From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:38906) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1eEhvf-0001KB-De for qemu-devel@nongnu.org; Tue, 14 Nov 2017 15:35:33 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1eEhve-0006IJ-CS for qemu-devel@nongnu.org; Tue, 14 Nov 2017 15:35:31 -0500 References: <94700229-5afe-159f-9453-f507b9c83085@redhat.com> <0c42f84d-9096-3f7b-c71d-664a119bc8a2@redhat.com> <9ab7ae12-730d-a4d4-287c-64dcd509b680@redhat.com> <1fa78bdf-65e2-c216-49a2-7277231a7141@redhat.com> <20253223-df8f-162d-b8c8-dfa56af9fffd@redhat.com> From: Max Reitz Message-ID: <89062bb7-f2fa-db5e-d799-c61e1daa6b99@redhat.com> Date: Tue, 14 Nov 2017 21:35:18 +0100 MIME-Version: 1.0 In-Reply-To: Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="cMR9u3SeDosC5OBJdJPuvPtLaC3MsRQCj" Subject: Re: [Qemu-devel] using "qemu-img convert -O qcow2" to convert qcow v1 to v2 creates a qcow v3 file? List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: John Snow , Thomas Huth , Eric Blake , Peter Maydell , QEMU Developers Cc: Kevin Wolf , Qemu-block This is an OpenPGP/MIME signed message (RFC 4880 and 3156) --cMR9u3SeDosC5OBJdJPuvPtLaC3MsRQCj From: Max Reitz To: John Snow , Thomas Huth , Eric Blake , Peter Maydell , QEMU Developers Cc: Kevin Wolf , Qemu-block Message-ID: <89062bb7-f2fa-db5e-d799-c61e1daa6b99@redhat.com> Subject: Re: [Qemu-devel] using "qemu-img convert -O qcow2" to convert qcow v1 to v2 creates a qcow v3 file? References: <94700229-5afe-159f-9453-f507b9c83085@redhat.com> <0c42f84d-9096-3f7b-c71d-664a119bc8a2@redhat.com> <9ab7ae12-730d-a4d4-287c-64dcd509b680@redhat.com> <1fa78bdf-65e2-c216-49a2-7277231a7141@redhat.com> <20253223-df8f-162d-b8c8-dfa56af9fffd@redhat.com> In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable On 2017-11-14 21:30, John Snow wrote: >=20 >=20 > On 11/14/2017 01:46 PM, Max Reitz wrote: >> On 2017-11-14 19:45, Thomas Huth wrote: >>> On 14.11.2017 14:32, Max Reitz wrote: >>> [...] >>>> Well, do you want to document it? I'd rather deprecate it altogethe= r. >>> >>> Maybe a first step could be to change qemu-img so that it refuses to >>> create new qcow1 images (but still can convert them into other format= s). >>> So basically make qcow1 read-only? >> >> Yep, and the actual first step to that is to make it issue a deprecati= on >> warning when creating qcow v1 images (which is what I proposed). :-) >> >> Max >> >=20 > Deprecation warning is good. >=20 > In future versions you can shimmy it behind a > --no-really-I-want-this-old-format option, I think we ought to support > creating the images for as long as is technologically convenient. Well, at some point you can also demand from users to just dig out some old version of qemu-img to convert their qcow v1 images to qcow2. It's not like they are going to miss out on anything. (If you deprecate emulated hardware, users may complain that they don't get the newest qemu features/bugfixes/... while continuing to use that hardware, so I can see that it's a tough decision whether to deprecate that. But it's not like you are going to lose any features or anything if you convert your dusty images to qcow2. On the contrary, we're helping you to get more performance out of them. Maybe qemu should just silently convert qcow v1 images to qcow2 without asking the user, like Apple did...) Max --cMR9u3SeDosC5OBJdJPuvPtLaC3MsRQCj Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- iQFGBAEBCAAwFiEEkb62CjDbPohX0Rgp9AfbAGHVz0AFAloLU4YSHG1yZWl0ekBy ZWRoYXQuY29tAAoJEPQH2wBh1c9A4DYIAMQj+RhpU2tC+mpc3b36UP0xG8YYucgK H8wQIDH/8IMe+nMhlBT0y2FwAN9Buv/8kOEB+q2/e6uCPjIKlAlK0FHVpdENEycM q4PZypm5abrpKBBtE3b0BXkhxqSB8Ukm181nNtto4I31cz3XFSA763S1AurDVYxR 7b6QIPY/AN4j7+yzvuh67RtGBm4nw5JLXtHtcE7DJvvUqxmqnI6+BtCM245FC1ot es8yzaS22kE0faj1RzTaH1jWR2G1CCFJ9fQ5VBM6Reqx8Kzf87Om+MnQnlJYoqvN cYnT19n1e2oxj9tdNwipnJyE0Rq/GqszbNREvpIyMa/1uB32wJQK6dM= =YMF5 -----END PGP SIGNATURE----- --cMR9u3SeDosC5OBJdJPuvPtLaC3MsRQCj--