PPT Slide
Deadlock
- Situation where two or more processes are each waiting for a resource that another process in the group holds.
- Figure 8.9 illustrates deadlock; this is an example of a resource allocation graph:
- Arrows FROM process TO resource indicate a resource request.
- Arrows TO process FROM resource indicate an allocated resource.
- In this case, a cycle exists with no other resource instances, thus deadlock exists!
- Similar deadlock exists with 2-process Send()/Receive() cycle & 4-process cycle.