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=-2.1 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 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 ADEFEC742A5 for ; Fri, 12 Jul 2019 07:05:09 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7D2E02084B for ; Fri, 12 Jul 2019 07:05:09 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="h+yoBxXM" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726095AbfGLHFI (ORCPT ); Fri, 12 Jul 2019 03:05:08 -0400 Received: from mail-wm1-f67.google.com ([209.85.128.67]:52279 "EHLO mail-wm1-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725840AbfGLHFI (ORCPT ); Fri, 12 Jul 2019 03:05:08 -0400 Received: by mail-wm1-f67.google.com with SMTP id s3so7831148wms.2 for ; Fri, 12 Jul 2019 00:05:06 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=subject:to:cc:references:from:message-id:date:user-agent :mime-version:in-reply-to:content-language:content-transfer-encoding; bh=4WVzx7NfYyKZfRHivTOMoWMwW7LfE1/XJK47R8mLMc8=; b=h+yoBxXMRuTmzR5u0kXhblKrczuUGvtKB8+2YDlvQo7121nvUvf8NNvg4aXHpay25M FKOOCQKc+MtQoeMm3mTyo36WfVYBg5S6Clp8718Gb5BRpT3W0w1If9g54kfZJTD1PyTG kH/qVmLU+/daPOoNixwFW7a88d3fKsXgEttgkgkufz7Ckb+fxBPY8OAJFwo27tlWxDw6 Z3VcUH6EVkogewGMhU+2G7kRulV9zC6DkNOeNdt8noIv5bDpdIdf26b+K+HZR0HzdzHS wbWddWgm8iJ4WMgEukZVpsGuSO1g2c9PR27o8pZjmj5tGy9RRfTM9cS2NVd91cyhNeTa qw2A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:cc:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=4WVzx7NfYyKZfRHivTOMoWMwW7LfE1/XJK47R8mLMc8=; b=KGD7RDRKdcSKmBLFRn9qvwtTOeaDiSqIXJ+icfJyq2xCpZAgmyKG+twgZ4iIGmQK+G AAyXHE3ZO2lzguqvwaRueC3Cj0mS2xIKOvEi3umZ32j5Mv3OpxWHm6Mg/Sxsjo4CiE/A J0nXAgkaVQnVGHEhBf4npgyR6ulWMyp15X1ARCys/vIFFz1KJDBIqEB+wmxNKKx42N+W UWBlEM2FPbN92j1HdxQygYKLmAc9bBBHWQLPa+j9gLv9RNCakdQbMJfUpN+vqwO6Ok6Z kUmTYtURYsUBA+MHn0Q/DIde8vZmihRqyGqwHgxG5YIoxsJfdXnNvlEgYzXlyVweLwlM Adog== X-Gm-Message-State: APjAAAV2rGhvqieHeTaFxcPkakhtdyRRXGo1Y8eArCXZcSx8AjX+0li+ 08gJbIU+hmpoRsdWBFy2O74= X-Google-Smtp-Source: APXvYqzzNRBTFe/6QHlQEt60AsVg5m+NItvoGu7ALu9okOoaccGLeMEO+mQ3uZ1h/AAKScXlZbhm+g== X-Received: by 2002:a1c:720e:: with SMTP id n14mr7977685wmc.53.1562915106248; Fri, 12 Jul 2019 00:05:06 -0700 (PDT) Received: from [192.168.8.147] (106.174.185.81.rev.sfr.net. [81.185.174.106]) by smtp.gmail.com with ESMTPSA id k124sm11158933wmk.47.2019.07.12.00.05.04 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Fri, 12 Jul 2019 00:05:05 -0700 (PDT) Subject: Re: [PATCH net 2/4] tcp: tcp_fragment() should apply sane memory limits To: Jonathan Lemon , Eric Dumazet Cc: "Prout, Andrew - LLSC - MITLL" , Christoph Paasch , "David S . Miller" , netdev , Greg Kroah-Hartman , Jonathan Looney , Neal Cardwell , Tyler Hicks , Yuchung Cheng , Bruce Curtis , Dustin Marquess References: <20190617170354.37770-1-edumazet@google.com> <20190617170354.37770-3-edumazet@google.com> <03cbcfdf-58a4-dbca-45b1-8b17f229fa1d@gmail.com> <63cd99ed3d0c440185ebec3ad12327fc@ll.mit.edu> <96791fd5-8d36-2e00-3fef-60b23bea05e5@gmail.com> <4B9799E0-A736-4944-9BF3-FBACCFBDCCC5@gmail.com> From: Eric Dumazet Message-ID: Date: Fri, 12 Jul 2019 09:05:03 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.7.1 MIME-Version: 1.0 In-Reply-To: <4B9799E0-A736-4944-9BF3-FBACCFBDCCC5@gmail.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 8bit Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On 7/11/19 9:04 PM, Jonathan Lemon wrote: > I discovered we have some production services that set SO_SNDBUF to > very small values (~4k), as they are essentially doing interactive > communications, not bulk transfers.  But there's a difference between > "terrible performance" and "TCP stops working". You had a copy of these patches month ago, yet you discovered this issue today ? I already said I was going to work on the issue, no need to add pressure on me, I had enough of it already.