From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Miller Subject: Re: [PATCH 2/2] tcp: TLP loss detection. Date: Tue, 12 Mar 2013 08:45:22 -0400 (EDT) Message-ID: <20130312.084522.1295825068015762611.davem@davemloft.net> References: <1363032044-27315-1-git-send-email-nanditad@google.com> <1363032044-27315-2-git-send-email-nanditad@google.com> Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Cc: nanditad@google.com, ycheng@google.com, edumazet@google.com, netdev@vger.kernel.org, ilpo.jarvinen@cs.helsinki.fi, therbert@google.com To: ncardwell@google.com Return-path: Received: from shards.monkeyblade.net ([149.20.54.216]:51133 "EHLO shards.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932167Ab3CLMpL (ORCPT ); Tue, 12 Mar 2013 08:45:11 -0400 In-Reply-To: Sender: netdev-owner@vger.kernel.org List-ID: From: Neal Cardwell Date: Mon, 11 Mar 2013 17:38:12 -0400 > On Mon, Mar 11, 2013 at 4:00 PM, Nandita Dukkipati wrote: >> This is the second of the TLP patch series; it augments the basic TLP >> algorithm with a loss detection scheme. >> >> This patch implements a mechanism for loss detection when a Tail >> loss probe retransmission plugs a hole thereby masking packet loss >> from the sender. The loss detection algorithm relies on counting >> TLP dupacks as outlined in Sec. 3 of: >> http://tools.ietf.org/html/draft-dukkipati-tcpm-tcp-loss-probe-01 >> >> The basic idea is: Sender keeps track of TLP "episode" upon >> retransmission of a TLP packet. An episode ends when the sender receives >> an ACK above the SND.NXT (tracked by tlp_high_seq) at the time of the >> episode. We want to make sure that before the episode ends the sender >> receives a "TLP dupack", indicating that the TLP retransmission was >> unnecessary, so there was no loss/hole that needed plugging. If the >> sender gets no TLP dupack before the end of the episode, then it reduces >> ssthresh and the congestion window, because the TLP packet arriving at >> the receiver probably plugged a hole. >> >> Signed-off-by: Nandita Dukkipati > > Acked-by: Neal Cardwell Also applied, thanks.