From: "Aneesh Kumar K. V" Subject: Re: Ext2 and ext4 preallocation / mballoc Date: Sat, 06 Mar 2010 20:15:20 +0530 Message-ID: <87ocj1se4f.fsf@linux.vnet.ibm.com> References: Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: QUOTED-PRINTABLE To: =?iso-8859-1?q?Ga=EBtan?= Podevijn , linux-ext4@vger.kernel.org Return-path: Received: from e23smtp09.au.ibm.com ([202.81.31.142]:46755 "EHLO e23smtp09.au.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753185Ab0CFOp1 convert rfc822-to-8bit (ORCPT ); Sat, 6 Mar 2010 09:45:27 -0500 Received: from d23relay05.au.ibm.com (d23relay05.au.ibm.com [202.81.31.247]) by e23smtp09.au.ibm.com (8.14.3/8.13.1) with ESMTP id o26EjPQQ001725 for ; Sun, 7 Mar 2010 01:45:25 +1100 Received: from d23av01.au.ibm.com (d23av01.au.ibm.com [9.190.234.96]) by d23relay05.au.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id o26EdhS41413330 for ; Sun, 7 Mar 2010 01:39:43 +1100 Received: from d23av01.au.ibm.com (loopback [127.0.0.1]) by d23av01.au.ibm.com (8.14.3/8.13.1/NCO v10.0 AVout) with ESMTP id o26EjPRt002743 for ; Sun, 7 Mar 2010 01:45:25 +1100 In-Reply-To: Sender: linux-ext4-owner@vger.kernel.org List-ID: On Wed, 17 Feb 2010 16:46:19 +0100, Ga=C3=ABtan Podevijn wrote: > Hello, >=20 > Reading this http://web.mit.edu/tytso/www/linux/ext2intro.html I > understand that ext2 preallocates 8 blocks when a writing data to a > file. Ext3 uses the windows reservations method, but is that ext3 als= o > preallocates 8 blocks when writing data ? >=20 > Moreover, this page > http://kernelnewbies.org/Ext4#head-b2148d2a96d22a1bd7e376e6c08e4a38d0= 8fb157 > explains that ext3 allocates one block at a time and ext4 uses > multiblock allocation that is, allocates many block in a single syste= m > call. >=20 > What is the difference between preallocation on ext2 (and ext3 ?) and= mballoc ? >=20 >=20 You can find mballoc details at=20 http://ols.fedoraproject.org/OLS/Reprints-2008/kumar-reprint.pdf -aneesh -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" i= n the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html