OSADL Manpage

mklatency

Section: (8)
Updated: 0.1
Index

NAME

mklatency - Artificially create latency through a blocking driver

SYNTAX

mklatency

DESCRIPTION

The program mklatency uses the blocksys driver to artificially create a system latency for testing purposes. It may, for example, be used to make sure that the cyclictest tool is, in fact, able to determine a system latency should one occur (see example).

OPTIONS

(none)

FILES

blocksys.ko

EXAMPLES

The following commands to be entered from two separate root shells:

Shell #1:

cyclictest -a -t -n -p99

Shell #2:

modprobe blocksys
mklatency
tail /var/log/messages
[..] kernel: blocksys: CPU #0 will be blocked for 2000000 nops
[..] kernel: blocksys: CPU #0 blocked about 1270 us

Shell #1: The cyclictest should have detected the generated latency.