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 571E7ECAAD1 for ; Wed, 31 Aug 2022 19:49:58 +0000 (UTC) Received: from localhost ([::1]:34864 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1oTTin-0007sC-4m for qemu-devel@archiver.kernel.org; Wed, 31 Aug 2022 15:49:57 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:33098) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1oTTdN-0002gT-8N for qemu-devel@nongnu.org; Wed, 31 Aug 2022 15:44:21 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]:25915) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1oTTdL-0007MT-Qb for qemu-devel@nongnu.org; Wed, 31 Aug 2022 15:44:20 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1661975057; 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=Oj1Vxtv9cqNzOiPgqoepi9Mws/jh6WtyWlv1vHcT27E=; b=gxKkT7Hkdwq5+7Wg3N1uTcY3DettztGpHZhFcgNLrcExL9aUpJbue/1Rk6bWyKLE8+6HMr 8308SZ///IUBjjbsGp2equ86b1IwIA0mALodR5cNHFV6QDI9CmOn2NMP4kgXFPJqMzajVz 1LFNvCh5q42C8RdWDaa2EyHThtkbKEg= 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-520-PVhTh7czNkmdRMSwnvoB2Q-1; Wed, 31 Aug 2022 15:44:14 -0400 X-MC-Unique: PVhTh7czNkmdRMSwnvoB2Q-1 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.rdu2.redhat.com [10.11.54.3]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 7421A294EDDD; Wed, 31 Aug 2022 19:44:13 +0000 (UTC) Received: from localhost (unknown [10.39.192.75]) by smtp.corp.redhat.com (Postfix) with ESMTP id B8A78112131E; Wed, 31 Aug 2022 19:44:12 +0000 (UTC) Date: Wed, 31 Aug 2022 15:44:10 -0400 From: Stefan Hajnoczi To: Vladimir Sementsov-Ogievskiy Cc: qemu-devel@nongnu.org, Paolo Bonzini , "Denis V. Lunev" , Peter Xu , Yanan Wang , Marcel Apfelbaum , "Richard W.M. Jones" , qemu-block@nongnu.org, John Snow , integration@gluster.org, Vladimir Sementsov-Ogievskiy , David Hildenbrand , Laurent Vivier , Markus Armbruster , Raphael Norwitz , Richard Henderson , Fam Zheng , sgarzare@redhat.com, Alberto Faria , Kevin Wolf , Wen Congyang , Eric Blake , Hanna Reitz , Philippe =?iso-8859-1?Q?Mathieu-Daud=E9?= , Eduardo Habkost , "Michael S. Tsirkin" , Thomas Huth , Jeff Cody , Xie Changlong Subject: Re: [RFC v4 00/11] blkio: add libblkio BlockDriver Message-ID: References: <20220822222402.176088-1-stefanha@redhat.com> <15ad1a46-00e5-ccc8-1c7e-f6061bc68c0c@yandex-team.ru> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="661EKS1Y5rttSm9r" Content-Disposition: inline In-Reply-To: <15ad1a46-00e5-ccc8-1c7e-f6061bc68c0c@yandex-team.ru> X-Scanned-By: MIMEDefang 2.78 on 10.11.54.3 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, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=unavailable 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" --661EKS1Y5rttSm9r Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Tue, Aug 23, 2022 at 08:31:03PM +0300, Vladimir Sementsov-Ogievskiy wrot= e: > On 8/23/22 01:23, Stefan Hajnoczi wrote: > > The remainder of the patch series reworks the existing QEMU bdrv_regist= er_buf() > > API so virtio-blk emulation efficiently map guest RAM for libblkio - so= me > > libblkio drivers require that I/O buffer memory is pre-registered (thin= k VFIO, > > vhost, etc). >=20 > Hi! >=20 > So patches 01-11 are for performance optimization? Don't you have some pe= rformance measurements for it? Hi Vladimir, I ran the patches against qemu-storage-daemon's vhost-user-blk export with iodepth=3D1 bs=3D512 to see the per-request overhead due to bounce buffer allocation/mapping: Name IOPS Error bounce-buf 4373.81 =B1 0.01% registered-buf 13062.80 =B1 0.67% The BDRV_REQ_REGISTERED_BUF optimization version is about 3x faster. Note that IOPS is low because the vhost-user-blk vq is not passed through to the guest yet (Stefano is working on this). The guest is also using interrupts, not polling (recent Linux virtio_blk.ko drivers support poll queues). I'll also include performance results in the next revision of the patch series. Stefan --661EKS1Y5rttSm9r Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQEzBAEBCAAdFiEEhpWov9P5fNqsNXdanKSrs4Grc8gFAmMPugkACgkQnKSrs4Gr c8gWQggAsA7NmhLqrCPbfHLhKb2rnSP0ywEDn2Cy/PqjFDeG2DZRvItq/NA4v1AD Wso40BZx6Khiw3Y7zxViLvcY6WukZQw+6gDlnO6Hbz0oi3tYAcPCRnKM3YRlI1WH uW7cGnlvwK6XPOFhIc+46fYhXztMBIWDiDRi30x16clyEBXBBcW2aQ3xt8pMdhdd A8Vtxmaef1UKGgr18FHgqF7YpB4EuUDzw2diogHtWTWlOlJbC1/IizJqnhUBlbO7 ym3oUkSIaB6Vk+n3nQclHXm9dF1S7e+iHHMe5ZFHnbIzqOQxnkgPys8kauk87vIG lruRfiZ8af4hNnh1ryOSNbZwr/LUww== =tnOX -----END PGP SIGNATURE----- --661EKS1Y5rttSm9r--