Page Replacement Algorithms

Consider the following sequence of page references:

1 2 3 4 4 2 1 4 1 3 4

Determine how many page faults will occur for the "Optimal" algorithms, assuming there are only "2 frames".

• 10 page faults

• 8 page faults

• 6 page faults

• 4 page faults

Consider the following sequence of page references:

1 2 3 4 4 2 1 4 1 3 4

Determine how many page faults will occur for the "FIFO" algorithms, assuming there are only "2 frames".

• 9 page faults

• 7 page faults

• 5 page faults

• 3 page faults

Which of the following page replacement algorithms suffer from “Belady’s anomaly?

• Second Chance

• FIFO

• LRU

• Optimal

Which of the algorithms requires future knowledge of the reference string?

• FIFO

• Random

• LRU

• Optimal

Second chance algorithm is actually a FIFO replacement algorithm with a small modification that causes it to be similar to least recently used

• True

• False

Consider the following sequence of page references:

7 0 1 2 0 3 0 4 2 3 0

Determine how many page faults will occur for the "FIFO" algorithms, assuming there are only "3 frames".

• 12 page faults

• 10 page faults

• 8 page faults

• 6 page faults

Consider the following sequence of page references:

7 0 1 2 0 3 0 4 2 3 0

Determine how many page faults will occur for the "LRU" algorithms, assuming there are only "3 frames".

• 10 page faults

• 9 page faults

• 8 page faults

• 7 page faults

A process refers to 5 pages, A, B, C, D, E in the order :

A B C D A B E A B C D E

If the page replacement algorithm is FIFO, the number of page transfers with an empty internal store of 3 frames is?

• 10 page faults

• 9 page faults

• 8 page faults

• 7 page faults

Users _______ that their processes are running on a paged system.

• are aware

• are not aware

• maybe aware

• None of the above answers

The aim of creating page replacement algorithms is to ____________

• replace pages faster

• increase the page fault rate

• decrease the page fault rate

• to allocate multiple pages to processes