From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-ig0-f172.google.com (mail-ig0-f172.google.com [209.85.213.172]) by dpdk.org (Postfix) with ESMTP id D523A592E for ; Fri, 25 Jul 2014 16:19:55 +0200 (CEST) Received: by mail-ig0-f172.google.com with SMTP id h15so847205igd.17 for ; Fri, 25 Jul 2014 07:21:28 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:sender:in-reply-to:references:from:date:message-id :subject:to:cc:content-type; bh=Vea7IJ41a0wmk5hGQAa8C2IqQypSJJMNlvHCvC/nIew=; b=vOqZKLKslXQK96MJAV+NDFbTew027fZQA8vWy6DTB0DkmP7E8NWfX2F3zTiigcjIg9 yDB5A6Karoxa4bjL6PrZAA1JoOJbRBB8wpD2eVGiZCiiPjmOWfjpW81LdAtdp+bGP7wd krkheZVUA+psAOvNfD7ifkt5jpGV9gjHomr3HhsMwbkxjc8lGrW8Z0gwNYPeGSe4vsKb 2kS3hxQ0WP8QD2C+lBIvDE2JpOXjPZv/uIT2ErQSxG3fXNLCioyXN44v2uygXqYgST8i rkdGFBztrLI/pU58d8+dQGx+xWUp4X37xpHvdgDv/fmmPCUNosaVigZHTDGDqdol2GK8 cR+w== X-Received: by 10.50.143.65 with SMTP id sc1mr5967299igb.19.1406298087952; Fri, 25 Jul 2014 07:21:27 -0700 (PDT) MIME-Version: 1.0 Sender: kay21s@gmail.com Received: by 10.64.206.166 with HTTP; Fri, 25 Jul 2014 07:21:07 -0700 (PDT) In-Reply-To: References: From: Kai Zhang Date: Fri, 25 Jul 2014 10:21:07 -0400 X-Google-Sender-Auth: galSNwCmFyMNjnlhhnBZYRvch2g Message-ID: To: "Wodkowski, PawelX" , alex@weka.io Content-Type: text/plain; charset=UTF-8 X-Content-Filtered-By: Mailman/MimeDel 2.1.15 Cc: "dev@dpdk.org" Subject: Re: [dpdk-dev] About round trip latency with DPDK 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: Fri, 25 Jul 2014 14:19:56 -0000 Thanks! I have found the problem. It is that I used clock_gettime() to measure the latency. With rte_rdtsc(), the round trip latency is measured to be less than 10 microseconds. Thanks very much, Kai On Thu, Jul 24, 2014 at 8:48 AM, Wodkowski, PawelX < pawelx.wodkowski@intel.com> wrote: > Refer to DPDK getting started guide paragraph 5.4. It might help. > Also it might be easier to do write simple application that send a packet > on port 1 and rx it on port 2 in separate threads on separate cores (simple > physical loop). You can then add timestamp and send packet back and see how > long it will take TX to RX and RX to TX process. > > Pawel Wodkowski > -------------------------------------------------------------- > Intel Shannon Limited > Registered in Ireland > Registered Office: Collinstown Industrial Park, Leixlip, County Kildare > Registered Number: 308263 > Business address: Dromore House, East Park, Shannon, Co. Clare > > This e-mail and any attachments may contain confidential material for the > sole use of the intended recipient(s). Any review or distribution by others > is strictly prohibited. If you are not the intended recipient, please > contact the sender and delete all copies. > > >