The value of cache memory is the "hit ratio". If increasing cache size by 50% increases cache-hit from 95% to 99%, is worth it, as the 5% of cache-misses could

The value of cache memory is the "hit ratio". If increasing cache size by 50% increases cache-hit from 95% to 99%, is worth it, as the 5% of cache-misses could reduce CPU performance to one half.