From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:49769) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZGsqc-0002sn-Ip for qemu-devel@nongnu.org; Sun, 19 Jul 2015 13:57:59 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ZGsqX-00035E-GY for qemu-devel@nongnu.org; Sun, 19 Jul 2015 13:57:58 -0400 Sender: Paolo Bonzini References: From: Paolo Bonzini Message-ID: <55ABE51C.3020708@redhat.com> Date: Sun, 19 Jul 2015 19:57:48 +0200 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH] block: There in no change in userland tools after resizing qcow2 image except file utility. List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Taeha Kim , qemu-block@nongnu.org Cc: kwolf@redhat.com, =?UTF-8?B?6rmA7YOc7ZWY?= , qemu-devel@nongnu.org On 19/07/2015 10:12, Taeha Kim wrote: > $ ./qemu/qemu-img resize 100G.qcow2 200G > Image resized. > > > $ ./qemu/qemu-img check 100G.qcow2 > No errors were found on the image. > 1638400/3276800 = 50.00% allocated, 0.00% fragmented, 0.00% compressed clusters > Image end offset: 107390894080 You are getting a large qcow2 image because you have specified metadata preallocation. However you can see from "qemu-img check" that the preallocation is lost even with your patch. I think if you try resizing to 102408M for example (very little above the previous size) "qemu-img check" will show corruption after the resize. Paolo