quiz2-OS

Because of virtual memory, the memory can be shared among

• processes

• threads

• instructions

• none of the mentioned

Effective access time is directly proportional to

• page-fault rate

• hit ratio

• page table access time

• none of the mentioned

Which one of the following is the address generated by CPU?

• physical address

• absolute address

• logical address

• none of the mentioned

Which algorithm chooses the page that has not been used for the longest period of time whenever the page required to be replaced?

• first in first out algorithm

• counting based page replacement algorithm

• additional reference bit algorithm

• least recently used algorithm

A process is thrashing if

• it is spending less time paging than executing

• it is spending more time paging than executing

• swapping can not take place

• page fault occurs

The time for the disk arm to move the heads to the cylinder containing the desired sector is called

• disk time

• seek time

• arm time

• sector time

Which algorithm of disk scheduling selects the request with the least seek time from the current head positions?

• SSTF scheduling

• FCFS scheduling

• SCAN scheduling

• LOOK scheduling

A swap space can reside in

• Cache

• Separate disk partition

• RAM

• None of the mentioned

Run time mapping from virtual to physical address is done by

• Memory management unit

• CPU

• PCI

• None of the mentioned

The operating system is responsible for?

• disk initialization

• booting from disk

• bad-block recovery

• all of the mentioned