From mboxrd@z Thu Jan 1 00:00:00 1970 From: Stephen Hemminger Subject: [PATCH 3/7] tcp_cubic: make ack train delta value a parameter Date: Mon, 14 Mar 2011 10:52:14 -0700 Message-ID: <20110314175439.471612260@vyatta.com> References: <20110314175211.788224699@vyatta.com> Cc: netdev@vger.kernel.org To: "David S. Miller" Return-path: Received: from suva.vyatta.com ([76.74.103.44]:58244 "EHLO suva.vyatta.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757051Ab1CNSCD (ORCPT ); Mon, 14 Mar 2011 14:02:03 -0400 Content-Disposition: inline; filename=tcp-cubic-ackdelta.patch Sender: netdev-owner@vger.kernel.org List-ID: Make the spacing between ACK's that indicates a train a tuneable value like other hystart values. Signed-off-by: Stephen Hemminger --- a/net/ipv4/tcp_cubic.c 2011-03-14 08:19:15.697936023 -0700 +++ b/net/ipv4/tcp_cubic.c 2011-03-14 08:19:18.361944814 -0700 @@ -52,6 +52,7 @@ static int tcp_friendliness __read_mostl static int hystart __read_mostly = 1; static int hystart_detect __read_mostly = HYSTART_ACK_TRAIN | HYSTART_DELAY; static int hystart_low_window __read_mostly = 16; +static int hystart_ack_delta __read_mostly = 2; static u32 cube_rtt_scale __read_mostly; static u32 beta_scale __read_mostly; @@ -75,6 +76,8 @@ MODULE_PARM_DESC(hystart_detect, "hyrbri " 1: packet-train 2: delay 3: both packet-train and delay"); module_param(hystart_low_window, int, 0644); MODULE_PARM_DESC(hystart_low_window, "lower bound cwnd for hybrid slow start"); +module_param(hystart_ack_delta, int, 0644); +MODULE_PARM_DESC(hystart_ack_delta, "spacing between ack's indicating train (msecs)"); /* BIC TCP Parameters */ struct bictcp { @@ -343,7 +346,7 @@ static void hystart_update(struct sock * /* first detection parameter - ack-train detection */ if ((s32)(curr_jiffies - ca->last_jiffies) <= - msecs_to_jiffies(2)) { + msecs_to_jiffies(hystart_ack_delta)) { ca->last_jiffies = curr_jiffies; if ((s32) (curr_jiffies - ca->round_start) > ca->delay_min >> 4)