reuse used recently in near future
- Temporal locality: recently referenced item
instruction: loop iteration
data: stack argument(scalar access)
- Spatial locality: nearby addresses (instruction more)
instruction: in sequence
data: array (vector access)
data hierarchy: use data efficiently by least memory hardware
Block size: raise spatial locality and and reduce comp,capacity(reload) misses but increase conflict misses and miss penalty Cache size: reduce capacity, conflict misses but hit time increase Replacement policy: change temporal locality