From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-1.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id C17F2C0044C for ; Tue, 6 Nov 2018 02:45:22 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 82EB02083D for ; Tue, 6 Nov 2018 02:45:22 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 82EB02083D Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729536AbeKFMIN (ORCPT ); Tue, 6 Nov 2018 07:08:13 -0500 Received: from mx1.redhat.com ([209.132.183.28]:38140 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726389AbeKFMIM (ORCPT ); Tue, 6 Nov 2018 07:08:12 -0500 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.phx2.redhat.com [10.5.11.23]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id C7070308FB90; Tue, 6 Nov 2018 02:45:19 +0000 (UTC) Received: from [10.72.12.184] (ovpn-12-184.pek2.redhat.com [10.72.12.184]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 761B71948B; Tue, 6 Nov 2018 02:45:10 +0000 (UTC) Subject: Re: [PATCH 0/1] vhost: add vhost_blk driver To: Vitaly Mayatskih Cc: "Michael S . Tsirkin" , Paolo Bonzini , kvm@vger.kernel.org, virtualization@lists.linux-foundation.org, linux-kernel@vger.kernel.org, stefanha@redhat.com References: <20181102182123.29420-1-v.mayatskih@gmail.com> <6a7f1668-bf2d-0caa-2efd-c8fab5f1db24@redhat.com> From: Jason Wang Message-ID: <57eefa62-7e66-786d-441c-5dd6b0d451a5@redhat.com> Date: Tue, 6 Nov 2018 10:45:08 +0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.2.1 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit Content-Language: en-US X-Scanned-By: MIMEDefang 2.84 on 10.5.11.23 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.43]); Tue, 06 Nov 2018 02:45:19 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2018/11/5 上午11:23, Vitaly Mayatskih wrote: > On Sun, Nov 4, 2018 at 10:00 PM Jason Wang wrote: > >>> # fio num-jobs >>> # A: bare metal over block >>> # B: bare metal over file >>> # C: virtio-blk over block >>> # D: virtio-blk over file >>> # E: vhost-blk bio over block >>> # F: vhost-blk kiocb over block >>> # G: vhost-blk kiocb over file >>> # >>> # A B C D E F G >>> 16 1480k 1506k 101k 102k 1346k 1202k 566k >> Hi: >> >> Thanks for the patches. >> >> This is not the first attempt for having vhost-blk: >> >> - Badari's version: https://lwn.net/Articles/379864/ >> >> - Asias' version: https://lwn.net/Articles/519880/ >> >> It's better to describe the differences (kiocb vs bio? performance?). >> E.g if my memory is correct, Asias said it doesn't give much improvement >> compared with userspace qemu. >> >> And what's more important, I believe we tend to use virtio-scsi nowdays. >> So what's the advantages of vhost-blk over vhost-scsi? > Hi, > > Yes, I saw both. Frankly, my implementation is not that different, > because the whole thing has only twice more LOC that vhost/test.c. > > I posted my numbers (see in quoted text above the 16 queues case), > IOPS goes from ~100k to 1.2M and almost reaches the physical > limitation of the backend. > > submit_bio() is a bit faster, but can't be used for disk images placed > on a file system. I have that submit_bio implementation too. > > Storage industry is shifting away from SCSI, which has a scaling > problem. Know little about storage. For scaling, do you mean SCSI protocol itself? If not, it's probably not a real issue for virtio-scsi itself. > I can compare vhost-scsi vs vhost-blk if you are curious. It would be very helpful to see the performance comparison. Thanks > Thanks!