Unix Unix Memory Management - Technical Questions and Answers

11.

What is Fork swap?

12.

What is Expansion swap?

13.	How the Swapper works?
	Answer: The swapper is the only process that swaps the processes. The Swapper operates only in the Kernel mode and it does not uses System calls instead it uses internal Kernel functions for swapping. It is the archetype of all kernel process. Workspace Report errors ... Name : Email: View Answer

14.	What are the processes that are not bothered by the swapper? Give Reason.
	Answer: Zombie process: They do not take any up physical memory. Processes locked in memories that are updating the region of the process. Kernel swaps only the sleeping processes rather than the 'ready-to-run' processes, as they have the higher probability of being scheduled than the Sleeping processes. Workspace Report errors ... Name : Email: View Answer

15.

What are the requirements for a swapper to work?

16.	What are the criteria for choosing a process for swapping into memory from the swap device?
	Answer: The resident time of the processes in the swap device, the priority of the processes and the amount of time the processes had been swapped out. Workspace Report errors ... Name : Email: View Answer

17.	What are the criteria for choosing a process for swapping out of the memory to the swap device?
	Answer: The process's memory resident time, Priority of the process and The nice value. Workspace Report errors ... Name : Email: View Answer

18.

What do you mean by nice value?

19.	What are conditions on which deadlock can occur while swapping the processes?
	Answer: All processes in the main memory are asleep. All "ready-to-run" processes are swapped out. There is no space in the swap device for the new incoming process that are swapped out of the main memory. There is no space in the main memory for the new incoming process. Workspace Report errors ... Name : Email: View Answer

20.	What are conditions for a machine to support Demand Paging?
	Answer: Memory architecture must based on Pages, The machine must support the 'restartable' instructions. Workspace Report errors ... Name : Email: View Answer