NAME

       pip_stress - test priority inheritance between processes

SYNOPSIS

       pip_stress

DESCRIPTION

       pip_stress  creates  a priority inversion using three processes and a priority inheritance
       mutex shared via shared memory.  All three processes are bound to run  on  the  same  cpu.
       The  process with the lowest priority holds a mutex and is prempted by the medium priority
       process that just runs an infinite loop.  The third  process  with  the  highest  priority
       tries  to  grab the mutex that is hold by the low prio process.  As a priority inheritance
       mutex is used the low priority process lends the high priority process' priority to unlock
       the mutex and so stops the medium priority process blocking the high priority one.

       pip_stress  doesn't  take  any  options  and  quits  as  soon as the priority inversion is
       resolved which should happen instantly.

AUTHOR

       pip_stress was written by John Kacur <jkacur@redhat.com>.

                                            2011-06-24                              pip_stress(8)