From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:40082) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1WTZ6d-0001M3-1J for qemu-devel@nongnu.org; Fri, 28 Mar 2014 11:54:11 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1WTZ6Y-0001vv-3I for qemu-devel@nongnu.org; Fri, 28 Mar 2014 11:54:06 -0400 Received: from mx1.redhat.com ([209.132.183.28]:43924) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1WTZ6X-0001vk-QB for qemu-devel@nongnu.org; Fri, 28 Mar 2014 11:54:02 -0400 Message-ID: <53359B12.3030008@redhat.com> Date: Fri, 28 Mar 2014 09:53:54 -0600 From: Eric Blake MIME-Version: 1.0 References: <1396017982-7390-1-git-send-email-pl@kamp.de> In-Reply-To: <1396017982-7390-1-git-send-email-pl@kamp.de> Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="99R4fS7lFCmvlqXW3edUOa4wpqqS6k4oW" Subject: Re: [Qemu-devel] [PATCHv2] block: optimize zero writes with bdrv_write_zeroes List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Peter Lieven , qemu-devel@nongnu.org Cc: kwolf@redhat.com, famz@redhat.com, armbru@redhat.com, mreitz@redhat.com, stefanha@redhat.com, pbonzini@redhat.com This is an OpenPGP/MIME signed message (RFC 4880 and 3156) --99R4fS7lFCmvlqXW3edUOa4wpqqS6k4oW Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable On 03/28/2014 08:46 AM, Peter Lieven wrote: > this patch tries to optimize zero write requests > by automatically using bdrv_write_zeroes if it is > supported by the format. >=20 > This significantly speeds up file system initialization and > should speed zero write test used to test backend storage > performance. >=20 >=20 > block.c | 39 +++++++++++++++++++++++++++++++++++++= +- > include/block/block_int.h | 12 ++++++++++++ > include/qemu-common.h | 1 + > qemu-options.hx | 6 ++++++ > util/iov.c | 21 +++++++++++++++++++++ > 5 files changed, 78 insertions(+), 1 deletion(-) >=20 Is there any QMP query- command that can expose the current setting of this value? Is this something worth making changeable during runtime? Is it something that can be requested per-disk at hotplug time? --=20 Eric Blake eblake redhat com +1-919-301-3266 Libvirt virtualization library http://libvirt.org --99R4fS7lFCmvlqXW3edUOa4wpqqS6k4oW Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 Comment: Public key at http://people.redhat.com/eblake/eblake.gpg Comment: Using GnuPG with Thunderbird - http://www.enigmail.net/ iQEcBAEBCAAGBQJTNZsSAAoJEKeha0olJ0Nq8l4IAINGKNEVsEEx0o6qEEbkXLJk oMQrgz1uPhxJ1/doyK8Ffqp+6UDCUDm7u7kdAQeNbAH5YF3NThhnbld1Djg83dSD GyhNPGrF639v8tlkq5WKmSTg/sJrCkb0EvJZNcvreVQBlySyVTO4D0mMh8HWrnrq AUQbE14AEwSJi9MPuEU5H+861PYqyQ53+DsiP1hjaU09g91lgmJD5Us+fCZSICup //MCqWWNcDjGj4S1KwbJYFSL9EMU3TUvGmPZD2f4gELDC0fHeO9PwZKG/he7OZ4D qGvLvvO9wxqmwuNAlf9BzqJ5xMoAA9pi0W1aTQwfjVUBo02MTVeL80U00lLEgzo= =c9NA -----END PGP SIGNATURE----- --99R4fS7lFCmvlqXW3edUOa4wpqqS6k4oW--