From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S264290AbTDKBht (for ); Thu, 10 Apr 2003 21:37:49 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S264253AbTDKBht (for ); Thu, 10 Apr 2003 21:37:49 -0400 Received: from [12.47.58.73] ([12.47.58.73]:8038 "EHLO pao-ex01.pao.digeo.com") by vger.kernel.org with ESMTP id S264290AbTDKBhs (for ); Thu, 10 Apr 2003 21:37:48 -0400 Date: Thu, 10 Apr 2003 18:50:06 -0700 From: Andrew Morton To: Hanna Linder Cc: linux-kernel@vger.kernel.org Subject: Re: [Lockmeter 2.5] BKL with 51ms hold time, prove me wrong Message-Id: <20030410185006.5fd88c30.akpm@digeo.com> In-Reply-To: <46950000.1050023701@w-hlinder> References: <46950000.1050023701@w-hlinder> X-Mailer: Sylpheed version 0.8.9 (GTK+ 1.2.10; i586-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-OriginalArrivalTime: 11 Apr 2003 01:49:24.0140 (UTC) FILETIME=[940286C0:01C2FFCC] Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Hanna Linder wrote: > > > My original purpose was to verify my lockmeter port is producing > valid data so I was comparing to readprofile results. However, I saw > these high hold times and wanted to show them to you. Here is the > whole lockmeter output file: > http://prdownloads.sourceforge.net/lse/lockmeter.rmapm > > Below is a snippet of lockmeter data from running Andrew Morton's > rmap-test -m -i 10 -n 50 -s 600 -t 100 foo > on a 2-way PIII 256MB RAM 500MHz System I'm a bit surprised that even slow machine like that would take 50 milliseconds to truncate 128MB of file, but it's not impossible I guess. Truncate is not really a fastpath. ext3 in -mm doesn't have any lock_kernels in it.