From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wm0-f50.google.com (mail-wm0-f50.google.com [74.125.82.50]) by dpdk.org (Postfix) with ESMTP id 2F79029CB for ; Wed, 25 May 2016 11:28:00 +0200 (CEST) Received: by mail-wm0-f50.google.com with SMTP id s131so13222372wme.0 for ; Wed, 25 May 2016 02:28:00 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=6wind-com.20150623.gappssmtp.com; s=20150623; h=from:to:cc:subject:date:message-id:user-agent:in-reply-to :references:mime-version:content-transfer-encoding; bh=7kma+2ZKHzA4mSnUGwpyLYhjuzP2t1hhxoNG9Ydls0w=; b=h0BVgbcosfWjp8EoXbA0hA+/Rl2o9/L6E+77NilhHHIdniXzmEBb2VhDTt3UBShwYy oRN2FPZYkkgm42LFuaZxaeGGbguZstjRK5v2f9KNQhccC6eVi3Me2ShRvbmOym9M9QGL kiwlgWvJSNRb3DWMmAKw10xWfA/4dzPWY1sTqtqmLrR1DUTmES5a92IO1oGpPpVgvqKJ wblOl6piA6/XEduGyVVliZ/AC5hOx1zInpRlGdzN1vF50DJUeFDqa/qXGfLNLpStqAtO kTtZ55CL9LezEJxCvW1rfOBDxTx7yTn7Gx5THkG51H8Zi/oSMwlxgU2+akk6AJfGioPS YewA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:from:to:cc:subject:date:message-id:user-agent :in-reply-to:references:mime-version:content-transfer-encoding; bh=7kma+2ZKHzA4mSnUGwpyLYhjuzP2t1hhxoNG9Ydls0w=; b=mke88d6dHFIHKv1hLx+JuEsUL6Sv7IfOxDb2hzk4SBdMy1PI6T6Qp6etANkuNOj86r 4kfU8AmZoRYDpi8DOXozDsunGrP9civ3iivC5Cm8pItKWX59INaJY4w30sFoZLQoX8vd GG7h7FWAnDDErZGBX8/trIA1zFD+5bqh3WwOWia7/eXbkk7J5KV6qgL0zYfni0j+r5ey TdGrSA3QuVs1KZ0GTS9gaO4yJ3bmVtQs9I9P/EehzYynC+G0+hHHE2np3wUv2ecDlq3p yE9i8h+8Gbd00+A5+vNX1x4Lynmf/oj05hTcysne3buu1Q8/amCwymRzgc0lQVSGHOXg Aj3Q== X-Gm-Message-State: ALyK8tIYexIbwWIk2jQqxpIxspPRmuZu8R1glxjZclomTydjrzV5NsVZ8qinJnMQDCOHj46B X-Received: by 10.28.88.206 with SMTP id m197mr2253650wmb.43.1464168479900; Wed, 25 May 2016 02:27:59 -0700 (PDT) Received: from xps13.localnet (184.203.134.77.rev.sfr.net. [77.134.203.184]) by smtp.gmail.com with ESMTPSA id b22sm8205341wmb.9.2016.05.25.02.27.58 (version=TLSv1/SSLv3 cipher=OTHER); Wed, 25 May 2016 02:27:59 -0700 (PDT) From: Thomas Monjalon To: Pablo de Lara Cc: Zhihong Wang , dev@dpdk.org, konstantin.ananyev@intel.com, bruce.richardson@intel.com Date: Wed, 25 May 2016 11:27:58 +0200 Message-ID: <3881647.zch7p0jKfH@xps13> User-Agent: KMail/4.14.10 (Linux/4.1.6-1-ARCH; KDE/4.14.11; x86_64; ; ) In-Reply-To: <1462488421-118990-1-git-send-email-zhihong.wang@intel.com> References: <1462488421-118990-1-git-send-email-zhihong.wang@intel.com> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="us-ascii" Subject: Re: [dpdk-dev] [PATCH 0/6] vhost/virtio performance loopback utility 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: Wed, 25 May 2016 09:28:00 -0000 CC Pablo, testpmd maintainer Pablo, This patchset looks really valuable to improve performance debugging. Would you have time to dig into a review please? 2016-05-05 18:46, Zhihong Wang: > This patch enables vhost/virtio pmd performance loopback test in testpmd. > All the features are for general usage. > > The loopback test focuses on the maximum full-path packet forwarding > performance between host and guest, it runs vhost/virtio pmd only without > introducing extra overhead. > > Therefore, the main requirement is traffic generation, since there's no > other packet generators like IXIA to help. > > In current testpmd, io-fwd is the ideal candidate to perform this loopback > test because it's the fastest possible forwarding engine: Start testpmd > io-fwd in host with 1 vhost pmd port, and start testpmd io-fwd in the > connected guest with 1 corresponding virtio pmd port, and these 2 ports > form a forwarding loop, packets received by the host vhost pmd port are > forwarded to the guest virtio pmd port, and packets received by the guest > virtio pmd port are sent to the host vhost pmd port. > > As to traffic generation, "start tx_first" injects a burst of packets into > the loop, which is the ideal way to do that. > > However 2 issues remain: > > 1. If only 1 burst of packets are injected in the loop, there will > almost definitely be empty rx operations, e.g. When guest virtio pmd > port send burst to the host, then it starts the rx immediately, it's > likely the packets are still being forwarded by host vhost pmd port > and haven't reached the guest yet. > > We need to fill up the ring to keep all pmds busy. > > 2. io-fwd doesn't provide retry mechanism, so if packet loss occurs, > there won't be a full burst in the loop. > > To address these issues, this patch: > > 1. Add an io_retry-fwd in testpmd to prevent most packet losses. > > 2. Add parameter to enable configurable tx_first burst number. > > Other related improvements include: > > 1. Handle all rxqs when multiqueue is enabled: Current testpmd forces a > single core for each rxq which causes inconvenience and confusion. > > 2. Show topology at forwarding start: "show config fwd" also does this, > but show it directly can reduce the possibility of mis-configuration. > > 3. Add throughput information in port statistics display for "show port > stats (port_id|all)". > > Finally there's documentation update.