From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from dpdk.org (dpdk.org [92.243.14.124]) by inbox.dpdk.org (Postfix) with ESMTP id 48674A0471 for ; Tue, 13 Aug 2019 15:35:42 +0200 (CEST) Received: from [92.243.14.124] (localhost [127.0.0.1]) by dpdk.org (Postfix) with ESMTP id A19D31BDAC; Tue, 13 Aug 2019 15:35:41 +0200 (CEST) Received: from mail.deltatec.be (mxbackup1.deltatec.be [62.197.119.12]) by dpdk.org (Postfix) with ESMTP id AF514378B for ; Tue, 13 Aug 2019 15:35:40 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=deltacast.tv; s=AnsUTM; h=MIME-Version:Content-Type:Message-ID:Date:Subject:To:From; bh=gpnLYvPRbSJjbDCMZrWfyr6hOaZOzC9O3H/5PrazCkY=; b=BEdor0P95bzdLxlG7jINhDxdNgmPh5hOAV4PT9FELy0dNY9Q3Rd5dazroZDmOzNAbKW538gXRhGbKjBMIyRLdN8X6HiJiBok4mkz27fNmzTPInZUDLW8GrnLGD+8FEsTjvx0Byk9+rbn7TgHSXSg4QQZRpZ4vyyGxJUG7qTbiHM=; Received: from [172.16.4.5] (port=60823 helo=W2K16-SVR-5.office.deltatec.net) by mail.deltatec.be with esmtps (TLSv1.2:AES256-GCM-SHA384:256) (Exim 4.82_1-5b7a7c0-XX) (envelope-from ) id 1hxWxd-0001WA-32 for users@dpdk.org; Tue, 13 Aug 2019 15:35:38 +0200 Received: from W2K16-SVR-5.office.deltatec.net (172.16.4.5) by W2K16-SVR-5.office.deltatec.net (172.16.4.5) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.1034.26; Tue, 13 Aug 2019 15:35:37 +0200 Received: from W2K16-SVR-5.office.deltatec.net ([::1]) by W2K16-SVR-5.office.deltatec.net ([::1]) with mapi id 15.01.1034.026; Tue, 13 Aug 2019 15:35:37 +0200 X-CTCH-RefID: str=0001.0A0B0206.5D52BCAA.0004, ss=1, re=0.000, recu=0.000, reip=0.000, cl=1, cld=1, fgs=0 From: Antoine POLLENUS To: "users@dpdk.org" Thread-Topic: KNI RX/TX Jitter non symmetrical Thread-Index: AdVR1uWoKG1/b/IYQyWUDXamRpWMAw== Date: Tue, 13 Aug 2019 13:35:37 +0000 Message-ID: <0875400a43e44fbaa8a25e2d22f713ad@deltacast.tv> Accept-Language: fr-BE, en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-originating-ip: [172.16.6.165] MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable X-Content-Filtered-By: Mailman/MimeDel 2.1.15 Subject: [dpdk-users] KNI RX/TX Jitter non symmetrical X-BeenThere: users@dpdk.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: DPDK usage discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: users-bounces@dpdk.org Sender: "users" Hello, I'm testing the KNI with iperf and I discovered something strange. RX KNI a= nd TX KNI seems to not be symmetrical (in term of latency jitter) and I don= 't understand why. I'm using iperf with low packet rate: This command is launch from a machine that is not running DPDK connected in= point to point to a machine using a KNI interface: sudo iperf -c 10.0.0.2 -u -i 1 -t 3000 -l 54 -b 10368b -f b and the iperf server is launched on the machine with the KNI interface sudo iperf -s -u -i 1 And when I look at the jitter. The Jitter is always around 2.5ms but when I launch sudo iperf -c 10.0.0.2 -u -i 1 -t 3000 -l 54 -b 10368b -f b on the machine with the KNI interface and the server sudo iperf -s -u -i 1 on the non DPDK machine I have Jitter at around 0.002ms Can someone explain me what is the reason of this huge difference in term o= f jitter ? Regards, Antoine Pollenus