Running ggd as a Real-time Process

1. Create or modify the file /etc/config/ggd.options and add -c cpunum to the file. cpunum is the number of a processor to be dedicated to GRIO. This causes the CPU to be marked isolated, restricted to running selected processes, and nonpreemptive. Processes using GRIO should mark their processes as real-time and runable only on CPU cpunum. The sysmp(2) reference page explains how to do this.

2. Restart the ggd daemon. See the section "Restarting the ggd Daemon" in this chapter for directions.

3. After ggd has been restarted, you can confirm that the CPU has been marked by giving this command (cpunum is 3 in this example):

   # mpadmin -s

   processors: 0 1 2 3 4 5 6 7

   unrestricted: 0 1 2 5 6 7

   isolated: 3

   restricted: 3

   preemptive: 0 1 2 4 5 6 7

   clock: 0

   fast clock: 0

4. To mark an additional CPU for real-time processes after ggd has been restarted, give these commands:

   # mpadmin -rcpunum2

   # mpadmin -Icpunum2

   # mpadmin -Ccpunum2