Consider the following statements about user level threads and kernel level threads. Which one of the following statement is FALSE?

The Process Control Block is:

The time required to create a new thread in an existing process is

The register context and stacks of a thread are deallocated when the thread

A process stack does not contain

Consider a system having ‘m’ resources of the same type. These resources are shared by three processes P1, P2and P3 which have peak demands of 2, 5 and 7 resources respectively. For what value of ‘m’ deadlock will not occur?

Which of the following is NOT true of deadlock prevention and deadlock avoidance schemes?

An operating system implements a policy that requires a process to release all resources before making a request for another resource. Select the TRUE statement from the following:

What is the minimum number of resources required to ensure that deadlock will never occur, if there are currently three processes P1, P2 and P3 running in a system whose maximum demand for the resources of same type are 3, 4, and 5 respectively.

Let m[0]…m[4] be mutexes (binary semaphores) and P[0] …. P[4] be processes.

Suppose each process P[i] executes the following:

  wait (m[i]); wait(m[(i+1) mode 4]); ------ release (m[i]); release (m[(i+1)mod 4]);

This could cause:

Which of the following scheduling algorithms is non-preemptive?

An operating system uses shortest remaining time first scheduling algorithm for pre-emptive scheduling of processes. Consider the following set of processes with their arrival times and CPU burst times (in milliseconds):

The average waiting time (in milliseconds) of the processes is _________.

Four jobs to be executed on a single processor system arrive at time 0 in the order A, B, C, D. Their burst CPU time requirements are 4, 1, 8, 1 time units respectively. The completion time of A under round robin scheduling with time slice of one time unit is

An operating system uses Shortest Remaining Time first (SRT) process scheduling algorithm. Consider the arrival times and execution times for the following processes:

What is the total waiting time for process P2?

The most optimal scheduling algorithm is :

Assume every process requires 3 seconds of service time in a system with single processor. If new processes are arriving at the rate of 10 processes per minute, then estimate the fraction of time CPU is busy in system?

What is interprocess communication?

A counting semaphore was initialised to 7. Then 20 P (wait) operations and x V (signal) operations were completed on this semaphore. If the final value of semaphore is 5, then the value x will be

A process executes the code

fork();

fork();

fork();

The total number of child processes created is

A critical region