From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([209.51.188.92]:46431) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1hMcf7-000272-Nz for qemu-devel@nongnu.org; Fri, 03 May 2019 14:11:58 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1hMcf6-0001sv-R2 for qemu-devel@nongnu.org; Fri, 03 May 2019 14:11:57 -0400 Received: from userp2120.oracle.com ([156.151.31.85]:36660) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1hMcf6-0001rP-HS for qemu-devel@nongnu.org; Fri, 03 May 2019 14:11:56 -0400 Date: Fri, 03 May 2019 11:11:50 -0700 From: Wei Li Message-ID: References: <60340EAF-4C85-4798-9999-34F1A37E2086@oracle.com> <898ef1d4-bfa2-9952-8ceb-f1282b85e29c@oracle.com> <20190416092042.GB32709@stefanha-x1.localdomain> <8E5AF770-69ED-4D44-8A25-B51344996D9E@oracle.com> <3F7E854A-3C1D-4204-8C35-893FC0614796@oracle.com> <20190423120453.GF32465@stefanha-x1.localdomain> <44520476-d6a8-2e3f-1602-388e2e1e874e@redhat.com> <20190429134048.GH7587@stefanha-x1.localdomain> <1A278B43-AA26-43B4-B6C2-17231E780BBE@oracle.com> <20190501163650.GF21155@stefanha-x1.localdomain> <1823F9C3-8092-4B75-87AA-A05325032F48@oracle.com> <428e3ee5-28b0-7895-8a17-9178354c9406@redhat.com> In-Reply-To: <428e3ee5-28b0-7895-8a17-9178354c9406@redhat.com> Mime-version: 1.0 Content-type: text/plain; charset="UTF-8" Content-transfer-encoding: quoted-printable Subject: Re: [Qemu-devel] Following up questions related to QEMU and I/O Thread List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Paolo Bonzini , Stefan Hajnoczi Cc: Stefan Hajnoczi , Dongli Zhang , qemu-devel@nongnu.org Hi Paolo, That will be great, I would like to hear more details about the design and = implementation once you get those ready.=20 Thanks a lot, Wei =EF=BB=BFOn 5/3/19, 11:05 AM, "Paolo Bonzini" wrote: On 03/05/19 10:21, Wei Li wrote: > Got it, thanks Stefan for your clarification! =20 Hi Wei, =20 Stefan and I should be posting a patch to add Linux SCSI driver batching, and an implementation for virtio-scsi. =20 Paolo =20 > Wei >=20 > =EF=BB=BFOn 5/1/19, 9:36 AM, "Stefan Hajnoczi" wrote: >=20 > On Mon, Apr 29, 2019 at 10:56:31AM -0700, Wei Li wrote: > >Does this mean the performance could be improved via adding Batc= h I/O submission support in Guest driver side which will be able to reduce t= he number of virtqueue kicks? > =20 > Yes, I think so. It's not obvious to me how a Linux SCSI driver = is > supposed to implement batching though. The .queuecommand API doe= sn't > seem to include information relevant to batching. > =20 > Stefan > =20 > =20 >=20 >=20 =20 =20 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=-0.7 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,MIME_QP_LONG_LINE,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 1C492C43219 for ; Fri, 3 May 2019 18:12:56 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id DE1602075C for ; Fri, 3 May 2019 18:12:55 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=oracle.com header.i=@oracle.com header.b="QwaJW0PD" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org DE1602075C Authentication-Results: mail.kernel.org; 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Fri, 3 May 2019 18:11:53 GMT Received: from userv0122.oracle.com (userv0122.oracle.com [156.151.31.75]) by userp3030.oracle.com with ESMTP id 2s7p8afk1v-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Fri, 03 May 2019 18:11:53 +0000 Received: from abhmp0022.oracle.com (abhmp0022.oracle.com [141.146.116.28]) by userv0122.oracle.com (8.14.4/8.14.4) with ESMTP id x43IBqcE004053; Fri, 3 May 2019 18:11:52 GMT Received: from [10.74.111.122] (/10.74.111.122) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Fri, 03 May 2019 11:11:52 -0700 User-Agent: Microsoft-MacOutlook/10.15.0.190115 Date: Fri, 03 May 2019 11:11:50 -0700 From: Wei Li To: Paolo Bonzini , Stefan Hajnoczi Message-ID: Thread-Topic: [Qemu-devel] Following up questions related to QEMU and I/O Thread References: <60340EAF-4C85-4798-9999-34F1A37E2086@oracle.com> <898ef1d4-bfa2-9952-8ceb-f1282b85e29c@oracle.com> <20190416092042.GB32709@stefanha-x1.localdomain> <8E5AF770-69ED-4D44-8A25-B51344996D9E@oracle.com> <3F7E854A-3C1D-4204-8C35-893FC0614796@oracle.com> <20190423120453.GF32465@stefanha-x1.localdomain> <44520476-d6a8-2e3f-1602-388e2e1e874e@redhat.com> <20190429134048.GH7587@stefanha-x1.localdomain> <1A278B43-AA26-43B4-B6C2-17231E780BBE@oracle.com> <20190501163650.GF21155@stefanha-x1.localdomain> <1823F9C3-8092-4B75-87AA-A05325032F48@oracle.com> <428e3ee5-28b0-7895-8a17-9178354c9406@redhat.com> In-Reply-To: <428e3ee5-28b0-7895-8a17-9178354c9406@redhat.com> Mime-version: 1.0 Content-type: text/plain; charset="UTF-8" Content-transfer-encoding: quoted-printable X-Proofpoint-Virus-Version: vendor=nai engine=5900 definitions=9245 signatures=668685 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 suspectscore=0 malwarescore=0 phishscore=0 bulkscore=0 spamscore=0 mlxscore=0 mlxlogscore=956 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1810050000 definitions=main-1905030118 X-Proofpoint-Virus-Version: vendor=nai engine=5900 definitions=9245 signatures=668685 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 priorityscore=1501 malwarescore=0 suspectscore=0 phishscore=0 bulkscore=0 spamscore=0 clxscore=1015 lowpriorityscore=0 mlxscore=0 impostorscore=0 mlxlogscore=991 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1810050000 definitions=main-1905030118 X-detected-operating-system: by eggs.gnu.org: GNU/Linux 3.x [generic] X-Received-From: 156.151.31.85 Subject: Re: [Qemu-devel] Following up questions related to QEMU and I/O Thread X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Dongli Zhang , qemu-devel@nongnu.org, Stefan Hajnoczi Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" Message-ID: <20190503181150.oz8XSQwHdq9riAvTf8zsWbEKbVGIgTSF0r6LrtI4iks@z> Hi Paolo, That will be great, I would like to hear more details about the design and = implementation once you get those ready.=20 Thanks a lot, Wei =EF=BB=BFOn 5/3/19, 11:05 AM, "Paolo Bonzini" wrote: On 03/05/19 10:21, Wei Li wrote: > Got it, thanks Stefan for your clarification! =20 Hi Wei, =20 Stefan and I should be posting a patch to add Linux SCSI driver batching, and an implementation for virtio-scsi. =20 Paolo =20 > Wei >=20 > =EF=BB=BFOn 5/1/19, 9:36 AM, "Stefan Hajnoczi" wrote: >=20 > On Mon, Apr 29, 2019 at 10:56:31AM -0700, Wei Li wrote: > >Does this mean the performance could be improved via adding Batc= h I/O submission support in Guest driver side which will be able to reduce t= he number of virtqueue kicks? > =20 > Yes, I think so. It's not obvious to me how a Linux SCSI driver = is > supposed to implement batching though. The .queuecommand API doe= sn't > seem to include information relevant to batching. > =20 > Stefan > =20 > =20 >=20 >=20 =20 =20