TIME_WAIT

    I still think that it is better to keep the connection open for a small
    amount of time as the server socket will go into TIME_WAIT state when
    it is closed and then can't be reused before about 240 seconds
    (recommended timeout accorsing to Simon)
    
This not just Simon's recommendation.  This is a MUST (i.e., mandatory)
requirement of RFC1122 (section 4.2.2.13).

And, to clarify: what cannot be reused is the memory allocated to the
connection state record; all other resources are reusable.  However, in
most BSD-based systems, this memory usage can be significant (one
mbuf).

-Jeff