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 $Date$