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 Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 607FAC433F5 for ; Tue, 4 Oct 2022 20:15:24 +0000 (UTC) Received: from localhost ([::1]:35896 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1ofoK3-0001K9-FH for qemu-devel@archiver.kernel.org; Tue, 04 Oct 2022 16:15:23 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:36354) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1ofo6r-0004B2-St for qemu-devel@nongnu.org; Tue, 04 Oct 2022 16:01:46 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]:57234) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1ofo6o-00068L-7n for qemu-devel@nongnu.org; Tue, 04 Oct 2022 16:01:44 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1664913699; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=2fo73h3AwQsMc+EkPLrp4vxatJszk50vU8sLiifowgY=; b=BljQ9sgPW4Vwm7TB3y64TnOiC9C0mdnCb+ObwCQfC1Y+28VYmzB2KoRpAgwAtri8avPmwi 6WGZBGAih8n4QP7X3bUpJUltugXPwn3yaOCXdpSPnzjnOJGfC90t/uqzMHY8GatXNTOYlF ycuq1y08Cze9UnRNK43dDZJZ30iFyYY= Received: from mimecast-mx02.redhat.com (mx3-rdu2.redhat.com [66.187.233.73]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-282-grH5W0I7OHOm2dpV10ZCQg-1; Tue, 04 Oct 2022 16:01:36 -0400 X-MC-Unique: grH5W0I7OHOm2dpV10ZCQg-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.rdu2.redhat.com [10.11.54.6]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 0EC023C6EAA1; Tue, 4 Oct 2022 20:01:36 +0000 (UTC) Received: from localhost (unknown [10.39.192.79]) by smtp.corp.redhat.com (Postfix) with ESMTP id 7417B2166B26; Tue, 4 Oct 2022 20:01:35 +0000 (UTC) Date: Tue, 4 Oct 2022 14:13:52 -0400 From: Stefan Hajnoczi To: Andrey Zhadchenko Cc: qemu-block@nongnu.org, qemu-devel@nongnu.org, kwolf@redhat.com, hreitz@redhat.com, mst@redhat.com, den@virtuozzo.com Subject: Re: [RFC patch 0/1] block: vhost-blk backend Message-ID: References: <20220725205527.313973-1-andrey.zhadchenko@virtuozzo.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="sCIr0AXttG/ZprTh" Content-Disposition: inline In-Reply-To: <20220725205527.313973-1-andrey.zhadchenko@virtuozzo.com> X-Scanned-By: MIMEDefang 3.1 on 10.11.54.6 Received-SPF: pass client-ip=170.10.133.124; envelope-from=stefanha@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" --sCIr0AXttG/ZprTh Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Mon, Jul 25, 2022 at 11:55:26PM +0300, Andrey Zhadchenko wrote: > Although QEMU virtio-blk is quite fast, there is still some room for > improvements. Disk latency can be reduced if we handle virito-blk requests > in host kernel so we avoid a lot of syscalls and context switches. >=20 > The biggest disadvantage of this vhost-blk flavor is raw format. > Luckily Kirill Thai proposed device mapper driver for QCOW2 format to att= ach > files as block devices: https://www.spinics.net/lists/kernel/msg4292965.h= tml >=20 > Also by using kernel modules we can bypass iothread limitation and finaly= scale > block requests with cpus for high-performance devices. This is planned to= be > implemented in next version. Hi Andrey, Do you have a new version of this patch series that uses multiple threads? I have been playing with vq-IOThread mapping in QEMU and would like to benchmark vhost-blk vs QEMU virtio-blk mq IOThreads: https://gitlab.com/stefanha/qemu/-/tree/virtio-blk-mq-iothread-prototype Thanks, Stefan --sCIr0AXttG/ZprTh Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQEzBAEBCAAdFiEEhpWov9P5fNqsNXdanKSrs4Grc8gFAmM8d+AACgkQnKSrs4Gr c8gjEQgApuJzj3L7UofyFcA9yAxImpkhWHI46iuzmE4d81hreWHmxTQ/vh143xUc 9Vu6XonmoD9KVfDE0dWIoAmMsyHl00hDU1MHvu/jr/9Umv2v6JkEjBT7ETOol7dR HLCAZY9dtuptJEbqMb0t2pYDBFQnDXqGh0gKKnvMBdzuuBQCd62ZN0PEp86ohvZc QHOrQTo0dPbqa/gxhdwSEuFxFvXPhh1IV1oqRKu+He7N4Zi76f3EQZejJ/VFVYk+ hTby8AjGVyUdv1HB51+xPLdlIf70XK/PoVbJFHLIqb0GKfm3+0oHxUbdcC3gwn+h m/pWlUDGrgU042aHX5sWrpQI22NQmg== =GiBY -----END PGP SIGNATURE----- --sCIr0AXttG/ZprTh--