From mboxrd@z Thu Jan 1 00:00:00 1970 From: bugzilla-daemon@bugzilla.kernel.org Subject: [Bug 20902] High IO wait when writing to ext4 Date: Fri, 29 Oct 2010 16:23:41 GMT Message-ID: <201010291623.o9TGNfZ7018396@demeter1.kernel.org> References: Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" To: linux-ext4@vger.kernel.org Return-path: Received: from demeter.kernel.org ([140.211.167.39]:53519 "EHLO demeter1.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757613Ab0J2QXm (ORCPT ); Fri, 29 Oct 2010 12:23:42 -0400 Received: from demeter1.kernel.org (localhost.localdomain [127.0.0.1]) by demeter1.kernel.org (8.14.4/8.14.3) with ESMTP id o9TGNfLC018397 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO) for ; Fri, 29 Oct 2010 16:23:41 GMT In-Reply-To: Sender: linux-ext4-owner@vger.kernel.org List-ID: https://bugzilla.kernel.org/show_bug.cgi?id=20902 Justin Maggard changed: What |Removed |Added ---------------------------------------------------------------------------- CC| |jmaggard10@gmail.com --- Comment #9 from Justin Maggard 2010-10-29 16:23:36 --- I just ran into something similar a few days ago. It was a 4TB filesystem with about 50,000 files in a mixed data set. I ran a test script that unmounted, remounted, and then started writing 64MB files in a loop using dd. With delalloc on, the third 64MB write after umount/mount always took about 150 seconds. With delalloc off, the first write always took ~150 seconds. Writes after that were a fraction of a seconds. -- Configure bugmail: https://bugzilla.kernel.org/userprefs.cgi?tab=email ------- You are receiving this mail because: ------- You are watching the assignee of the bug.