From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mga11.intel.com (mga11.intel.com [192.55.52.93]) by dpdk.org (Postfix) with ESMTP id EA747C450 for ; Tue, 30 Jun 2015 05:15:35 +0200 (CEST) Received: from fmsmga003.fm.intel.com ([10.253.24.29]) by fmsmga102.fm.intel.com with ESMTP; 29 Jun 2015 20:15:34 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.15,374,1432623600"; d="scan'208";a="516308394" Received: from orsmsx108.amr.corp.intel.com ([10.22.240.6]) by FMSMGA003.fm.intel.com with ESMTP; 29 Jun 2015 20:15:34 -0700 Received: from orsmsx154.amr.corp.intel.com (10.22.226.12) by ORSMSX108.amr.corp.intel.com (10.22.240.6) with Microsoft SMTP Server (TLS) id 14.3.224.2; Mon, 29 Jun 2015 20:15:33 -0700 Received: from FMSMSX109.amr.corp.intel.com (10.18.116.9) by ORSMSX154.amr.corp.intel.com (10.22.226.12) with Microsoft SMTP Server (TLS) id 14.3.224.2; Mon, 29 Jun 2015 20:15:32 -0700 Received: from fmsmsx113.amr.corp.intel.com ([169.254.13.28]) by FMSMSX109.amr.corp.intel.com ([169.254.15.204]) with mapi id 14.03.0224.002; Mon, 29 Jun 2015 20:15:31 -0700 From: "Wiles, Keith" To: "Jiang, Yunhong" , "dev@dpdk.org" Thread-Topic: [dpdk-dev] Why pktgen-dpdk will receive more packet than sent Thread-Index: AQHQsuMFtrybsupowEmqXIzNPFNTPA== Date: Tue, 30 Jun 2015 03:15:31 +0000 Message-ID: Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-originating-ip: [10.254.54.69] Content-Type: text/plain; charset="us-ascii" Content-ID: Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Subject: Re: [dpdk-dev] Why pktgen-dpdk will receive more packet than sent 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: Tue, 30 Jun 2015 03:15:36 -0000 On 6/29/15, 9:01 PM, "dev on behalf of Jiang, Yunhong" wrote: >Hi, all > I'm trying to test the l2fwd throughput using >https://github.com/pktgen/Pktgen-DPDK/blob/master/dpdk/examples/pktgen/scr >ipts/rfc2544.lua . However, the pktgen will receive more packets than it >sent out like " Total sent 14786446 recv 14786597, delta 151". I'm really >confused why this will happen. I have the pktgen machine and l2fwd >machine connected to each other directly and bind the igb_uio to the NIC >devices. > >Pktgen> *** Test packet size 64 at rate 100% >Total sent 133856261 recv 131517412, delta -2338849 >*** Test packet size 64 at rate 50% >Total sent 40208555 recv 40207420, delta -1135 >*** Test packet size 64 at rate 25% >PMD: ixgbe_set_rx_function(): Vector rx enabled, please make sure RX >burst size no less than 32. >Total sent 14786446 recv 14786597, delta 151 >*** Test packet size 64 at rate 37% >PMD: ixgbe_set_rx_function(): Vector rx enabled, please make sure RX >burst size no less than 32. >Total sent 26824256 recv 26823587, delta -669 The number of packets sent/recv are read from the NIC counters and Pktgen does not count the packets in anyway. The script could also be in error. I was just looking at the script and maybe the timing from stoping the transmit and reading the counters is the issue. You could try putting a delay before the counter read to make sure all of the packets have been sent/recv along with the reading of the packets. I do not have a setup to test it at this time. Regards, ++Keith > >Any hints will be really helpful, thanks! > >Thanks >--jyh