From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pf1-f182.google.com (mail-pf1-f182.google.com [209.85.210.182]) by dpdk.org (Postfix) with ESMTP id 7B15F239 for ; Wed, 31 Oct 2018 16:25:17 +0100 (CET) Received: by mail-pf1-f182.google.com with SMTP id a15-v6so7801413pfn.0 for ; Wed, 31 Oct 2018 08:25:17 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=networkplumber-org.20150623.gappssmtp.com; s=20150623; h=date:from:to:cc:subject:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=QmVqAKHs7aNmk8qaM0Gw8bmoKUvj/rY5vcc15v0iO+w=; b=zNh6UT6pfGkMs8rfw8dmOcDdFd/oGeznCXojyAj2yknSWrpLXSEnwfejbGRf/MwILf 2ZPmpUfZPJ3wMhHJR27UJf4D7dddy4Q7s7CCDKoTiruicWwR8MzOpF/b3cttiR92yQRZ 7d9Cq49ub/fPDp/S5l/iTtRhM6u/mttUbCRVdV8MhwHAy3V/Yw3ATrWVwUz2iLkkLwqW zKoBYJ/oKzJrnzc/iHe171/SseroWcaD1Ze3Ofo7ULiXoja/oT9IXzfvmN+xH+t+Khkd LTfQ7GPtScgbnAtDgX0VfsIyTv0jbkHGO2b3ONGXSwRqEw9N5NjFhGsMQbBvWTs/mIBP pfyw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=QmVqAKHs7aNmk8qaM0Gw8bmoKUvj/rY5vcc15v0iO+w=; b=Rv/FGDFpq/ANYOGhQ5qsNO1G6eY/tnXpW3A9lmpht94Xa1kKqcU2Xsak/w7fnl0Ju6 fLl1MeRQJH0GQMgwfoEkuDNxi++UZX8pdEwZv6ho3txGJ1uErO03at99oSYPS5h/77oR TWgRN82hRP4DqJHtF7oGCfHv5XW0OOrnpN55691nE5qV9thaEjC6uVPv33NCnXh7rEQD tXYIQC+OKVJO8pC+Ri2AIGRP5dfzFaWNalYxgeuGdt9lGVy0u45oFcFL/7F0uG0mPMQe LNAECzLvkvBucukQQzMM78JY104U9tuWmUMFcora0rALfJ375PDR14yh0SRFj7gm8qPY Eh6g== X-Gm-Message-State: AGRZ1gKVpYrL4qRWjqOAH35KZLt73LmxWpedHmDfFM9ocHo1o4h0t0Fz zwOmWGBp2Jv/XP4A9rYsFh3Om06hPiQ= X-Google-Smtp-Source: AJdET5eyMB2vQuRYohed4i505g16EhR0C8zoaL/YrxW0SKObfsYAIyg5DHLbZmMG4JZeIFd8ML9NXw== X-Received: by 2002:a63:66c1:: with SMTP id a184-v6mr3714550pgc.26.1540999516369; Wed, 31 Oct 2018 08:25:16 -0700 (PDT) Received: from xeon-e3 (204-195-22-127.wavecable.com. [204.195.22.127]) by smtp.gmail.com with ESMTPSA id s186-v6sm44502420pfs.164.2018.10.31.08.25.16 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Wed, 31 Oct 2018 08:25:16 -0700 (PDT) Date: Wed, 31 Oct 2018 08:25:06 -0700 From: Stephen Hemminger To: "Nikos Anastopoulos" Cc: "users@dpdk.org" Message-ID: <20181031082506.68ab0c62@xeon-e3> In-Reply-To: <814f576a9d9cb240a1cddea3e2b913f9@iris> References: <814f576a9d9cb240a1cddea3e2b913f9@iris> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Subject: Re: [dpdk-users] Possibly wrong RX statistics reported by virtio driver (TRex generator) 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: , X-List-Received-Date: Wed, 31 Oct 2018 15:25:17 -0000 On Wed, 31 Oct 2018 10:29:38 +0200 "Nikos Anastopoulos" wrote: > Hi list, > > > > The TRex traffic generator's folks recommended us to contact you for an issue that might relate to DPDK virtio driver (https://groups.google.com/forum/#!topic/trex-tgn/LxtTV7G43AE). > > > > Specifically, our scenario involves running TRex inside a KVM instance with 2 vhost-user ports, which are connected in loopback mode via an OVS-DPDK (i.e. whatever sent through port1 goes to port2, and vice versa). We observe that the received traffic volume reported by TRex is much less than the transmitted (it is constantly 4B per packet), whereas: > > 1) the count of the received packets is the same > > 2) the contents of the received packets, as captured _inside_ the VM, are the same with the transmitted > > > > Specifically, we experimented with different packet sizes being transmitted, i.e. 64B, 150B, 1000B, yet in the receive path the reported incoming volume corresponded constantly to 4B-per-packet, for all cases. > > > > The TRex engineers suggested that it seems like an RX counters issues in virtio driver. > > > > Experimental setup: > > - TRex v2.45 (uses DPDK 17.11 AFAIK), within a QEMU v2.12 > > - on the host: OVS 2.10.0 with DPDK 17.11.3 > > > > Thanks, > > Niko No idea, try dumping a sample of packets in virtio_update_packet_stats