ptsematest(8)															     ptsematest(8)

NAME

       ptsematest - Start two threads and measure the latency of interprocess communication with POSIX mutex.

SYNTAX

       ptsematest [-a|-a PROC] [-b USEC] [-d DIST] [-i INTV] [-l loops] [-p PRIO] [-t|-t NUM]

DESCRIPTION

       The  program  ptsematest  starts two threads that are synchronized via pthread_mutex_unlock()/pthread_mutex_lock() and measures the latency
       between releasing and getting the lock.

OPTIONS

       -a, --affinity[=PROC]
	      Run on procesor number PROC. If PROC is not specified, run on current processor.

       -b, --breaktrace=USEC
	      Send break trace command when latency > USEC. This is a debugging option to control the latency tracer in  the  realtime	preemption
	      patch.  It is useful to track down unexpected large latencies of a system.

       -d, --distance=DIST
	      Set the distance of thread intervals in microseconds (default is 500 us). When  cylictest is called with the -t option and more than
	      one thread is created, then this distance value is added to the interval of the threads: Interval(thread N) = Interval(thread N-1) +
	      DIST

       -i, --interval=INTV
	      Set  the	base  interval of the thread(s) in microseconds (default is 1000 us). This sets the interval of the first thread. See also
	      -d.

       -l, --loops=LOOPS
	      Set the number of loops. The default is 0 (endless). This option is useful for automated tests with a given number of  test  cycles.
	      ptsematest is stopped once the number of timer intervals has been reached.

       -p, --prio=PRIO
	      Set the priority of the process.

       -t, --threads[=NUM]
	      Set  the number of test threads (default is 1, if this option is not given). If NUM is specified, create NUM test threads. If NUM is
	      not specifed, NUM is set to the number of available CPUs.

EXAMPLES

       The following example was running on a 4-way processor:

       # ptsematest -a -t -p99 -i100 -d25 -l1000000
       #0: ID8672, P99, CPU0, I100; #1: ID8673, P99, CPU0, Cycles 1000000
       #2: ID8674, P98, CPU1, I125; #3: ID8675, P98, CPU1, Cycles 811035
       #4: ID8676, P97, CPU2, I150; #5: ID8677, P97, CPU2, Cycles 668130
       #6: ID8678, P96, CPU3, I175; #7: ID8679, P96, CPU3, Cycles 589423
       #1 -> #0, Min	1, Cur	  1, Avg    2, Max   11
       #3 -> #2, Min	1, Cur	  2, Avg    2, Max   13
       #5 -> #4, Min	1, Cur	  4, Avg    3, Max   12
       #7 -> #6, Min	1, Cur	  4, Avg    2, Max   12

AUTHORS

       Carsten Emde <C.Emde@osadl.org>

SEE ALSO

       pthread_mutex_lock(3p), pthread_mutex_unlock(3p)

									0.1							     ptsematest(8)