From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mga01.intel.com (mga01.intel.com [192.55.52.88]) by dpdk.org (Postfix) with ESMTP id D29DE5942 for ; Wed, 27 Aug 2014 07:52:33 +0200 (CEST) Received: from fmsmga003.fm.intel.com ([10.253.24.29]) by fmsmga101.fm.intel.com with ESMTP; 26 Aug 2014 22:56:35 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.97,862,1389772800"; d="scan'208";a="377488007" Received: from fmsmsx103.amr.corp.intel.com ([10.19.9.34]) by FMSMGA003.fm.intel.com with ESMTP; 26 Aug 2014 22:52:24 -0700 Received: from fmsmsx114.amr.corp.intel.com (10.18.116.8) by FMSMSX103.amr.corp.intel.com (10.19.9.34) with Microsoft SMTP Server (TLS) id 14.3.195.1; Tue, 26 Aug 2014 22:56:35 -0700 Received: from shsmsx104.ccr.corp.intel.com (10.239.4.70) by FMSMSX114.amr.corp.intel.com (10.18.116.8) with Microsoft SMTP Server (TLS) id 14.3.195.1; Tue, 26 Aug 2014 22:56:34 -0700 Received: from shsmsx101.ccr.corp.intel.com ([169.254.1.198]) by SHSMSX104.ccr.corp.intel.com ([169.254.5.17]) with mapi id 14.03.0195.001; Wed, 27 Aug 2014 13:56:32 +0800 From: "Xie, Huawei" To: Tetsuya.Mukawa , "Ouyang, Changchun" , "dev@dpdk.org" Thread-Topic: [dpdk-dev] [RFC] lib/librte_vhost: qemu vhost-user support into DPDK vhost library Thread-Index: Ac/BHV0IrPGOjNirTxKCPui4m3t8YwAAB/VwACaOCB8AANWTwA== Date: Wed, 27 Aug 2014 05:56:31 +0000 Message-ID: References: <53FD60FD.5090903@igel.co.jp> <53FD6C4E.5040907@igel.co.jp> In-Reply-To: <53FD6C4E.5040907@igel.co.jp> Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-originating-ip: [10.239.127.40] Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Cc: Katsuya MATSUBARA , "nakajima.yoshihiro@lab.ntt.co.jp" , Hitoshi Masutani Subject: Re: [dpdk-dev] [RFC] lib/librte_vhost: qemu vhost-user support into DPDK vhost library X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: patches and discussions about DPDK List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 27 Aug 2014 05:52:34 -0000 > -----Original Message----- > From: Tetsuya.Mukawa [mailto:mukawa@igel.co.jp] > Sent: Wednesday, August 27, 2014 1:28 PM > To: Ouyang, Changchun; dev@dpdk.org > Cc: Xie, Huawei; Katsuya MATSUBARA; nakajima.yoshihiro@lab.ntt.co.jp; > Hitoshi Masutani > Subject: Re: [dpdk-dev] [RFC] lib/librte_vhost: qemu vhost-user support i= nto > DPDK vhost library >=20 > Hi Changchun, >=20 > (2014/08/27 14:01), Ouyang, Changchun wrote: > > Agree with you, the performance should be same as the data path (RX/TX)= is > not affected, > > The difference between implementation only exists in the virtio device > creation and destroy stage. > Yes, I agree. Also There may be the difference, if a virtio-net driver > on a guest isn't poll mode like a virtio-net device driver in the > kernel. In the case, existing vhost implementation uses the eventfd > kernel module, and vhost-user implementation uses eventfd to kick the > driver. So I guess there will be the difference. For virtio-net device driver, there is still no difference. Existing soluti= on creates an eventfd module to install a fd in DPDK process pointing to th= e eventfd in qemu process. In vhost-user, the UNIX domain socket will do th= at work, create a new fd, install it in target DPDK server process, and mak= e it point to the eventfd in qemu process. >=20 > Anyway, about device creation and destruction, the difference will come > from transmission speed between unix domain socket and CUSE. I am not > sure which is faster. >=20 > Thanks, > Tetsuya >=20 >=20 > > > > Regards, > > Changchun > > > >> -----Original Message----- > >> From: Tetsuya.Mukawa [mailto:mukawa@igel.co.jp] > >> Sent: Wednesday, August 27, 2014 12:39 PM > >> To: Ouyang, Changchun; dev@dpdk.org > >> Cc: Xie, Huawei; Katsuya MATSUBARA; nakajima.yoshihiro@lab.ntt.co.jp; > >> Hitoshi Masutani > >> Subject: Re: [dpdk-dev] [RFC] lib/librte_vhost: qemu vhost-user suppor= t into > >> DPDK vhost library > >> > >> > >> (2014/08/27 9:43), Ouyang, Changchun wrote: > >>> Do we have performance comparison between both implementation? > >> Hi Changchun, > >> > >> If DPDK applications are running on both guest and host side, the > >> performance should be almost same, because while transmitting data vir= t > >> queues are accessed by virtio-net PMD and libvhost. In libvhost, the e= xisting > >> vhost implementation and a vhost-user implementation will shares or us= es > >> same code to access virt queues. So I guess the performance will be al= most > >> same. > >> > >> Thanks, > >> Tetsuya > >> > >> > >>> Thanks > >>> Changchun > >>> > >>> > >>> -----Original Message----- > >>> From: dev [mailto:dev-bounces@dpdk.org] On Behalf Of Xie, Huawei > >>> Sent: Tuesday, August 26, 2014 7:06 PM > >>> To: dev@dpdk.org > >>> Subject: Re: [dpdk-dev] [RFC] lib/librte_vhost: qemu vhost-user > >>> support into DPDK vhost library > >>> > >>> Hi all: > >>> We are implementing qemu official vhost-user interface into DPDK vhos= t > >> library, so there would be two coexisting implementations for user spa= ce > >> vhost backend. > >>> Pro and cons in my mind: > >>> Existing solution: > >>> Pros: works with qemu version before 2.1; Cons: depends on eventfd > >> proxy kernel module and extra maintenance effort Qemu vhost-user: > >>> Pros: qemu official us-vhost interface; Cons: onl= y available after > >> qemu 2.1 > >>> BR. > >>> huawei