
  Real Time Scheduler for Linux
  =============================

The Real Time scheduler patch gives you an option to choose to build a
kernel with MontaVista's real time scheduler in it.  If you don't choose
to enable the real time scheduler the kernel will be built the same as
if you had not installed the patch.

If you enable the real time scheduler, you may also choose a max
priority for real time tasks.  The available range is 99 to 2047.
Values outside this range are quietly moved to fall in the range.

In order to enable the real time scheduler you must use one of the
kernel configure tools to turn it on.  The question appears in the
processor options section of the configuration.

Currently the scheduler is supported on all UP and SMP machines.

Warning: The Real Time scheduler does not honor the "allowed_cpus"
member of the task_struct, thus it will not honor any attempt to define
cpu affinity.  The latest preemption patch uses cpu affinity to prevent
cpu switching during preemption.  This will not work with this scheduler
and may cause failures in kernels using preemption.  In addition TUX
is known to use cpu affinity.  It is believed that TUX will run with out
cpu affinity, but may have degraded performance.  It is also known that
some soft irq tasks may use cpu affinity to improve performance.  These
tasks will still work, however, the affinity will not happen.
