Went backed and looked at the RFC. The problem was just a simple translation of table to C array (0 based). Added this to the TCP testing repository.
Subject: [PATCH] Problem observed by Xiaoliang (David) Wei: When snd_cwnd is smaller than 38 and the connection is in congestion avoidance phase (snd_cwnd > snd_ssthresh), the snd_cwnd seems to stop growing. The additive increase was confused because C array's are 0 based. Signed-off-by: Stephen Hemminger <[EMAIL PROTECTED]> --- net/ipv4/tcp_highspeed.c | 3 ++- 1 files changed, 2 insertions(+), 1 deletions(-) 121685b7b61c8faeb87e6c6f0c346b0fe1c46fd2 diff --git a/net/ipv4/tcp_highspeed.c b/net/ipv4/tcp_highspeed.c index b72fa55..ba7c63c 100644 --- a/net/ipv4/tcp_highspeed.c +++ b/net/ipv4/tcp_highspeed.c @@ -135,7 +135,8 @@ static void hstcp_cong_avoid(struct sock /* Do additive increase */ if (tp->snd_cwnd < tp->snd_cwnd_clamp) { - tp->snd_cwnd_cnt += ca->ai; + /* cwnd = cwnd + a(w) / cwnd */ + tp->snd_cwnd_cnt += ca->ai + 1; if (tp->snd_cwnd_cnt >= tp->snd_cwnd) { tp->snd_cwnd_cnt -= tp->snd_cwnd; tp->snd_cwnd++; -- 1.3.3 - To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html