problem 1)a) prepare a detailed note on dual mode of operation.

b) What do you mean by a system call? List out various UNIX system calls related to file management.

c) prepare down the sequence of steps in a typical system booting.

d) What is a Process Control Block? Describe each field in the PCB.

problem 2)a) Describe the Inter_process Communication using mailboxes.

b) What are the benefits of Multithreading? prepare a detailed note on thread scheduling.

c) describe the function of dispatcher? Describe the method of predicting the next CPU burst time in case of SJF process scheduling algorithm.

d) On a system using round_robin (RR) scheduling, let ‘s’ represents the time needed to perform a process switch, ‘q’ represent the RR time quantum, and ‘r’ represent the average time a process runs before blocking on I/O. Give a formula for CPU efficiency given the following:

i) q>r

ii) s

problem 3)a) What do you mean by race condition of concurrent access ? Describe with suitable ex.

b) Define the swap() instruction for process synchronization and give an algorithm that satisfies the mutual exclusion requirement of critical section problem using swap() instruction.

c) It is required to allocate a single resource among competing processes. Each process, when requesting an allocation of this resource, specifies the maximum time it plans to use the resource. State a monitor to allocate the resource on priority bases where priority is inversely proportional to the time of usage of the resource.

d) What are the synchronization methods used in Linux version 2.6 onwards.

e) prepare down the definition of semaphore operations that encounter no busy wait loops.