SYNOPSIS

latency [ options ]

DESCRIPTION

latency is part of the Xenomai test suite. It is a timer latency benchmark program. The system must run a suitable Xenomai enabled kernel with the respective module (xeno_timerbench).

OPTIONS

latency accepts the following options:

-h

print histograms of min, avg, max latencies

-g <file>

dump histogram to <file> in a format easily readable with gnuplot. An example script for gnuplot may be found in scripts/histo.gp in Xenomai sources distribution

-s

print statistics of min, avg, max latencies

-H <histogram-size>

default = 200, increase if your last bucket is full

-B <bucket-size>

default = 1000ns, decrease for more resolution

-p <period_us>

sampling period

-l <data-lines per header>

default=21, 0 to suppress headers

-T <test_duration_seconds>

default=0, so ^C to end

-q

suppresses RTD, RTH lines if -T is used

-D <testing_device_no>

number of testing device, default=0

-t <test_mode>

0=user task (default), 1=kernel task, 2=timer IRQ

-f

freeze trace for each new max latency

-c <cpu>

pin measuring task down to given CPU

-P <priority>

task priority (test mode 0 and 1 only)

-b

break upon mode switch

AUTHOR

latency was written by Philippe Gerum. This man page was written by Roland Stigge.