From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751333AbWAQViQ (ORCPT ); Tue, 17 Jan 2006 16:38:16 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751331AbWAQViQ (ORCPT ); Tue, 17 Jan 2006 16:38:16 -0500 Received: from ind-iport-1.cisco.com ([64.104.129.195]:50954 "EHLO ind-iport-1.cisco.com") by vger.kernel.org with ESMTP id S1751265AbWAQViP convert rfc822-to-8bit (ORCPT ); Tue, 17 Jan 2006 16:38:15 -0500 X-MimeOLE: Produced By Microsoft Exchange V6.5 Content-class: urn:content-classes:message MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 8BIT Subject: RE: [PATCH 000 of 5] md: Introduction Date: Wed, 18 Jan 2006 05:38:12 +0800 Message-ID: <26A66BC731DAB741837AF6B2E29C1017D47EA0@xmb-hkg-413.apac.cisco.com> X-MS-Has-Attach: X-MS-TNEF-Correlator: Thread-Topic: [PATCH 000 of 5] md: Introduction Thread-Index: AcYbPoFG1hT232E5T7+cn3cansTrMwAb1Yqg From: "Lincoln Dale \(ltd\)" To: "Michael Tokarev" , "NeilBrown" Cc: , , "Steinar H. Gunderson" X-OriginalArrivalTime: 17 Jan 2006 21:38:03.0858 (UTC) FILETIME=[4BEADB20:01C61BAE] Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org > Neil, is this online resizing/reshaping really needed? I understand > all those words means alot for marketing persons - zero downtime, > online resizing etc, but it is much safer and easier to do that stuff > 'offline', on an inactive array, like raidreconf does - safer, easier, > faster, and one have more possibilities for more complex changes. It > isn't like you want to add/remove drives to/from your arrays every day... > Alot of good hw raid cards are unable to perform such reshaping too. RAID resize/restripe may not be so common with cheap / PC-based RAID systems, but it is common with midrange and enterprise storage subsystems from vendors such as EMC, HDS, IBM & HP. in fact, I'd say it's the exception to the rule _if_ an midrange/enterprise storage subsystem doesn't have an _online_ resize capability.. personally, I think this this useful functionality, but my personal preference is that this would be in DM/LVM2 rather than MD. but given Neil is the MD author/maintainer, I can see why he'd prefer to do it in MD. :) cheers, lincoln.