Two computers have the same processor and main memory, but different cache designs.

Cache A: 128 sets, 2-way set associative, 32-byte blocks, and it uses write-through. Cache B: 256 sets, direct-mapped, 32-byte blocks, and it uses write-back. For both computers the read miss time is 10 times the cache-read hit time. For the write-through cache, writing a 32-bit word (into the cache AND through to main memory) takes 5 times as long as a cache hit. For the write-back cache a write-hit (writing to a word within a block that is in the cache) takes the same time as a read hit. Writing a 32-byte dirty block back to main memory, done when that dirty block is to be replaced with a new block, takes 10 times as long as a cache-read hit. The caches are unified, that is they contain both instructions and data.

A. ) It makes sense to use a Least Recently Used policy to decide what block to replace in Cache B. True of False? Why?