From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pf0-f181.google.com (mail-pf0-f181.google.com [209.85.192.181]) by dpdk.org (Postfix) with ESMTP id 8FD9DF94 for ; Tue, 18 Apr 2017 01:47:19 +0200 (CEST) Received: by mail-pf0-f181.google.com with SMTP id i5so72151413pfc.2 for ; Mon, 17 Apr 2017 16:47:19 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:in-reply-to:references:from:date:message-id:subject:to :cc; bh=jTCi/4MNor1E0FMLzNmGF1hyrCP43fdEBNjbSaPzkCQ=; b=VU/H7ZbjyiYhh3/dwAJxo+3XUrq3nZEVRyEioN6Mweq10Ek5KKStpMkQoY5NFk56N0 7tu23cLs36m+jn+cQCgstkXx8DIzp0yOaMzc1wqYXg3wODhsWMm3Myt+zuLc4dA1LY45 K9M9cGBUivhtODUR0YY4NTCCNIxpTTRtOFG3voO+fmNqPB6biLF/+QS1wkiQA50NFqDi +MWRbeQ1PdRYCPehSLKFk3xaK5kbK6IcDHtsddPHPvVxEa6PQVMhsW4uJKlMWvIb+saO +K5x+AScppAAC1Qoxbpc15GvqRe4TKxh+CS9/EJdcPgF9IUB14ibLAoG4LlLEgbfB2d7 Kd1g== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:in-reply-to:references:from:date :message-id:subject:to:cc; bh=jTCi/4MNor1E0FMLzNmGF1hyrCP43fdEBNjbSaPzkCQ=; b=uRfFLOsRW1nPVE64IDpXtTBdFBuOV3yz3in4/NGZ55HPq2JxrqemYsX8e1ybwYGEEt tiyP54yZcf00XlB83+dm8C/41UPqE0fXrq+lMquIrif0BN/ciQdZGH0OLh75HQ8wJ9r5 G8OMVKnXlLyqeXpif8x+9VxCAq3GL9PEzSNxpfoy5009kLbry/70FUD1QJkmlCNCAjqm 3qHtEupiKWef9TVS1fJ8KAqFy9q0N+PgOLxqivfepw5P/b4A2Zx9P5u3+OMQWlUoi9Nt 3z+2+ATe8oFnfghwt5E0dztr1xqmXvCim1Yba2Rl+MHNVXAe2E3zUYUeTv5ipvSZP6r5 knFA== X-Gm-Message-State: AN3rC/5ekY16TkRDkWcwtLeMycCdtXjfx4nFv11ToCX6G8QI3wljYREV W8+DwMdDpy2bioFoOF9+b3tLGQ+qZQ== X-Received: by 10.99.115.30 with SMTP id o30mr6346823pgc.155.1492472838850; Mon, 17 Apr 2017 16:47:18 -0700 (PDT) MIME-Version: 1.0 Received: by 10.100.155.13 with HTTP; Mon, 17 Apr 2017 16:47:18 -0700 (PDT) In-Reply-To: <2601191342CEEE43887BDE71AB9772583FAE9B8A@IRSMSX109.ger.corp.intel.com> References: <2601191342CEEE43887BDE71AB9772583FAE9B8A@IRSMSX109.ger.corp.intel.com> From: Ravi Kerur Date: Mon, 17 Apr 2017 16:47:18 -0700 Message-ID: To: "Ananyev, Konstantin" Cc: "dev@dpdk.org" Content-Type: text/plain; charset=UTF-8 X-Content-Filtered-By: Mailman/MimeDel 2.1.15 Subject: Re: [dpdk-dev] Q on IXGBE and I40E vector Tx processing X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 17 Apr 2017 23:47:20 -0000 Hi Konstantin, On Sun, Apr 16, 2017 at 3:26 PM, Ananyev, Konstantin < konstantin.ananyev@intel.com> wrote: > > Hi Ravi, > > > > > Hi, > > > > The reason I am asking I because I have tried different combinations of > > scalar and vector Tx and Rx processing for both IXGBE and I40E with > > following results > > > > 1. Vector Rx and Vector Tx gives best performance but can only support > > packet size of less than or equal to 2048 bytes > > > > 2. Scalar Rx and Scalar Tx works for all packet size but with degraded > > performance > > > > 3. Vector Rx and Scalar Tx (with certain PMD configuration) works fine > > (performance doesn't meet '1') but it has an inherent bug for packet size > > 8192 bytes as PMD stops packet processing > > > > From the code I see both IXGBE and I40E can support scattered vector Rx, > I > > am curious to know any obvious reasons scattered vector Tx support is > left > > out and does it make sense to implement it? > > > > If it makes sense to implement scattered vector Tx and Intel team hasn't > > worked on it I would like to make an attempt at it so kindly let me know. > > > > Yes, right now there is a tradeoff - simple TX functions (both vector and > scalar) are much > faster than full-featured TX function, but don't support any TX offloads > or multi-segs. > If you'd like to provide a patch that would add some TX offloads to the > simple path > without any performance degradation or either a patch that would improve > performance > of full-featured TX function - I am pretty sure such patches would be > welcomed. > Let me work on it and get back to you for any questions for clarifications. Thanks, > Konstantin > > >