <2sCkH-7i5-15@gated-at.bofh.it> <2sHu9-2EW-31@gated-at.bofh.it> From: Andi Kleen Date: Fri, 13 Aug 2004 14:08:17 +0200 In-Reply-To: <2sHu9-2EW-31@gated-at.bofh.it> (Ingo Molnar's message of "Fri, 13 Aug 2004 12:30:17 +0200") Message-ID: User-Agent: Gnus/5.110003 (No Gnus v0.3) Emacs/21.2 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Ingo Molnar writes: > * Lee Revell wrote: > >> Interesting results. One of the problems is kallsyms_lookup, >> triggered by the printks: > > yeah - kallsyms_lookup does a linear search over thousands of symbols. > Especially since /proc/latency_trace uses it too it would be worthwile > to implement some sort of binary searching. Or just stick some cond_sched()s in there. It was designed to be slow, but there are no locking issues. -Andi