From mboxrd@z Thu Jan 1 00:00:00 1970 From: Gerd Hoffmann Subject: Re: [Qemu-devel] [RFC] Replace posix-aio with custom thread pool Date: Fri, 12 Dec 2008 21:35:42 +0100 Message-ID: <4942CB1E.70505@redhat.com> References: <49400F69.8080707@codemonkey.ws> <20081210190810.GG18814@random.random> <20081212142435.GL6809@random.random> <494276CD.6060904@codemonkey.ws> <20081212154418.GM6809@random.random> <49429629.20309@codemonkey.ws> <20081212170916.GO6809@random.random> <49429EA3.8070008@codemonkey.ws> <20081212175213.GP6809@random.random> <4942AAD6.1090408@codemonkey.ws> <20081212182634.GQ6809@random.random> <4942C5C1.9080107@redhat.com> <4942C6F7.2080609@codemonkey.ws> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Cc: Andrea Arcangeli , qemu-devel@nongnu.org, kvm-devel To: Anthony Liguori Return-path: Received: from mx2.redhat.com ([66.187.237.31]:57156 "EHLO mx2.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752789AbYLLUga (ORCPT ); Fri, 12 Dec 2008 15:36:30 -0500 In-Reply-To: <4942C6F7.2080609@codemonkey.ws> Sender: kvm-owner@vger.kernel.org List-ID: Anthony Liguori wrote: > I don't know about grant table references b/c that's really foreign > memory. But this is a good argument against the DMA as it stands, b/c > you may be handing foreign memory to bdrv_aio_readv/writev. > > A big reason for the map/unmap lock/unlock abstraction though would be > the qemu-dm map cache. I think you could use it to pretty reasonably > integrate the map cache which I know I've previously could never be done > :-) I see we fully agree here. /me mumbles something about funny mail crossings. Maybe we should use irc next time to save some typing ;) cheers, Gerd