From mboxrd@z Thu Jan 1 00:00:00 1970 From: Thomas Monjalon Subject: Re: [PATCH 0/3] virtio_user as an alternative exception path Date: Fri, 02 Dec 2016 15:44:26 +0100 Message-ID: <1690999.5JB2ccKKLB@xps13> References: <1480689075-66977-1-git-send-email-jianfeng.tan@intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7Bit Cc: dev@dpdk.org, yuanhan.liu@linux.intel.com, ferruh.yigit@intel.com, cunming.liang@intel.com To: Jianfeng Tan Return-path: Received: from mail-wm0-f45.google.com (mail-wm0-f45.google.com [74.125.82.45]) by dpdk.org (Postfix) with ESMTP id 2900258C8 for ; Fri, 2 Dec 2016 15:44:28 +0100 (CET) Received: by mail-wm0-f45.google.com with SMTP id a197so18962256wmd.0 for ; Fri, 02 Dec 2016 06:44:28 -0800 (PST) In-Reply-To: <1480689075-66977-1-git-send-email-jianfeng.tan@intel.com> List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org Sender: "dev" 2016-12-02 14:31, Jianfeng Tan: > In v16.07, we upstreamed a virtual device, virtio_user (with vhost-user > as the backend). The path to go with a vhost-kernel backend has been > dropped for bad performance comparing to vhost-user and code simplicity. > > But after a second thought, virtio_user + vhost-kernel is a good > candidate as an exceptional path, such as KNI, which exchanges packets > with kernel networking stack. > - maintenance: vhost-net (kernel) is upstreamed and extensively used > kernel module. We don't need any out-of-tree module like KNI. > - performance: as with KNI, this solution would use one or more > kthreads to send/receive packets from user space DPDK applications, > which has little impact on user space polling thread (except that > it might enter into kernel space to wake up those kthreads if > necessary. > - features: vhost-net is born to be a networking solution, which has > lots of networking related featuers, like multi queue, tso, multi-seg > mbuf, etc. That's a really interesting trial. Have I already said that I don't like KNI? ;) > Known issues for current version: > - Multiqueue not supported yet. > - Offloading is completely enabled yet; to enhance, we will translate Is a "not" missing in this sentence? > the virtio header info into mbuf metadata when receiving packets > from kernel; and translate mbuf metadata info into virtio header > when sending packets to kernel. So what is the ambition for 17.02? Do you think it could be integrated?