tcp: do not aggressively quick ack after ECN events
authorEric Dumazet <edumazet@google.com>
Mon, 21 May 2018 22:08:57 +0000 (15:08 -0700)
committerDavid S. Miller <davem@davemloft.net>
Tue, 22 May 2018 19:43:15 +0000 (15:43 -0400)
commit522040ea5fdd1c33bbf75e1d7c7c0422b96a94ef
treed03e8652fbb29e5b292da90865bfc3f591fa87c7
parent9a9c9b51e54618861420093ae6e9b50a961914c5
tcp: do not aggressively quick ack after ECN events

ECN signals currently forces TCP to enter quickack mode for
up to 16 (TCP_MAX_QUICKACKS) following incoming packets.

We believe this is not needed, and only sending one immediate ack
for the current packet should be enough.

This should reduce the extra load noticed in DCTCP environments,
after congestion events.

This is part 2 of our effort to reduce pure ACK packets.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Soheil Hassas Yeganeh <soheil@google.com>
Acked-by: Yuchung Cheng <ycheng@google.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
net/ipv4/tcp_input.c