From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ted Ts'o Subject: Re: High CPU Utilization When Copying to Ext4 Date: Fri, 8 Jul 2011 14:24:25 -0400 Message-ID: <20110708182425.GC3331@thunk.org> References: <341DAA96EE3A8444B6E4657BE8A846EA4B3DA126FE@NDJSSCC06.ndc.nasa.gov> <20110627030539.GF3064@thunk.org> <341DAA96EE3A8444B6E4657BE8A846EA4B3DA12708@NDJSSCC06.ndc.nasa.gov> <341DAA96EE3A8444B6E4657BE8A846EA4B3DA1270A@NDJSSCC06.ndc.nasa.gov> <50F503A1-6A16-41C4-9C27-0662063C7817@mit.edu> <4E0BBCE9.9020600@nasa.gov> <20110630023306.GY2729@thunk.org> <4E17398F.2090609@nasa.gov> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: "linux-ext4@vger.kernel.org" To: Sean McCauliff Return-path: Received: from li9-11.members.linode.com ([67.18.176.11]:47679 "EHLO test.thunk.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753638Ab1GHSY3 (ORCPT ); Fri, 8 Jul 2011 14:24:29 -0400 Content-Disposition: inline In-Reply-To: <4E17398F.2090609@nasa.gov> Sender: linux-ext4-owner@vger.kernel.org List-ID: OK, #1, can you try doing an experiment with "cp -r ", and tell me whether the copy speed is faster or slower, and whether the CPU utilization is faster or slower? Even if it's a bit slower to use cp -r, it will be easier for us to try to reproduce things and to understand what cp -r is doing as opposed to some mystery java program. #2, if you know how to set up ftrace, can you enable the ext4_mballoc_alloc tracepoint and send me a sample output (a few hundred lines will be plenty). The short version is basically: echo 1 > /sys/kernel/debug/tracing/events/ext4/ext4_mballoc_alloc/enable cat /sys/kernel/debug/tracing/trace > /var/tmp/trace-save echo 0 > /sys/kernel/debug/tracing/events/ext4/ext4_mballoc_alloc/enable - Ted