Active processes are placed in an array called a run queue, or runqueue.
Processes are also removed from the run queue when they ask to sleep, are waiting on a resource to become available, or have been terminated.
In the Linux operating system (prior to kernel 2.6.23), each CPU in the system is given a run queue, which maintains both an active and expired array of processes.
The scheduler selects the next process from the active array with highest priority.
In UNIX or Linux, the sar command is used to check the run queue.