From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:47872) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1aGS5m-0001Yi-H9 for qemu-devel@nongnu.org; Tue, 05 Jan 2016 08:56:07 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1aGS5j-0006DJ-Bc for qemu-devel@nongnu.org; Tue, 05 Jan 2016 08:56:06 -0500 Received: from mx1.redhat.com ([209.132.183.28]:44996) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1aGS5j-0006DF-5y for qemu-devel@nongnu.org; Tue, 05 Jan 2016 08:56:03 -0500 References: <6ca84848.f052.15211b20317.Coremail.magazine.lihuiba@163.com> From: Eric Blake Message-ID: <568BCB6C.7010709@redhat.com> Date: Tue, 5 Jan 2016 06:55:56 -0700 MIME-Version: 1.0 In-Reply-To: <6ca84848.f052.15211b20317.Coremail.magazine.lihuiba@163.com> Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="1p44SaeJ1G2rgREIhskQ2uodbXPmta0Kp" Subject: Re: [Qemu-devel] qcow2 snapshot + resize List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: lihuiba , "qemu-devel@nongnu.org" This is an OpenPGP/MIME signed message (RFC 4880 and 3156) --1p44SaeJ1G2rgREIhskQ2uodbXPmta0Kp Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable On 01/05/2016 05:10 AM, lihuiba wrote: >>> In our production environment, we need to extend a qcow2 image with >>> snapshots in it. >> The thing is that one would need to update all the inactive L1 tables.= I >> don't think it should be too difficult, it's just that apparently so f= ar >> nobody ever had the need for this feature. Is resizing a snapshot really what you want? Ideally, a snapshot tracks the data from a point in time, including the metadata of the size being tracked at that time. Extending the snapshots then reverting to that snapshot means your guest would see a larger disk on revert than it did at the time the snapshot was created, which guests might not handle very well. --=20 Eric Blake eblake redhat com +1-919-301-3266 Libvirt virtualization library http://libvirt.org --1p44SaeJ1G2rgREIhskQ2uodbXPmta0Kp Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v2 Comment: Public key at http://people.redhat.com/eblake/eblake.gpg Comment: Using GnuPG with Thunderbird - http://www.enigmail.net/ iQEcBAEBCAAGBQJWi8tsAAoJEKeha0olJ0NqxkcH/3Gm1Yoiy1OL5qyfvf0XQ2jw YAzELH+wOgot0RSEHIDq3C0hNEAjBdn/ZU8hpXgdsOKfmQBVFJ0gVPj094QUG54x dDCTsTvg481e8J+K3xW4dVjHGLJyZxm6YjASj6W4RgyMFZTFPGvtAIsPcR8Sibqw 9v9axlCgc69auZaQ010QLnGiwpjwPRSIg3tHtZNKfIhJ/7XcFdQT3FBMc30IF2wk Ba/LpBbmxu4Q/h7s7CBTuAP3Yr4d7WOZYgjPf9W6IDpKNF+EMA/jrqa6cPqUnHPI /CouekcCBS0NcTYNgKiyutg/XTndo9j8BjX6UaI947mA0Q6dbYdnwfDGF5d3cGQ= =DbkP -----END PGP SIGNATURE----- --1p44SaeJ1G2rgREIhskQ2uodbXPmta0Kp--