From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:54522) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1UomDR-0004wf-Nj for qemu-devel@nongnu.org; Mon, 17 Jun 2013 23:04:19 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1UomDQ-0004py-H3 for qemu-devel@nongnu.org; Mon, 17 Jun 2013 23:04:17 -0400 Received: from e28smtp09.in.ibm.com ([122.248.162.9]:50230) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1UomDP-0004kk-VA for qemu-devel@nongnu.org; Mon, 17 Jun 2013 23:04:16 -0400 Received: from /spool/local by e28smtp09.in.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Tue, 18 Jun 2013 08:29:22 +0530 Received: from d28relay04.in.ibm.com (d28relay04.in.ibm.com [9.184.220.61]) by d28dlp03.in.ibm.com (Postfix) with ESMTP id 265761258051 for ; Tue, 18 Jun 2013 08:32:46 +0530 (IST) Received: from d28av02.in.ibm.com (d28av02.in.ibm.com [9.184.220.64]) by d28relay04.in.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id r5I33hk025362444 for ; Tue, 18 Jun 2013 08:33:44 +0530 Received: from d28av02.in.ibm.com (loopback [127.0.0.1]) by d28av02.in.ibm.com (8.14.4/8.13.1/NCO v10.0 AVout) with ESMTP id r5I33lUK023787 for ; Tue, 18 Jun 2013 13:03:47 +1000 Message-ID: <51BFCE0E.5050408@linux.vnet.ibm.com> Date: Tue, 18 Jun 2013 11:03:42 +0800 From: Wenchao Xia MIME-Version: 1.0 References: <1371124063-12971-1-git-send-email-kwolf@redhat.com> In-Reply-To: <1371124063-12971-1-git-send-email-kwolf@redhat.com> Content-Type: text/plain; charset=GB2312 Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH 0/5] qcow2: Discard freed clusters List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Kevin Wolf Cc: qemu-devel@nongnu.org, stefanha@redhat.com Hi, Kevin In normal case, qcow2 is based on raw-posix file which don't support discard operation, so this serial doesn't change much in this case, still real space is not freed in snapshot delete, and it completes fast. Instead, tt affects the case that some protocol below support discard, so delete will be more clean but slower in that case. Is this true? Maybe add this in commit message? > This series adds options to make qcow2 discard freed clusters, in several > categories. By default, only freed clusters related to snapshots (i.e. mainly > snapshot deletion) are discarded. > > Kevin Wolf (5): > Revert "block: Disable driver-specific options for 1.5" > qcow2: Add refcount update reason to all callers > qcow2: Options to enable discard for freed clusters > qcow2: Batch discards > block: Always enable discard on the protocol level > > block.c | 2 +- > block/qcow2-cluster.c | 38 +++++++++---- > block/qcow2-refcount.c | 139 ++++++++++++++++++++++++++++++++++++++++------- > block/qcow2-snapshot.c | 6 +- > block/qcow2.c | 30 +++++++++- > block/qcow2.h | 32 ++++++++++- > blockdev.c | 118 ++-------------------------------------- > tests/qemu-iotests/group | 2 +- > 8 files changed, 214 insertions(+), 153 deletions(-) > -- Best Regards Wenchao Xia