Deadlock occurs when each process holds a resource and wait for other resource held by any other process. Necessary conditions for deadlock to occur are Mutual Exclusion, Hold and Wait, No Preemption and Circular Wait. In this no process holding one resource and waiting for another get executed. For example, in the below diagram, Process 1 is holding Resource 1 and waiting for resource 2 which is acquired by process 2, and process 2 is waiting for resource 1. Hence both process 1 and process 2 are in deadlock.
Starvation is the problem that occurs when high priority processes keep executing and low priority processes get blocked for indefinite time. In heavily loaded computer system, a steady stream of higher-priority processes can prevent a low-priority process from ever getting the CPU. In starvation resources are continuously utilized by high priority processes. Problem of starvation can be resolved using Aging. In Aging priority of long waiting processes is gradually increased.
