GATE Overflow Test Series | Operating Systems | Test 1 | Question: 10

Question

Which of the following is/are correct? (Mark all the appropriate choices)

• A. Switching the CPU to another process requires performing a state save of the current process and a state restore of a different process.
• B. Whenever an interrupt arrives, the CPU kills the currently executing process.
• C. A typical Operating System allows a process to create threads but not another process.
• D. Only the processes in Ready state are stored in the job queue.

Answer 1

Switching the CPU to another process requires performing a state save of the current process and a state restore of a different process. This task is know as a context switch.
 
  Whenever an interrupt arrives, the CPU must do a state-save of the currently running process, then switch into kernel mode to handle the interrupt, and then do a state-restore of the interrupted process.
 
  Processes may create other processes through appropriate system calls, such as fork or spawn. The process which does the creating is termed the parent of the other process, which is termed its child.
 
  All processes are stored in the job queue. And processes in the Ready state are placed in the ready queue.

Comments

All processes are stored in the Job queue.

Is that correct? Processes which are waiting to be loaded into the main memory are placed in the job queue. Once they are selected by long term scheduler, processes are put in ready queue and will be selected for execution by short term scheduler.