Will a graph with no cycles have a deadlock explain?
If a resource-allocation graph contains no cycles, then the system is not deadlocked.
Does presence of cycle in a resource allocation graph necessary creates deadlock?
In a Resource Allocation Graph where all the resources are NOT single instance, If a cycle is being formed, then system may be in a deadlock state. If no cycle is being formed, then system is not in a deadlock state. Presence of a cycle is a necessary but not a sufficient condition for the occurrence of deadlock.
What does it mean if the resource allocation graph contains a cycle and what if it not have a cycle?
In summary, if a resource-allocation graph does not have a cycle, then the system is not in a deadlocked state. If there is a cycle, then the system may or may not be in a deadlocked state. (which are currently blocked) to continue.
What is a cycle in a resource allocation graph?
A cycle in a Resource Allocation Graph suggests that there might be circular wait in the system, i.e. deadlock. However, this may happen without deadlock being present.
What is wait-for graph for deadlock detection?
A wait-for graph in computer science is a directed graph used for deadlock detection in operating systems and relational database systems. The possibility of a deadlock is implied by graph cycles in the conjunctive case, and by knots in the disjunctive case.
How is deadlock detected by Wait-for graph?
Wait-for-graph is one of the methods for detecting the deadlock situation. This method is suitable for smaller databases. In this method, a graph is drawn based on the transaction and their lock on the resource. If the graph created has a closed-loop or a cycle, then there is a deadlock.
How resource allocation graph can be used for deadlock detection?
If a cycle is being formed in a Resource allocation graph where all the resources have the single instance then the system is deadlocked. In Case of Resource allocation graph with multi-instanced resource types, Cycle is a necessary condition of deadlock but not the sufficient condition.
Does cycle mean deadlock?
If there is a cycle in the graph and each resource has only one instance, then there is deadlock. In this case, a cycle is a necessary and sufficient condition for deadlock. If there is a cycle in the graph, and each resource has more than one instance, there may or may not be deadlock.
How a resource allocation graph can be used to show the presence of a deadlock?
Which of the following is false if the resource allocation graph contains no cycles?
If there are no cycles in resource allocation graph then there is no deadlock. 2. If there is only one instance per resource type and resource allocation graph has a cycle then there is a deadlock.
What is a deadlock in resource-allocation?
Deadlock: A set of blocked processes each waiting for an event. (e.g. a resource to become available) that only another process.
What is the difference between wait-for graph and resource allocation graph?
A wait-for graph in computer science is a directed graph used for deadlock detection in operating systems and relational database systems. The wait-for-graph scheme is not applicable to a resource allocation system with multiple instances of each resource type.