From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.4 required=3.0 tests=DKIMWL_WL_MED,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,USER_IN_DEF_DKIM_WL autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id C0900C10F25 for ; Fri, 6 Mar 2020 16:16:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 97FC7208C3 for ; Fri, 6 Mar 2020 16:16:52 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="crvnJ2PS" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726314AbgCFQQw (ORCPT ); Fri, 6 Mar 2020 11:16:52 -0500 Received: from mail-ed1-f65.google.com ([209.85.208.65]:40465 "EHLO mail-ed1-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725873AbgCFQQv (ORCPT ); Fri, 6 Mar 2020 11:16:51 -0500 Received: by mail-ed1-f65.google.com with SMTP id a13so3139944edu.7 for ; Fri, 06 Mar 2020 08:16:50 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=6Dap1kc1qiXmbZugAe2o1JqyM0eTLYcQXaxHWvf2Qr8=; b=crvnJ2PSX5ggVaj+80DEgKsvarhTWwcMoI+N7ZC5iu8gm2lV6mIINrQdAKkUSe645q 1A2xLnhM0rYLSZRRM2vByGfv63PoXMgHNYyhTgF1jbk+RuOJrth+rt/+v80+RSjGfyHO DD8cIT6XcoScNsZQmP5AQQsacUKtJx2aYvwgTjvLgbnNtvn7QwUKRN/dwaINYiGV+9Kk J1fpu+16yIcHcAQZ7OcqxYX/kloQGwVenvXWj4yUBgm3MgW8xHCS6C6vZjNi0OKMpxvM QWkLvsNLaC1rvdhDH8ZUF17KFvM8zrIKBG/2is6vx7BkNW0RgcJz/j/HUk51elSuHYUQ BF6g== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=6Dap1kc1qiXmbZugAe2o1JqyM0eTLYcQXaxHWvf2Qr8=; b=sam9QMFJ8V4s03LzdgouXc7n+4PTa0iC9mbgggIaDUx6xoLHg7KI+EXB3SG7XOhQII nO39OGLax5mWbTBLne9Snj7Um9dgXKudxWkwe9eLqZObRR5Oosvi1Q0WjZVhHKNaOxcr X7c1gvAjalNZFfLhie07eJ3mG4kghtMR3q9OC/pcmpHDF/1cSLe9v4QT2RepnJnrc+69 Ky7nMMtmFp7ddub8dvT2UwDgWB1eyCznfYWJf6J2MC6mIz8i6s58DOXeb3LbHgdd98Kk 9rqeZRYndCENvprHO+ggASpUHAGHzN3oAeacZTov7hr82XbjDIwb5FbmHKDaXlr83ymF xb5A== X-Gm-Message-State: ANhLgQ1LCxT3pie+xo9ueJ49WCSUgPu93kjWRJ/ypz/rPxKBjLxQrkDe GENAeK0r/Axsr3zIGEfejyH1uYmmHrxe01k89dTqcg== X-Google-Smtp-Source: ADFU+vtEBorqMGpAvx/lz0TjI8aL/1bRpAFzeQnJglZFtVSKM2Ic7kyQA+cbQPzHfBniT9bOq7NfEsXupa/zAnOu+Bg= X-Received: by 2002:a17:906:15c2:: with SMTP id l2mr3568358ejd.302.1583511409398; Fri, 06 Mar 2020 08:16:49 -0800 (PST) MIME-Version: 1.0 References: <158323601793.2048441.8715862429080864020.stgit@firesoul> <20200303184350.66uzruobalf3y76f@ast-mbp> <5e62750bd8c9f_17502acca07205b42a@john-XPS-13-9370.notmuch> In-Reply-To: <5e62750bd8c9f_17502acca07205b42a@john-XPS-13-9370.notmuch> From: Luigi Rizzo Date: Fri, 6 Mar 2020 17:16:38 +0100 Message-ID: Subject: Re: [bpf-next PATCH] xdp: accept that XDP headroom isn't always equal XDP_PACKET_HEADROOM To: John Fastabend Cc: Alexei Starovoitov , Jesper Dangaard Brouer , bpf@vger.kernel.org, gamemann@gflclan.com, Network Development , Daniel Borkmann , Alexander Duyck , Ilias Apalodimas , =?UTF-8?B?VG9rZSBIw7hpbGFuZC1Kw7hyZ2Vuc2Vu?= Content-Type: text/plain; charset="UTF-8" Sender: bpf-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org On Fri, Mar 6, 2020 at 5:06 PM John Fastabend wrote: > > Alexei Starovoitov wrote: > > On Tue, Mar 03, 2020 at 12:46:58PM +0100, Jesper Dangaard Brouer wrote: ... > > > Tested on ixgbe with xdp_rxq_info --skb-mode and --action XDP_DROP: > > > - Before: 4,816,430 pps > > > - After : 7,749,678 pps > > > (Note that ixgbe in native mode XDP_DROP 14,704,539 pps) > > > > > But why do we care about generic-XDP performance? Seems users should > just use XDP proper on ixgbe and i40e its supported. I think the point was to show the performance benefit of skipping the normalization (admittedly for a specific workload, tinygrams; my other patch to control xdpgeneric_linearize covered a different range of packet sizes). On a side note I think it would be more useful to report times in ns/pkt, as they can be applied to other drivers too. Specifically here I would have written: Before: average 207 ns/pkt (1s / 4.816 Mpps) After: average 129 ns/pkt (1s / 7.750 Mpps) cheers luigi