Re: [PATCH v4 3/3] tcp: early retransmit: delayed fast retransmit
From: Neal Cardwell <ncardwell@google.com>
Date: 2012-05-03 00:15:20
On Wed, May 2, 2012 at 7:30 PM, Yuchung Cheng [off-list ref] wrote:
Implementing the advanced early retransmit (sysctl_tcp_early_retrans==2). Delays the fast retransmit by an interval of RTT/4. We borrow the RTO timer to implement the delay. If we receive another ACK or send a new packet, the timer is cancelled and restored to original RTO value offset by time elapsed. When the delayed-ER timer fires, we enter fast recovery and perform fast retransmit. Signed-off-by: Yuchung Cheng <redacted> --- ChangeLog in v2: - Set sysctl_tcp_early_retrans default to 2 ChangeLog in v3: - use separate u8 for early retrans stats in tcp_sock - disable ER if detects any reordering ChangeLog in v4: - move disabling ER code on reordering into part2
Acked-by: Neal Cardwell <ncardwell@google.com> neal