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=-3.6 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED 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 49BC1C433E3 for ; Thu, 20 Aug 2020 07:43:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 220102080C for ; Thu, 20 Aug 2020 07:43:35 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="iE8RIxO/" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726387AbgHTHnc (ORCPT ); Thu, 20 Aug 2020 03:43:32 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40498 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725797AbgHTHnb (ORCPT ); Thu, 20 Aug 2020 03:43:31 -0400 Received: from mail-ed1-x52e.google.com (mail-ed1-x52e.google.com [IPv6:2a00:1450:4864:20::52e]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D7CF7C061757; Thu, 20 Aug 2020 00:43:30 -0700 (PDT) Received: by mail-ed1-x52e.google.com with SMTP id i6so822265edy.5; Thu, 20 Aug 2020 00:43:30 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=dqghZRBtsmgBcL9zovjVe2f2vLQATQWo8uSmvuxBzHQ=; b=iE8RIxO/pFTAv5ttCWHqtyybVWLleG5KbeeliQ4MWAcj3Et6B9Mt+XJaaOYzns3aBF WbQx68Vkf31i98LizPvX+hHeT6uZs4Q4Qtu8egP9MT8smRjreJG33EFLD210FvYqRIv6 VyG/P+c2nTYjIWmCJBuyydQa2XFJObOKoP2r6KiT7Oem/H0j5w0VrvTLItdQdK7o/izy Z6rseArdFHX/+devGGumGlVE1hxFC5w3C5CdfUAec54mwpU8Ec5tG0bmEW5Pmpx2QrZO djC25HjaY4wNtDeVF6KQ9D9bXKivhfrUQKcCqFWMPDm5uY5s8okiQzuepgC/6IUb49yU /FmQ== 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=dqghZRBtsmgBcL9zovjVe2f2vLQATQWo8uSmvuxBzHQ=; b=KH87rDbICNp76BtUEpgaNJaxvxQqUNUPpe4q3AxgOXg46Tk1x2AzhIZMRDhk8Iolxd WCcHFlwq8uIF6paVJ5j5diz+J9OwSzHzSVKn2JG+DLbCMqYx0pmukatwjDo+ygAL9jXG pbaLJhDSLLbXZOOFa9sVeUE6e4n+vGrPzt2yFyGxMmjLCgy2BsnL32ud5sF5AUEsXd9i BbDj0jHkxFNEUy/6Ws5LIKk9/NtXDvIDZe/tb4IN5YKJMo9zlOP4e0aPZ9YDzhUahIck HtU9O8n4GaE5/sL1fFdDxbE5QeQoCcajCKJX494PbZMjKiJDgXjXJrpw3YqQs60QyHSJ MzEQ== X-Gm-Message-State: AOAM531t/c6Ld8Nc352w02FyOfs0zyRaUJnC601mXnG5lPU0f1pO0p2c 3C2YPJ+vhAk9256/r/XsKMtP9GFlEZqvWGXW8No= X-Google-Smtp-Source: ABdhPJwMbmcJ4NWOGrV3q85l7RlB6WidpEdoOwK1UBexXU20R7Z2Ht1elpiWU7rI7joz4LZw490sfSv6MHCKZI7tMFA= X-Received: by 2002:aa7:c513:: with SMTP id o19mr1640779edq.327.1597909409462; Thu, 20 Aug 2020 00:43:29 -0700 (PDT) MIME-Version: 1.0 References: <465a540e-5296-32e7-f6a6-79942dfe2618@netrounds.com> <20200623134259.8197-1-mzhivich@akamai.com> <1849b74f-163c-8cfa-baa5-f653159fefd4@akamai.com> <7fd86d97-6785-0b5f-1e95-92bc1da9df35@netrounds.com> <500b4843cb7c425ea5449fe199095edd5f7feb0c.camel@redhat.com> <25ca46e4-a8c1-1c88-d6a9-603289ff44c3@akamai.com> In-Reply-To: <25ca46e4-a8c1-1c88-d6a9-603289ff44c3@akamai.com> From: Jike Song Date: Thu, 20 Aug 2020 15:43:17 +0800 Message-ID: Subject: Re: Packet gets stuck in NOLOCK pfifo_fast qdisc To: Josh Hunt Cc: Paolo Abeni , Jonas Bonn , Cong Wang , Michael Zhivich , David Miller , John Fastabend , LKML , Linux Kernel Network Developers , kehuan.feng@gmail.com Content-Type: text/plain; charset="UTF-8" Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Hi Josh, On Fri, Jul 3, 2020 at 2:14 AM Josh Hunt wrote: {snip} > Initial results with Cong's patch look promising, so far no stalls. We > will let it run over the long weekend and report back on Tuesday. > > Paolo - I have concerns about possible performance regression with the > change as well. If you can gather some data that would be great. If > things look good with our low throughput test over the weekend we can > also try assessing performance next week. > We met possibly the same problem when testing nvidia/mellanox's GPUDirect RDMA product, we found that changing NET_SCH_DEFAULT to DEFAULT_FQ_CODEL mitigated the problem, having no idea why. Maybe you can also have a try? Besides, our testing is pretty complex, do you have a quick test to reproduce it? -- Thanks, Jike