From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Miller Subject: Re: [PATCH] tcp: add setsockopt to disable slow start after idle Date: Sun, 11 Apr 2010 13:18:50 -0700 (PDT) Message-ID: <20100411.131850.226764423.davem@davemloft.net> References: <4BC06A5F.6070804@gmail.com> <20100410.154709.201110995.davem@davemloft.net> <4BC218B6.8050703@gmail.com> Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Cc: linux-kernel@vger.kernel.org, netdev@vger.kernel.org To: cristiklein@gmail.com Return-path: In-Reply-To: <4BC218B6.8050703@gmail.com> Sender: linux-kernel-owner@vger.kernel.org List-Id: netdev.vger.kernel.org From: Cristian KLEIN Date: Sun, 11 Apr 2010 20:45:10 +0200 > Without this patch, an application which needs this behaviour > (i.e. not to slow start after idle) is forced to implement its own > UDP-based protocol with all the congestion control, retransmission > etc. Undue congestion might still occur. Ask your system administrator to set the existing sysctl, because it is a physical network attribute whether this behavior is safe or not. And if it is safe, it is safe for all applications, there is no reason for one application to ask for it and others to not. If it's legal, it helps all applications without exception. Your attempts to tie this to NAGLE is complete nonsense. NAGLE changes acking behavior, whereas this feature controls in what way we trust congestion control information we've probed for in the past.