In operating systems (OS), managing resources efficiently is crucial to ensure smooth and reliable performance. Two critical concepts related to resource allocation are deadlock and starvation.

What is Deadlock?

Deadlock is a situation where two or more processes are stuck in a state where they are waiting for each other to release resources, resulting in a standstill. In a deadlock, none of the processes involved can proceed because they are each waiting on resources held by the others.

Examples of Deadlock:

1. Resource Allocation: Process A holds Resource 1 and waits for Resource 2 held by Process B, while Process B holds Resource 2 and waits for Resource 1.
2. Database Transactions: Transaction 1 locks Table A and waits for Table B, while Transaction 2 locks Table B and waits for Table A.

What is Starvation?

Starvation occurs when a process is perpetually denied the resources it needs to proceed because other processes continually acquire those resources first. Unlike deadlock, where processes are stuck waiting indefinitely, starvation results from unfair resource allocation that leaves some processes in a perpetual waiting state.

Examples of Starvation:

1. Priority Scheduling: A low-priority process might never get CPU time if higher-priority processes are continuously arriving.
2. Resource Allocation: A process requesting memory might be starved if higher-priority processes continually allocate the available memory.

Difference Between Deadlock and Starvation: 

Basis	Deadlock	Starvation
Definition	A situation where processes are unable to proceed because they are each waiting for resources held by others.	A condition where a process is perpetually denied resources due to continuous allocation to other processes.
Cause	Circular wait, where a cycle of dependencies occurs.	Unfair resource allocation or priority scheduling.
Impact	All involved processes are stuck and unable to progress.	Some processes are unable to gain necessary resources to proceed.
Detection	Can be detected using algorithms like the Banker's Algorithm or through resource allocation graphs.	Can be detected by observing processes that are waiting indefinitely despite resource availability.
Resolution	Requires intervention to break the cycle, such as resource preemption or killing processes.	Requires adjustments in scheduling policies or resource allocation strategies to ensure fairness.
Prevention Strategies	Implementing protocols like deadlock prevention or avoidance algorithms.	Using algorithms to ensure all processes get a fair chance to access resources, such as aging or priority adjustments.