From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752048Ab2FRICE (ORCPT ); Mon, 18 Jun 2012 04:02:04 -0400 Received: from mx1.redhat.com ([209.132.183.28]:24201 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751261Ab2FRICC (ORCPT ); Mon, 18 Jun 2012 04:02:02 -0400 Message-ID: <4FDEE0CB.1030505@redhat.com> Date: Mon, 18 Jun 2012 16:03:23 +0800 From: Asias He User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:13.0) Gecko/20120605 Thunderbird/13.0 MIME-Version: 1.0 To: Rusty Russell CC: kvm@vger.kernel.org, linux-kernel@vger.kernel.org, virtualization@lists.linux-foundation.org, "Michael S. Tsirkin" , Christoph Hellwig , Minchan Kim Subject: Re: [PATCH 3/3] virtio-blk: Add bio-based IO path for virtio-blk References: <1340002390-3950-1-git-send-email-asias@redhat.com> <1340002390-3950-4-git-send-email-asias@redhat.com> <87hau9yse7.fsf@rustcorp.com.au> In-Reply-To: <87hau9yse7.fsf@rustcorp.com.au> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 06/18/2012 03:46 PM, Rusty Russell wrote: > On Mon, 18 Jun 2012 14:53:10 +0800, Asias He wrote: >> This patch introduces bio-based IO path for virtio-blk. > > Why make it optional? request-based IO path is useful for users who do not want to bypass the IO scheduler in guest kernel, e.g. users using spinning disk. For users using fast disk device, e.g. SSD device, they can use bio-based IO path. -- Asias