From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:52080) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1YJis2-0006KX-KM for qemu-devel@nongnu.org; Fri, 06 Feb 2015 08:22:55 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1YJis0-0005Z0-PP for qemu-devel@nongnu.org; Fri, 06 Feb 2015 08:22:54 -0500 Received: from mx1.redhat.com ([209.132.183.28]:36494) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1YJis0-0005Y3-Dz for qemu-devel@nongnu.org; Fri, 06 Feb 2015 08:22:52 -0500 Message-ID: <54D4C021.106@redhat.com> Date: Fri, 06 Feb 2015 06:22:41 -0700 From: Eric Blake MIME-Version: 1.0 References: <54CBF2B2.20703@kamp.de> <20150205140029.GF19277@stefanha-thinkpad.redhat.com> <54D37E3D.7060208@kamp.de> <20150206104248.GD28079@stefanha-thinkpad.redhat.com> <54D49B59.2060104@kamp.de> In-Reply-To: <54D49B59.2060104@kamp.de> Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="4Ffk4H2ctSaw25K2Q46hHNLQUEw5wnMew" Subject: Re: [Qemu-devel] value of VIRTQUEUE_MAX_SIZE List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Peter Lieven , Stefan Hajnoczi Cc: Kevin Wolf , "Michael S. Tsirkin" , Stefan Hajnoczi , ming.lei@canonical.com, "qemu-devel@nongnu.org" , Max Reitz This is an OpenPGP/MIME signed message (RFC 4880 and 3156) --4Ffk4H2ctSaw25K2Q46hHNLQUEw5wnMew Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable On 02/06/2015 03:45 AM, Peter Lieven wrote: >>> The idea was that IOV_MAX is the limit in case of at least virtio-blk= =2E The host >>> will not support more than IOV_MAX iovecs passed to a block request. >> Is there an issue in practice? >=20 > If there is no platform where IOV_MAX is less than 1024 then not. POSIX allows for a system with IOV_MAX as small as 16. But these days, systems we care about probably have a much larger value; alas, I don't know off-hand what actual systems use to say if 1024 is a common minimum.= --=20 Eric Blake eblake redhat com +1-919-301-3266 Libvirt virtualization library http://libvirt.org --4Ffk4H2ctSaw25K2Q46hHNLQUEw5wnMew 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/ iQEcBAEBCAAGBQJU1MAhAAoJEKeha0olJ0NqhEwH/iQfNsppc8CzC9aIV08EsDMw MMfh6BRQBOk5ASlaZGpxi94XX0/tJRji4Q5YJzl4Z/0DzmvhdmogX7VpsFeqWB5O h0z+BEDTnj5FVUYtXXQ8dkBGHzBoDeTwgrgwWVBgnykETxpnv2PPd3MjrNwlyXPV iKa1ff0UMUzclbDhoo+JQRKogkpHN7R9SYgSsPU1KbuMXBsTRddHNYHdZNHQuVwQ tPwbIxfN7ph3gjfB6YfbStaTa6+QYEjvd8abUq3+bHMzZIyLwp4+FKftVX0EQyjw kLfv2IsSTheIy6XPyzziP6EsFozeluSLdg5/ntNCzbrpFp9hdtIBEjxoWkzu+1o= =hw84 -----END PGP SIGNATURE----- --4Ffk4H2ctSaw25K2Q46hHNLQUEw5wnMew--