Thread Priority
Many systems allow assignment of priority values to threads.
Each job in the ready pool has an associated priority value;the scheduler favors jobs with higher priority values.
- Assigned priorities reflect external preferences for particular users or tasks.
“All jobs are equal, but some jobs are more equal than others.”
- Example: running user interface threads (interactive) at higher priority improves the responsiveness of the system.
- Example: Unix nice system call to lower priority of a task.
- Example: Urgent tasks in a real-time process control system.