PPT Slide
Deadlock Prevention
- Involves breaking one of the four necessary conditions:
1. Allow preemption. Not always possible (how to preempt a printer, tape drive, or other non-shareable resource?)
2. Avoid mutual exclusion: Create virtual instances, where each processes has the illusion of mutex (again, not always possible).
3. Avoid “Hold & Wait”: One technique is to force processes to acquire all their resources at one time, preventing any future waiting. This is inefficient and a process may not always know what it’s future needs are.