From: Andreas Dilger Subject: Re: booked-page-flag.patch Date: Fri, 16 Feb 2007 05:14:08 -0700 Message-ID: <20070216121408.GQ10715@schatzie.adilger.int> References: <20070215004504.023a90f0.akpm@linux-foundation.org> <45D495EA.3060200@redhat.com> <20070215125654.b0f18ab3.akpm@linux-foundation.org> <20070215152352.6ddcfa92.akpm@linux-foundation.org> <20070215234640.d52e5908.akpm@linux-foundation.org> <20070216000606.08372d6f.akpm@linux-foundation.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Alex Tomas , Eric Sandeen , Theodore Ts'o , "linux-ext4@vger.kernel.org" To: Andrew Morton Return-path: Received: from mail.clusterfs.com ([206.168.112.78]:43583 "EHLO mail.clusterfs.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751450AbXBPMOK (ORCPT ); Fri, 16 Feb 2007 07:14:10 -0500 Content-Disposition: inline In-Reply-To: <20070216000606.08372d6f.akpm@linux-foundation.org> Sender: linux-ext4-owner@vger.kernel.org List-Id: linux-ext4.vger.kernel.org On Feb 16, 2007 00:06 -0800, Andrew Morton wrote: > On Fri, 16 Feb 2007 10:56:55 +0300 Alex Tomas wrote: > > well, even so we need to reserve not that block ony, but > > also needed metadata (for the worst case). > > Right. Reserve all the blocks for the page and all the metadata for a page > at that file offset. Worst case. This only really becomes an issue when the filesystem (+reservations) is close to being full. If we are close enough to worry about running out of space we can also refuse to do delayed allocation. Cheers, Andreas -- Andreas Dilger Principal Software Engineer Cluster File Systems, Inc.