NAME

       lat_tcp - measure interprocess communication latency via TCP/IP

SYNOPSIS

       lat_tcp -s
       lat_tcp [ -m <message size> ] [ -P <parallelism> ] [ -W <warmups> ] [ -N <repetitions> ] hostname
       lat_tcp -S hostname

DESCRIPTION

       lat_tcp  is  a  client/server  program that measures interprocess communication latencies.  The benchmark
       passes a message back and forth between the two processes (this sort of benchmark is frequently  referred
       to as a ``hot potato'' benchmark).  No other work is done in the processes.

       lat_tcp  has  three  forms of usage: as a server (-s), as a client (lat_tcp localhost), and as a shutdown
       (lat_tcp -S localhost).

OUTPUT

       The reported time is in microseconds per round trip and  includes  the  total  time,  i.e.,  the  context
       switching overhead is includeded.  Output format is like so

       TCP latency using localhost: 700 microseconds

ACKNOWLEDGEMENT

       Funding for the development of this tool was provided by Sun Microsystems Computer Corporation.

SEE ALSO

       lmbench(8), lat_fcntl(8), lat_fifo(8), lat_tcp(8), lat_udp(8), lat_unix(8).

AUTHOR

       Carl Staelin and Larry McVoy

       Comments, suggestions, and bug reports are always welcome.

(c)1994 Larry McVoy                                  $Date$                                           LAT_TCP(8)