From mboxrd@z Thu Jan 1 00:00:00 1970 From: Yerden Zhumabekov Subject: Re: random pkt generator PMD Date: Thu, 16 Jun 2016 12:20:04 +0600 Message-ID: <57624514.5020004@sts.kz> References: <5761235C.2090906@sts.kz> <20160615130231.GB20120@hmsreliant.think-freely.org> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Cc: dev@dpdk.org To: Neil Horman Return-path: Received: from mgw.gov.kz (mgw.gov.kz [89.218.88.242]) by dpdk.org (Postfix) with ESMTP id 05B5EC534 for ; Thu, 16 Jun 2016 08:20:06 +0200 (CEST) In-Reply-To: <20160615130231.GB20120@hmsreliant.think-freely.org> List-Id: patches and discussions about DPDK List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org Sender: "dev" On 15.06.2016 19:02, Neil Horman wrote: > On Wed, Jun 15, 2016 at 03:43:56PM +0600, Yerden Zhumabekov wrote: >> Hello everybody, >> >> DPDK already got a number of PMDs for various eth devices, it even has PMD >> emulations for backends such as pcap, sw rings etc. >> >> I've been thinking about the idea of having PMD which would generate mbufs >> on the fly in some randomized fashion. This would serve goals like, for >> example: >> >> 1) running tests for applications with network processing capabilities >> without additional software packet generators; >> 2) making performance measurements with no hw inteference; >> 3) ability to run without root privileges, --no-pci, --no-huge, for CI >> build, so on. >> >> Maybe there's no such need, and these goals may be achieved by other means >> and this idea is flawed? Any thoughts? >> > I think you already have a solution to this problem. Linux/BSD have multiple > user space packet generators that can dump thier output to a pcap format file, > and dpdk has a pcap pmd that accepts a pcap file as input to send in packets. Things that I don't like about the idea of using PCAP PMD: 1) the need to create additional files with additional scripts and keep those with your test suite; 2) the need to rewind pcap once you played it (fixable); 3) reading packets one-by-one, file operations which may lead to perf impact; 4) low variability among source packets. Those are things which put me on idea of randomized packet generator PMD. Possible devargs could be: 1) id of a template, like "ipv4", "ipv6", "dot1q" etc; 2) size of mbuf payload; 3) array of tuples like (offset, size, value) with value being exact value or "rnd" keyword.