This is the test of sched_setscheduler and gettimeofday described
in 

Finney, S.A., (2001b), Behavior Research Methods, Instruments,
and Computers, "Real-time data collection in Linux: A case study".

It is not well documented, but you ought to be able to figure it
out. Compile the binaries with makebinaries.sh, then execute runtests.sh 
(which assumes that 300 seconds is enough time for all the background 
processes to finish). Note that for maximum performance, tests must
run with root privileges.
