From mboxrd@z Thu Jan 1 00:00:00 1970 From: Stephen Hemminger Subject: Re: How can I calculate/estimate pps(packet per seocond) and bps(bit per second) in DPDK pktg Date: Tue, 3 Nov 2015 14:05:31 -0800 Message-ID: <20151103140531.677eee6d@xeon-e3> References: <514E811C-1D85-4BB7-AA9C-C5D2B2ED6043@intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Cc: "dev@dpdk.org" To: "Van Haaren, Harry" Return-path: Received: from mail-pa0-f46.google.com (mail-pa0-f46.google.com [209.85.220.46]) by dpdk.org (Postfix) with ESMTP id 456D18E86 for ; Tue, 3 Nov 2015 23:05:21 +0100 (CET) Received: by pacdm15 with SMTP id dm15so5820541pac.3 for ; Tue, 03 Nov 2015 14:05:20 -0800 (PST) In-Reply-To: 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 Tue, 3 Nov 2015 14:30:41 +0000 "Van Haaren, Harry" wrote: > Hi Keith, > > > From: dev [mailto:dev-bounces@dpdk.org] On Behalf Of Wiles, Keith > > > Hmm, I just noticed I did not include the FCS bytes. Does the NIC include FCS bytes in the > > counters? Need to verify that one and if not then it becomes a bit more complex. > > The Intel NICs count packet sizes inclusive of CRC / FCS, from eg the ixgbe/82599 datasheet: > "This register includes bytes received in a packet from the field through the field, inclusively." > > -Harry IMHO this is a bug. Other drivers don't include the CRC, and the Intel driver only includes CRC in count for one direction, and depends on value of stripping flag. I sent a patch to fix this because our customers didn't like it when Rx != Tx bytes but there was somebody who liked including CRC. It really is a Cisco versus the world thing. Juniper/Linux/BSD all do NOT include CRC in counters and therefore that is what should be done.