Computer Organization

Problem 5.10.3:

Given the following 3 Tables:

Problem:		Virtual Addresses:
a.		4669, 2227, 13916, 34587, 48870, 12608, 49225
b.		12948, 49419, 46814, 13975, 40004, 12707, 52236
TLB
Valid:	Tag:	Physical Page Number
1	11	12
1	7	4
1	3	6
0	4	9
Page Table
Valid:	Physical Page or on Disk?
1	5
0	Disk
0	Disk
1	6
1	9
1	11
0	Disk
1	4
0	Disk
0	Disk
1	3
1	12

And the following background information:

As described in Section 5.4, virtual memory uses a page table to track the mapping of virtual addresses to physical addresses. This exercise shows how this table must be updated as addresses are accessed. The following table is a stream of virtual addresses as seen on a system. Assume 4 KB pages, a 4-entry fully associative TLB, and true LRU replacement. If pages must be brought in from disk, increment the next largest page number.

Question 5.10.3 States:

Show the final contents of the TLB if it is 2-way set associative. Also show the contents of the TLB if it is direct mapped. Discuss the importance of having a TLB to high performance. How would virtual memory accesses be handled if there were no TLB?