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.
has three forms of usage: as a server (-s), as a client (lat_udp localhost), and
as a shutdown (lat_udp -S localhost).
The reported time is in microseconds per round trip and includes the total
time, i.e., the context switching overhead is included.
Output format is like so
UDP latency using localhost: 650 microseconds
Funding for the development of
this tool was provided by Sun Microsystems Computer Corporation.