From aac46324e12a2bf2e9e0855ad6a287945e34ad39 Mon Sep 17 00:00:00 2001 From: stephen hemminger Date: Mon, 14 Mar 2011 07:52:14 +0000 Subject: [PATCH] tcp_cubic: make ack train delta value a parameter Make the spacing between ACK's that indicates a train a tuneable value like other hystart values. Signed-off-by: Stephen Hemminger Signed-off-by: David S. Miller --- net/ipv4/tcp_cubic.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/net/ipv4/tcp_cubic.c b/net/ipv4/tcp_cubic.c index 43bb34c9b8bf..66d3b00233ec 100644 --- a/net/ipv4/tcp_cubic.c +++ b/net/ipv4/tcp_cubic.c @@ -52,6 +52,7 @@ static int tcp_friendliness __read_mostly = 1; 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, "hyrbrid slow start detection mechanisms" " 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 *sk, u32 delay) /* 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)