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=-1.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED autolearn=ham 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 BD885C4360F for ; Thu, 4 Apr 2019 14:00:03 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 927762082E for ; Thu, 4 Apr 2019 14:00:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729828AbfDDOAC (ORCPT ); Thu, 4 Apr 2019 10:00:02 -0400 Received: from www62.your-server.de ([213.133.104.62]:58588 "EHLO www62.your-server.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727255AbfDDOAC (ORCPT ); Thu, 4 Apr 2019 10:00:02 -0400 Received: from [78.46.172.2] (helo=sslproxy05.your-server.de) by www62.your-server.de with esmtpsa (TLSv1.2:DHE-RSA-AES256-GCM-SHA384:256) (Exim 4.89_1) (envelope-from ) id 1hC2ti-0006Pc-VJ; Thu, 04 Apr 2019 15:59:19 +0200 Received: from [2a02:120b:c3fc:feb0:dda7:bd28:a848:50e2] (helo=linux.home) by sslproxy05.your-server.de with esmtpsa (TLSv1.2:ECDHE-RSA-AES256-GCM-SHA384:256) (Exim 4.89) (envelope-from ) id 1hC2ti-000VT2-KB; Thu, 04 Apr 2019 15:59:18 +0200 Subject: Re: [PATCH net-next v2] tcp: Ensure DCTCP reacts to losses To: Neal Cardwell , "Tilmans, Olivier (Nokia - BE/Antwerp)" Cc: "De Schepper, Koen (Nokia - BE/Antwerp)" , Bob Briscoe , Lawrence Brakmo , Florian Westphal , Daniel Borkmann , Yuchung Cheng , Eric Dumazet , Andrew Shewmaker , Glenn Judd , "David S. Miller" , Alexey Kuznetsov , Hideaki YOSHIFUJI , "netdev@vger.kernel.org" , "linux-kernel@vger.kernel.org" References: <20190404121731.13917-1-olivier.tilmans@nokia-bell-labs.com> From: Daniel Borkmann Message-ID: Date: Thu, 4 Apr 2019 15:59:17 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.3.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 8bit X-Authenticated-Sender: daniel@iogearbox.net X-Virus-Scanned: Clear (ClamAV 0.100.3/25409/Thu Apr 4 09:53:59 2019) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 04/04/2019 03:55 PM, Neal Cardwell wrote: > On Thu, Apr 4, 2019 at 9:48 AM Neal Cardwell wrote: >> On Thu, Apr 4, 2019 at 8:24 AM Tilmans, Olivier (Nokia - BE/Antwerp) >> wrote: >>> >>> From: Koen De Schepper >>> >>> RFC8257 ยง3.5 explicitly states that "A DCTCP sender MUST react to >>> loss episodes in the same way as conventional TCP". >> ... >>> This patch replace the clamping of alpha by setting ssthresh to >>> half of cwnd for both fast retransmissions and RTOs, at most once >>> per RTT. Consequently, the dctcp_clamp_alpha_on_loss module parameter >>> has been removed. >> >> Acked-by: Neal Cardwell >> >> Thanks! > > FWIW, my vote is that this is an important bug fix that is appropriate > for the net branch and -stable releases, rather than net-next. Agree, my preference would be for -net tree as well. Thanks for the fix! Acked-by: Daniel Borkmann