Q2. Determine whether the given resource allocation graphs contains deadlock
or not? If the graph contain deadlock show the processes involved in the
deadlock and if there is no deadlock in the graph than explain why the system is
not in the deadlock state
[6 marks]
I.
P3
22
Answers
Answer: Ra and Rb are resource sets and every dot inside of them are resources. Circles are processes. An arrow from process to a resource set means that process is requesting a resource from that set. An arrow from resource set to process means that process owns a resource from that resource set.
I want to have your opinions on this, because the lecturer's answer is conflicting with mine. Lecturer says there is a deadlock here. But my answer was, since Py and Pz are not requesting a resource, they will simply continue their execution and terminate, releasing their resources. Then Px and Pw can obtain their requested resources and keep executing. It is obvious there is a cycle in this graph as Px-Pw but this doesn't conclude us to a deadlock. Thus I can't see a way to make "there is a deadlock here"conclusion.