Basic OS Concepts

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Context Switch: Storing the state(registers,local variables etc) of the currently running process and restoring the state of the new process is called context switch.It is nothing but switching between two processes.This operation is performed by scheduler.

Starvation: It is a scenario in which a low priority process is waiting for a resource for a long time, which is acquired by the high priority process and is not released.Here the low priority process is starving for the resource.

Aging:  It is a mechanism to solve the problem of starvation. Whenever any process is waiting for a long time for a resource, it will increase the priority of the resource,so that it gets the resource it is starving for.

DeadLock: It is a scenario in which two processes are waiting for a resource which is present in the other process.For example, Process P1 wants a resource R1 which is acquired by Process P2,whereas the Process P2 requires a resource R2 which is acquired by P1.So both cannot perform any operation,and the system hangs.



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