From mboxrd@z Thu Jan 1 00:00:00 1970 From: =?UTF-8?B?QmrDtnJuIFTDtnBlbA==?= Subject: Re: [PATCH v2 0/5] Introducing ixgbe AF_XDP ZC support Date: Tue, 2 Oct 2018 20:39:25 +0200 Message-ID: References: <20181002080034.11754-1-bjorn.topel@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit Cc: jeffrey.t.kirsher@intel.com, intel-wired-lan@lists.osuosl.org, "Karlsson, Magnus" , Magnus Karlsson , Alexei Starovoitov , Daniel Borkmann , Linux Kernel Network Developers , Jesper Dangaard Brouer , Test , Jakub Kicinski To: William Tu , =?UTF-8?B?QmrDtnJuIFTDtnBlbA==?= Return-path: Received: from mga01.intel.com ([192.55.52.88]:26110 "EHLO mga01.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726274AbeJCBY0 (ORCPT ); Tue, 2 Oct 2018 21:24:26 -0400 In-Reply-To: Content-Language: en-US Sender: netdev-owner@vger.kernel.org List-ID: On 2018-10-02 20:23, William Tu wrote: > On Tue, Oct 2, 2018 at 1:01 AM Björn Töpel wrote: >> >> From: Björn Töpel >> >> Jeff: Please remove the v1 patches from your dev-queue! >> >> This patch set introduces zero-copy AF_XDP support for Intel's ixgbe >> driver. >> >> The ixgbe zero-copy code is located in its own file ixgbe_xsk.[ch], >> analogous to the i40e ZC support. Again, as in i40e, code paths have >> been copied from the XDP path to the zero-copy path. Going forward we >> will try to generalize more code between the AF_XDP ZC drivers, and >> also reduce the heavy C&P. >> >> We have run some benchmarks on a dual socket system with two Broadwell >> E5 2660 @ 2.0 GHz with hyperthreading turned off. Each socket has 14 >> cores which gives a total of 28, but only two cores are used in these >> experiments. One for TR/RX and one for the user space application. The >> memory is DDR4 @ 2133 MT/s (1067 MHz) and the size of each DIMM is >> 8192MB and with 8 of those DIMMs in the system we have 64 GB of total >> memory. The compiler used is GCC 7.3.0. The NIC is Intel >> 82599ES/X520-2 10Gbit/s using the ixgbe driver. >> >> Below are the results in Mpps of the 82599ES/X520-2 NIC benchmark runs >> for 64B and 1500B packets, generated by a commercial packet generator >> HW blasting packets at full 10Gbit/s line rate. The results are with >> retpoline and all other spectre and meltdown fixes. >> >> AF_XDP performance 64B packets: >> Benchmark XDP_DRV with zerocopy >> rxdrop 14.7 >> txpush 14.6 >> l2fwd 11.1 >> >> AF_XDP performance 1500B packets: >> Benchmark XDP_DRV with zerocopy >> rxdrop 0.8 >> l2fwd 0.8 >> >> XDP performance on our system as a base line. >> >> 64B packets: >> XDP stats CPU Mpps issue-pps >> XDP-RX CPU 16 14.7 0 >> >> 1500B packets: >> XDP stats CPU Mpps issue-pps >> XDP-RX CPU 16 0.8 0 >> >> The structure of the patch set is as follows: >> >> Patch 1: Introduce Rx/Tx ring enable/disable functionality >> Patch 2: Preparatory patche to ixgbe driver code for RX >> Patch 3: ixgbe zero-copy support for RX >> Patch 4: Preparatory patch to ixgbe driver code for TX >> Patch 5: ixgbe zero-copy support for TX >> >> Changes since v1: >> >> * Removed redundant AF_XDP precondition checks, pointed out by >> Jakub. Now, the preconditions are only checked at XDP enable time. >> * Fixed a crash in the egress path, due to incorrect usage of >> ixgbe_ring queue_index member. In v2 a ring_idx back reference is >> introduced, and used in favor of queue_index. William reported the >> crash, and helped me smoke out the issue. Kudos! > > Thanks! I tested this series and no more crash. Thank you for spending time on this! > The number is pretty good (*without* spectre and meltdown fixes) > model name : Intel(R) Xeon(R) CPU E5-2440 v2 @ 1.90GHz, total 16 cores/ > > AF_XDP performance 64B packets: > Benchmark XDP_DRV with zerocopy > rxdrop 20 > txpush 18 > l2fwd 20 > What is 20 here? Given that 14.8Mpps is maximum for 64B@10Gbit/s for one queue, is this multiple queues? Is this xdpsock or OvS with AF_XDP? Cheers, Björn > Regards, > William >