From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Miller Subject: Re: [PATH net-next] tcp: pause Fast Open globally after third consecutive timeout Date: Wed, 13 Dec 2017 15:51:38 -0500 (EST) Message-ID: <20171213.155138.401295393122455021.davem@davemloft.net> References: <20171212211040.222118-1-ycheng@google.com> Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org, edumazet@google.com, ncardwell@google.com, weiwan@google.com, cpaasch@apple.com, ddamjanovic@mozilla.com, mcmanus@ducksong.com To: ycheng@google.com Return-path: Received: from shards.monkeyblade.net ([184.105.139.130]:44882 "EHLO shards.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753825AbdLMUvl (ORCPT ); Wed, 13 Dec 2017 15:51:41 -0500 In-Reply-To: <20171212211040.222118-1-ycheng@google.com> Sender: netdev-owner@vger.kernel.org List-ID: From: Yuchung Cheng Date: Tue, 12 Dec 2017 13:10:40 -0800 > Prior to this patch, active Fast Open is paused on a specific > destination IP address if the previous connections to the > IP address have experienced recurring timeouts . But recent > experiments by Microsoft (https://goo.gl/cykmn7) and Mozilla > browsers indicate the isssue is often caused by broken middle-boxes > sitting close to the client. Therefore it is much better user > experience if Fast Open is disabled out-right globally to avoid > experiencing further timeouts on connections toward other > destinations. > > This patch changes the destination-IP disablement to global > disablement if a connection experiencing recurring timeouts > or aborts due to timeout. Repeated incidents would still > exponentially increase the pause time, starting from an hour. > This is extremely conservative but an unfortunate compromise to > minimize bad experience due to broken middle-boxes. > > Reported-by: Dragana Damjanovic > Reported-by: Patrick McManus > Signed-off-by: Yuchung Cheng > Reviewed-by: Wei Wang > Reviewed-by: Neal Cardwell > Reviewed-by: Eric Dumazet Very unfortunate, but I can't suggest anything better at this time. Applied, thank you.