receiver was not sending an immediate ack with delayed acks turned on
when the input buffer is drained, preventing the transmitter from
restarting immediately.
Propogate the TCP_NODELAY option to accept()ed sockets. (Helps tbench and
is a good idea anyway).
Some cleanup. Identify additonal issues in comments.
MFC after: 1 day
to be followed by nfsnodehashtbl, so bzeroing callouts beyond the end of
tcp_syncache soon caused a null pointer panic when nfsnodehashtbl was
accessed.
