From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753373Ab1HAIM1 (ORCPT ); Mon, 1 Aug 2011 04:12:27 -0400 Received: from 173-166-109-252-newengland.hfc.comcastbusiness.net ([173.166.109.252]:33144 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752708Ab1HAIMI (ORCPT ); Mon, 1 Aug 2011 04:12:08 -0400 Date: Mon, 1 Aug 2011 04:12:01 -0400 From: Christoph Hellwig To: Liu Yuan Cc: Badari Pulavarty , Stefan Hajnoczi , "Michael S. Tsirkin" , Rusty Russell , Avi Kivity , kvm@vger.kernel.org, linux-kernel@vger.kernel.org, Khoa Huynh Subject: Re: [RFC PATCH]vhost-blk: In-kernel accelerator for virtio block device Message-ID: <20110801081201.GA26472@infradead.org> References: <1311863346-4338-1-git-send-email-namei.unix@gmail.com> <4E325F98.5090308@gmail.com> <4E32F7F2.4080607@us.ibm.com> <4E363DB9.70801@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4E363DB9.70801@gmail.com> User-Agent: Mutt/1.5.21 (2010-09-15) X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org See http://www.infradead.org/rpr.html Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Aug 01, 2011 at 01:46:33PM +0800, Liu Yuan wrote: > >- I focused on using vfs interfaces in the kernel, so that I can > >use it for file-backed devices. > >Our use-case scenario is mostly file-backed images. > > > vhost-blk's that uses Linux AIO also support file-backed images. > Actually, I have run Guests both on raw partition and raw file > images. Note tjat it will only perform very well for preallocated images (just like aio=native in qemu) - if you use sparse images it will have to call into the allocator, which blocks for metadata I/O even in aio mode.