Question:
Cache access time
A single level cache has following specifications.
Access time = 2.5 ns
Line size = 64 bytes
Hit ratio = 0.95
Main memory uses a block transfer capability, and has first word (4 bytes) access time of 50 ns and access time for following words as 5 ns.
Compute the access time when there is a cache miss? Assume that the cache waits until the line has been fetched from main memory and then re-executes for a hit.
Will increasing the line size to 128 bytes, and a resulting increase in H (hit ratio) to .97, reduce the average memory access time?