A two-level memory system has eight virtual pages on a disk to be mapped into four page frames {PFs) in the main memory. A certain program generated the following page trace:
(a) Show the successive virtual pages residing in the four page frames with respect to the above page trace using the LRU replacement policy. Compute the hit ratio in the main memory. assume the PFs are initially empty.
(b) Repeat part (a) for the circular FIFO page replacement policy. Compute the hit ratio in the main memory
(c) Compare the hit ratio in parts (a) and (b) and comment on the effectiveness of using the circular FIFO policy to approximate the LRU policy with respect to dais particular page trace.