From mboxrd@z Thu Jan  1 00:00:00 1970
Received: from eggs.gnu.org ([140.186.70.92]:44731)
	by lists.gnu.org with esmtp (Exim 4.71)
	(envelope-from <stefanha@gmail.com>) id 1RXx3b-00054N-Ta
	for qemu-devel@nongnu.org; Tue, 06 Dec 2011 10:35:51 -0500
Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71)
	(envelope-from <stefanha@gmail.com>) id 1RXx3T-000215-Vx
	for qemu-devel@nongnu.org; Tue, 06 Dec 2011 10:35:47 -0500
Received: from mail-ww0-f53.google.com ([74.125.82.53]:46713)
	by eggs.gnu.org with esmtp (Exim 4.71)
	(envelope-from <stefanha@gmail.com>) id 1RXx3T-00020x-Ib
	for qemu-devel@nongnu.org; Tue, 06 Dec 2011 10:35:39 -0500
Received: by wgbds1 with SMTP id ds1so6498486wgb.10
	for <qemu-devel@nongnu.org>; Tue, 06 Dec 2011 07:35:38 -0800 (PST)
MIME-Version: 1.0
In-Reply-To: <CAGtkxYyj-CTy26W2Bu8L6GuWV6Xd5CHkknQYc3HieyXooey4bQ@mail.gmail.com>
References: <4EDDDB5A.8020102@linux.vnet.ibm.com>
	<CAJSP0QWnt2At2-wcXCi82ugZmry4wHe=ZpSYtJbRwh09B5bjUw@mail.gmail.com>
	<4EDDE7E4.1020503@linux.vnet.ibm.com>
	<CAJSP0QX6o_JT6VthjYHeCFV0Nkku+-6Qxg_27hn5CbX_-t9VvA@mail.gmail.com>
	<CAGtkxYyj-CTy26W2Bu8L6GuWV6Xd5CHkknQYc3HieyXooey4bQ@mail.gmail.com>
Date: Tue, 6 Dec 2011 15:35:38 +0000
Message-ID: <CAJSP0QUm6g_9zAO2JpgjGNzyMEUAcpyLjXW2MGFQTnH_s-sQyQ@mail.gmail.com>
From: Stefan Hajnoczi <stefanha@gmail.com>
Content-Type: text/plain; charset=GB2312
Content-Transfer-Encoding: quoted-printable
Subject: Re: [Qemu-devel] About the snapshot
List-Id: <qemu-devel.nongnu.org>
List-Unsubscribe: <https://lists.nongnu.org/mailman/options/qemu-devel>,
	<mailto:qemu-devel-request@nongnu.org?subject=unsubscribe>
List-Archive: <http://lists.nongnu.org/archive/html/qemu-devel>
List-Post: <mailto:qemu-devel@nongnu.org>
List-Help: <mailto:qemu-devel-request@nongnu.org?subject=help>
List-Subscribe: <https://lists.nongnu.org/mailman/listinfo/qemu-devel>,
	<mailto:qemu-devel-request@nongnu.org?subject=subscribe>
To: Zhi Hui Li <zhihuili@linux.vnet.ibm.com>
Cc: qemu-devel@nongnu.org

2011/12/6 Zhi Hui Li <zhihuili@linux.vnet.ibm.com>:
>
>
> 2011/12/6 Stefan Hajnoczi <stefanha@gmail.com>
>>
>> On Tue, Dec 6, 2011 at 10:01 AM, Zhi Hui Li <zhihuili@linux.vnet.ibm.com=
>
>> wrote:
>> > On 2011=C4=EA12=D4=C206=C8=D5 17:40, Stefan Hajnoczi wrote:
>> >>
>> >> On Tue, Dec 6, 2011 at 9:07 AM, Zhi Hui Li<zhihuili@linux.vnet.ibm.co=
m>
>> >>  wrote:
>> >>>
>> >>>
>> >>> 1) :
>> >>>
>> >>> for example:
>> >>>
>> >>> BDRVQcowState *s =3D bs->opaque;
>> >>>
>> >>> s->snapshots
>> >>> s->nb_snapshots
>> >>>
>> >>>
>> >>> 1:use the command:   qemu-img snapshot ./test.qcow2  -c aa
>> >>> the memory of the s->snapshot don't free,
>> >>> if the s->nb_snapshots is large, Does it have some problems.
>> >>>
>> >>> 2: use the command:  qemu-system-x86_64  ./test.qcow2 -snapshot
>> >>> when the program ends, Does it need to free the s->snapshots ?
>> >>
>> Okay, I think you're saying that in #1 s->snapshots is leaked because
>> qcow2_free_snapshots() is not being called from qcow2_close().
>>
>> Do you want to send a patch to fix this?
>
>
> Ok, I will send a patch  tomorrow.
> But I think in the #2  it also need to call qcow2_free_snapshots() , if y=
ou
> have called several times savevm,
> the s->snapshots will very large, when the process end, it also need to
> free.

Right, I think I understand what you're saying.  I was thinking about
what #1 and #2 mean differently, but it doesn't matter.

If qcow2_close() frees s->snapshots then the problem is solved in all
possible qcow2 use cases, including #2 with savevm.

Stefan