A small computer on a smart card has 4 page frames. At the first clock tick, the R bits are 1000 (page 0 is 1 and the rest are 0). At subsequent ticks, the values are 0110, 0101, 1010, 1101, 0101, 0011, and 1100. If the aging algorithm is used with a 16-bit counter, give the values of the four counters after the last tick. If page fault occurs, which page should be swapped out

Answer and Explanation:

Aging algorithm Aging algorithms are the NFU algorithm with modification to know the time of span and increment the page referenced. The ageing method sort customer invoices by date in four columns. By using the ageing algorithm, counters are shifted by 1 bit, and the R bit is added to the leftmost bit. The values of counters are

Page 0:  01101110

Page 1:   01001001

Page 2:  00110111

Page 3:  10001011

The system clock is 2ns and interval is 2ms for that one bit per interval is the ability to analyze the references in a tick. Counters have a finite number and have two pages, where counter value 0 have two pages. The page fault appears, and pick just one of them randomly.