From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:40968) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1YJ1tj-000183-Hk for qemu-devel@nongnu.org; Wed, 04 Feb 2015 10:29:48 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1YJ1tg-0007aD-DF for qemu-devel@nongnu.org; Wed, 04 Feb 2015 10:29:47 -0500 Received: from mx1.redhat.com ([209.132.183.28]:36707) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1YJ1mh-0004iu-Bl for qemu-devel@nongnu.org; Wed, 04 Feb 2015 10:22:31 -0500 Received: from int-mx11.intmail.prod.int.phx2.redhat.com (int-mx11.intmail.prod.int.phx2.redhat.com [10.5.11.24]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id t14FMUkS018707 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=FAIL) for ; Wed, 4 Feb 2015 10:22:30 -0500 Message-ID: <54D23932.8060101@redhat.com> Date: Wed, 04 Feb 2015 16:22:26 +0100 From: Paolo Bonzini MIME-Version: 1.0 References: <20150204113229.GN3032@redhat.com> <54D213E0.8090408@redhat.com> <20150204130041.GQ3032@redhat.com> <54D221BC.50008@redhat.com> <20150204140820.GS3032@redhat.com> <54D22B5A.5020904@redhat.com> <20150204143452.GV3032@redhat.com> <54D23501.5020200@redhat.com> <20150204151105.GY3032@redhat.com> In-Reply-To: <20150204151105.GY3032@redhat.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] RFC: Universal encryption on QEMU I/O channels List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: "Daniel P. Berrange" Cc: qemu-devel@nongnu.org On 04/02/2015 16:11, Daniel P. Berrange wrote: > > For GIO/GIOChannel, you'd have to choose between zerocopy and many > > syscalls, or one copy and few syscalls. Since every page has two iov > > entries, one of which is just 8 bytes, one copy and few syscalls is > > probably faster---but still only half the speed of writev. > > That could be an argument in favour of defining a QEMUIOChannel > instead. The use of GIOChannel is only compelling if we gain some > significant benefit from using the standard glib API in this scenario > and I'm not clear that we really do, other than developer familiarity > with glib. GIOChannel's advantage is that---even though it may not be used for regular migration---integration with chardev would be really easy. > GIO could be compelling if we could leverage its TLS integration I agree. Paolo