From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1030619AbXDZOWg (ORCPT ); Thu, 26 Apr 2007 10:22:36 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1030628AbXDZOWg (ORCPT ); Thu, 26 Apr 2007 10:22:36 -0400 Received: from saraswathi.solana.com ([198.99.130.12]:48289 "EHLO saraswathi.solana.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1030619AbXDZOWf (ORCPT ); Thu, 26 Apr 2007 10:22:35 -0400 Date: Thu, 26 Apr 2007 10:14:55 -0400 From: Jeff Dike To: Valerie Henson Cc: Nikita Danilov , David Lang , Amit Gud , linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, riel@surriel.com, zab@zabbo.net, arjan@infradead.org, suparna@in.ibm.com, brandon@ifup.org, karunasagark@gmail.com, gud@ksu.edu Subject: Re: [RFC][PATCH] ChunkFS: fs fission for faster fsck Message-ID: <20070426141455.GA6155@c2.user-mode-linux.org> References: <17965.60841.900376.524639@gargle.gargle.HOWL> <17966.23512.363955.141489@gargle.gargle.HOWL> <17967.15531.450627.972572@gargle.gargle.HOWL> <20070425224710.GB16129@nifty> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20070425224710.GB16129@nifty> User-Agent: Mutt/1.4.2.2i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Apr 25, 2007 at 03:47:10PM -0700, Valerie Henson wrote: > Actually, there is an upper limit on the number of continuation > inodes. Each file can have a maximum of one continuation inode per > chunk. (This is why we need to support sparse files.) How about this case: Growing file starts in chunk A. Overflows into chunk B. Delete file in chunk A. Growing file overflows chunk B and spots new free space in chunk A (and nothing anywhere else) Overflows into chunk A Delete file in chunk B. Overflow into chunk B again. Maybe this is not realistic, but in the absence of a mechanism to pull data back from an overflow chunk, it seems at least a theoretical possibility that there could be > 1 continuation inodes per file per chunk. Jeff -- Work email - jdike at linux dot intel dot com