TCP stack throughput

Ulf Wiger (AL/EAB) <>
Tue Jul 5 21:53:34 CEST 2005


Corrado Santoro wrote:
>
> Have you tried "netstat"? You should note many sockets in the 
> FIN_WAIT 
> state. So probably the delay you experience is due to the fact that 
> there are no more sockets available (in the kernel socket 
> table), so you 
> must wait until sockets in FIN_WAIT are finally flushed.

You're absolutely right, except my netstat lists it as TIME_WAIT.
This is described in the man page as:

     TIME_WAIT
           Wait after close for remote shutdown retransmission.

I found this page explaining the problem of sockets lingering in
TIME_WAIT, with examples of how to reduce the time on different
operating systems:

http://www.octetstring.com/support/issues/Tuning-TIMEWAIT.php

Unfortunately, I can't do this on my system, as I lack root privs. 
At least, I can inspect it:

> /usr/sbin/ndd -get /dev/tcp tcp_time_wait_interval 
240000

/Uffe



More information about the erlang-questions mailing list