From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mga06.intel.com (mga06.intel.com [134.134.136.31]) by dpdk.org (Postfix) with ESMTP id 32A301C00 for ; Wed, 10 May 2017 11:58:27 +0200 (CEST) Received: from fmsmga004.fm.intel.com ([10.253.24.48]) by orsmga104.jf.intel.com with ESMTP; 10 May 2017 02:58:26 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.38,318,1491289200"; d="scan'208";a="259373713" Received: from irsmsx152.ger.corp.intel.com ([163.33.192.66]) by fmsmga004.fm.intel.com with ESMTP; 10 May 2017 02:58:25 -0700 Received: from irsmsx156.ger.corp.intel.com (10.108.20.68) by IRSMSX152.ger.corp.intel.com (163.33.192.66) with Microsoft SMTP Server (TLS) id 14.3.319.2; Wed, 10 May 2017 10:58:25 +0100 Received: from irsmsx103.ger.corp.intel.com ([169.254.3.241]) by IRSMSX156.ger.corp.intel.com ([169.254.3.246]) with mapi id 14.03.0319.002; Wed, 10 May 2017 10:58:25 +0100 From: "Mcnamara, John" To: "Yang, Zhiyong" , "dev@dpdk.org" CC: "yuanhan.liu@linux.intel.com" , "maxime.coquelin@redhat.com" Thread-Topic: [PATCH] doc: update virtio doc Thread-Index: AQHSyVX7Pp1LBdL2V0WoX/un9NIl96HtT7kA Date: Wed, 10 May 2017 09:58:24 +0000 Message-ID: References: <1494397104-56154-1-git-send-email-zhiyong.yang@intel.com> In-Reply-To: <1494397104-56154-1-git-send-email-zhiyong.yang@intel.com> Accept-Language: en-GB, en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-ctpclassification: CTP_PUBLIC x-titus-metadata-40: eyJDYXRlZ29yeUxhYmVscyI6IiIsIk1ldGFkYXRhIjp7Im5zIjoiaHR0cDpcL1wvd3d3LnRpdHVzLmNvbVwvbnNcL0ludGVsMyIsImlkIjoiYmVjZjkzNmYtZTczMC00NWRhLTlhMTAtZDMzODM4ZGFhYjQ5IiwicHJvcHMiOlt7Im4iOiJDVFBDbGFzc2lmaWNhdGlvbiIsInZhbHMiOlt7InZhbHVlIjoiQ1RQX1BVQkxJQyJ9XX1dfSwiU3ViamVjdExhYmVscyI6W10sIlRNQ1ZlcnNpb24iOiIxNS45LjYuNiIsIlRydXN0ZWRMYWJlbEhhc2giOiJIeGJiS2ZBaEFKeHhWQ1Mwcnh4d1cyMGtraTMwMW1uSm5DV05xYmhZSTRrPSJ9 dlp-product: dlpe-windows dlp-version: 10.0.102.7 dlp-reaction: no-action x-originating-ip: [163.33.239.181] Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Subject: Re: [dpdk-dev] [PATCH] doc: update virtio doc X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 10 May 2017 09:58:28 -0000 > -----Original Message----- > From: Yang, Zhiyong > Sent: Wednesday, May 10, 2017 7:18 AM > To: dev@dpdk.org; Mcnamara, John > Cc: yuanhan.liu@linux.intel.com; maxime.coquelin@redhat.com; Yang, Zhiyon= g > > Subject: [PATCH] doc: update virtio doc >=20 > Add more explanations about vring size changes and virtio_header size. >=20 > Signed-off-by: Zhiyong Yang > --- > doc/guides/nics/virtio.rst | 13 +++++++++---- > 1 file changed, 9 insertions(+), 4 deletions(-) >=20 > diff --git a/doc/guides/nics/virtio.rst b/doc/guides/nics/virtio.rst inde= x > 91bedea..36ddd08 100644 > --- a/doc/guides/nics/virtio.rst > +++ b/doc/guides/nics/virtio.rst > @@ -41,8 +41,8 @@ The DPDK extends kni to support vhost raw socket > interface, which enables vhost to directly read/ write packets from/to a > physical port. > With this enhancement, virtio could achieve quite promising performance. >=20 > -In future release, we will also make enhancement to vhost backend, - > releasing peak performance of virtio PMD driver. > +In future release, we will also make enhancement to vhost backend. > +Peak performance of virtio PMD driver will be released with every releas= e > version since DPDK 17.02 release. Hi, There have been great performance improvements in Virtio in the last few releases. However, we can't really promise that is will improve in every release. I'd suggest removing these two lines and the previous line starting with "With this enhancement, virtio could ...". >=20 > ... >=20 > -* RTE_PKTMBUF_HEADROOM should be defined larger than sizeof(struct > virtio_net_hdr), which is 10 bytes. > +* RTE_PKTMBUF_HEADROOM should be defined > + larger than sizeof(struct virtio_net_hdr), which is 10 bytes, when > using non-mergeable. > + larger than sizeof(struct virtio_net_hdr_mrg_rxbuf), which is 12 > bytes when mergeable or F_VERSION_1 > + is set. >=20 All constants and struct names should be ```` quoted. Like this: * ``RTE_PKTMBUF_HEADROOM`` should be defined larger than ``sizeof(struct virtio_net_hdr)``, which is 10 bytes, when using non-mergeable or larger than ``sizeof(struct virtio_net_hdr_mrg_rxbuf)`= `, which is 12 bytes when mergeable or ``F_VERSION_1`` is set. John