From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751490AbVKISh7 (ORCPT ); Wed, 9 Nov 2005 13:37:59 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751495AbVKISh7 (ORCPT ); Wed, 9 Nov 2005 13:37:59 -0500 Received: from mail.kroah.org ([69.55.234.183]:11421 "EHLO perch.kroah.org") by vger.kernel.org with ESMTP id S1751490AbVKISh4 (ORCPT ); Wed, 9 Nov 2005 13:37:56 -0500 Date: Wed, 9 Nov 2005 10:36:51 -0800 From: Greg KH To: linux-kernel@vger.kernel.org, stable@kernel.org, Arnaldo Carvalho de Melo , "David S. Miller" , netdev@vger.kernel.org Cc: Justin Forbes , Zwane Mwaikambo , "Theodore Ts'o" , Randy Dunlap , Chuck Wolber , torvalds@osdl.org, akpm@osdl.org, alan@lxorguk.ukuu.org.uk Subject: [patch 05/11] tcp: BIC max increment too large Message-ID: <20051109183651.GF3670@kroah.com> References: <20051109182205.294803000@press.kroah.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline; filename="tcp-bic-max-increment-too-large.patch" In-Reply-To: <20051109183614.GA3670@kroah.com> User-Agent: Mutt/1.5.11 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org From: Stephen Hemminger The max growth of BIC TCP is too large. Original code was based on BIC 1.0 and the default there was 32. Later code (2.6.13) included compensation for delayed acks, and should have reduced the default value to 16; since normally TCP gets one ack for every two packets sent. The current value of 32 makes BIC too aggressive and unfair to other flows. Submitted-by: Injong Rhee Signed-off-by: Stephen Hemminger Signed-off-by: Greg Kroah-Hartman --- net/ipv4/tcp_bic.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- linux-2.6.14.1.orig/net/ipv4/tcp_bic.c +++ linux-2.6.14.1/net/ipv4/tcp_bic.c @@ -27,7 +27,7 @@ */ static int fast_convergence = 1; -static int max_increment = 32; +static int max_increment = 16; static int low_window = 14; static int beta = 819; /* = 819/1024 (BICTCP_BETA_SCALE) */ static int low_utilization_threshold = 153; --