Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S262188AbTHTUHw (ORCPT ); Wed, 20 Aug 2003 16:07:52 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S262191AbTHTUHw (ORCPT ); Wed, 20 Aug 2003 16:07:52 -0400 Received: from fw.osdl.org ([65.172.181.6]:61645 "EHLO mail.osdl.org") by vger.kernel.org with ESMTP id S262188AbTHTUHv (ORCPT ); Wed, 20 Aug 2003 16:07:51 -0400 Date: Wed, 20 Aug 2003 12:53:01 -0700 From: Andrew Morton To: "Chen, Kenneth W" Cc: linux-kernel@vger.kernel.org Subject: Re: posix_fallocate question again Message-Id: <20030820125301.3a1ed0fb.akpm@osdl.org> In-Reply-To: <41F331DBE1178346A6F30D7CF124B24B0183C1A4@fmsmsx409.fm.intel.com> References: <41F331DBE1178346A6F30D7CF124B24B0183C1A4@fmsmsx409.fm.intel.com> X-Mailer: Sylpheed version 0.9.4 (GTK+ 1.2.10; i686-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 940 Lines: 23 "Chen, Kenneth W" wrote: > > This has been brought up by Ulrich more than 3 years ago: > http://marc.theaimsgroup.com/?l=linux-kernel&m=95569775802945&w=2 A decent fallocate() implementation requires that the underlying fs has a permanent representation of blocks which are in an "allocated, uninitialised" state. afaik XFS is the only such filesystem. It's a fair bit of work for what doesn't really sound a very useful feature. Doing it in libc is reasonable. Probably the libc implementation could be improved by using ioctl(FIBMAP) and O_DIRECT to mimimise IO and CPU utilisation. > Is there anytime soon that kernel 2.6 will have such functionality? Nope. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/