From: Andreas Dilger Subject: Re: EXT4 >16TB resize2fs support Date: Fri, 30 Oct 2009 09:17:57 -0600 Message-ID: <00E93B30-1C92-4185-8E80-B4AD840183B5@sun.com> References: <150c16850910291454j18db2729m572dc0fe22658f1e@mail.gmail.com> Mime-Version: 1.0 Content-Type: text/plain; CHARSET=US-ASCII; format=flowed Content-Transfer-Encoding: 7BIT Cc: ext4 development To: Justin Maggard Return-path: Received: from sca-es-mail-1.Sun.COM ([192.18.43.132]:42480 "EHLO sca-es-mail-1.sun.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932339AbZJ3PRz (ORCPT ); Fri, 30 Oct 2009 11:17:55 -0400 Received: from fe-sfbay-10.sun.com ([192.18.43.129]) by sca-es-mail-1.sun.com (8.13.7+Sun/8.12.9) with ESMTP id n9UFHvBL005741 for ; Fri, 30 Oct 2009 08:18:00 -0700 (PDT) Received: from conversion-daemon.fe-sfbay-10.sun.com by fe-sfbay-10.sun.com (Sun Java(tm) System Messaging Server 7u2-7.04 64bit (built Jul 2 2009)) id <0KSC007001ZMZY00@fe-sfbay-10.sun.com> for linux-ext4@vger.kernel.org; Fri, 30 Oct 2009 08:17:57 -0700 (PDT) In-reply-to: <150c16850910291454j18db2729m572dc0fe22658f1e@mail.gmail.com> Sender: linux-ext4-owner@vger.kernel.org List-ID: On 2009-10-29, at 15:54, Justin Maggard wrote: > What is the current expected status of resize2fs support with 64-bit > filesystems? Specifically, expanding from <16TB to >16TB. I'm using > the latest code from pu, and seeing some odd things. I'm not sure > what the 64bit feature flag does exactly, but is the transition not > handled properly? This isn't supposed to work at all, and in fact should be disabled. Firstly, the group descriptors are not big enough to hold the 64-bit block addresses unless the filesystem was originally formatted > 16TB. Secondly, the resize code has not been made 64-bit clean. > So... what is expected to work at this point, and what is expected to > be broken with the resize process? Any idea why my fs was shrunk down > to 2.2TB when it was supposed to grow to 18TB? The filesystem size was truncated to a 32-bit value. Cheers, Andreas -- Andreas Dilger Sr. Staff Engineer, Lustre Group Sun Microsystems of Canada, Inc.