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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9CA66C433F5 for ; Mon, 9 May 2022 08:09:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229897AbiEIINP (ORCPT ); Mon, 9 May 2022 04:13:15 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54588 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237628AbiEIIFi (ORCPT ); Mon, 9 May 2022 04:05:38 -0400 Received: from mail-wr1-x429.google.com (mail-wr1-x429.google.com [IPv6:2a00:1450:4864:20::429]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5F71B15EA5F; Mon, 9 May 2022 01:01:35 -0700 (PDT) Received: by mail-wr1-x429.google.com with SMTP id u3so18239865wrg.3; Mon, 09 May 2022 01:01:35 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc:content-transfer-encoding; bh=2xFvAUu2Mi5eQC7Ozo69GKucsTfJHJ60BEy3d9RaYNk=; b=QTYEuxBrySeygqE9/VtZUARHlYpRUDDnHJiufCAnDQhgtCNlt0G8xsngJxuGBaAzM+ N3gwfHjWe1p7X+qUQ3yjBqrH1cktJIvXSvA/DVvOtPwoNwe6vg2DuQqqN/nGXbt/0L1k dcfoNd1TQLoD7jDONs/CnCcLYvVtLwdhVs4U/KAzH/F2fZ597lmFLyc5IJje0mRXRrjj BP4s3SSfHKC3mAE88m/qQ+lx1e5mSyVMHQhQ0nzf3hPANLsqNGARitzLS5ilZlf2s9Dt VcYQn81XEOrdsrHTQt/l0C3qkH4KsKIXl7c+QnuYsEYCKUPvBn2Ps+DZWbxyLL4UPp3X KOmA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc:content-transfer-encoding; bh=2xFvAUu2Mi5eQC7Ozo69GKucsTfJHJ60BEy3d9RaYNk=; b=eYlfF6IRkPUXTbkdsbNxqaLsP0Y0cm3hnhIgoauwBU2lAXwqVmptW/Xyw0iNj23lZR yR+gydFpc7oUgS32c9rthZCYy3TenOfHBCjbOXuGu/NRT1x9zkow7SLTFB/Moh5XYWIa ncD0AeyENTF/ZdPAy4HIxyYr2SVi0lAKw8qmM8J7O8F6XKbla/rtrqs3z/EhWPBnN4VM LBCg4/u1l3PtkcsFHZ4QdCPtO2+olAyOmQ/wZSJOcPzl63dUT2/uW5dfV2+dtnAj3nNM QoqEijqo8yNuwmF0NXU7buah5gGgcwF+wh2RdX5hhh2MLjbZFxKoadAGSzAVmPRBuPCU HTlA== X-Gm-Message-State: AOAM530gQG13wmU+RlVZYjHiHF3vlAl5gB/pFR/HTi8YvzEBsZ02T3Rv qapVb5+OrVYFta8n6e2ouAHyPS/L2mDqrH52G6mOSn9wVHGQLw== X-Google-Smtp-Source: ABdhPJwDlmtMZ5dUkpujCx+0M1K6rytzDgpjReAOAEEoDP6/0eGSTUfB3xMJevDLkZRohPi0uFJ8i5YU+cUEgDrP0Dg= X-Received: by 2002:a17:907:7296:b0:6e8:97c1:a7ef with SMTP id dt22-20020a170907729600b006e897c1a7efmr13221254ejc.262.1652082819903; Mon, 09 May 2022 00:53:39 -0700 (PDT) MIME-Version: 1.0 References: In-Reply-To: From: Dave Taht Date: Mon, 9 May 2022 00:53:28 -0700 Message-ID: Subject: Re: [PATCH RFC v1 net-next 1/4] net: Introduce Qdisc backpressure infrastructure To: Peilin Ye Cc: "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Hideaki YOSHIFUJI , David Ahern , Jamal Hadi Salim , Cong Wang , Jiri Pirko , Peilin Ye , Linux Kernel Network Developers , LKML , Cong Wang Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org I am very pleased to see this work. However, my "vision" such as it was, and as misguided as it might be, was to implement a facility similar to tcp_notsent_lowat for udp packets, tracking the progress of the udp packet through the kernel, and supplying backpressure and providing better information about where when and why the packet was dropped in the stack back to the application. I've been really impressed by the DROP_REASON work and had had no clue prior to seeing all that instrumentation, where else packets might be dropped in the kernel. I'd be interested to see what happens with sch_cake. --=20 FQ World Domination pending: https://blog.cerowrt.org/post/state_of_fq_code= l/ Dave T=C3=A4ht CEO, TekLibre, LLC