[SOLVED] VE370 Introduction to Computer Organization Homework 7

Description

1. For a 2-way set associative cache with a 32-bit address and write back mechanism, the partition of the 32 bits are as follows:

• • Offset: bit 6 to 0
  • Index: bit 11-7
  • What is the size of the cache?

Starting from power on, the following byte addresses were used to access the cache memory: 0, 4, 20, 136, 232, 164, 1024, 30, 140, 3100, 176, 2180

• What is the hit ratio?

• Show the final state of the cache, with each valid line represented as <index, tag, data>.

2.  In general, cache access time is proportional to its capacity. Assume that main memory accesses take 70 ns and that memory accesses are 36% of all instructions. The following table shows data for caches attached to each of two processors, P1 and P2.

• Assuming that the cache hit time determines the cycle times for P1 and P2, what are their respective clock rates?
• What is the AMAT for P1 and P2? AMAT (Average Memory Access Time) is defined as follows: AMAT = Hit time + Miss rate × Miss penalty
• Assuming a base CPI of 1.0 without any memory stalls, what is the actual CPI for P1 and P2? Which processor is faster?

3. Given the following byte addresses for memory access:

3, 180, 43, 3, 191, 89, 190, 14, 181, 44, 186, 252

• Show the final cache contents for a 3-way set associative cache with two-word blocks and a total size of 24 words. Use LRU replacement. For each reference identify the index bits, the tag bits, the offset bits, and if it is a hit or a miss. (20 points)

• Show the final cache contents for a fully associative cache with one-word blocks and a total size of 8 words. Use LRU replacement. For each reference identify the index bits, the tag bits, and if it is a hit or a miss.
• What is the miss rate for a fully associative cache with two-word blocks and a total size of 8 words, using LRU replacement? What is the miss rate using MRU (most recently used) replacement? Finally what is the best possible miss rate for this cache, given any replacement policy?