Computer Architecture
Faculty of Computer Science & Engineering - HCMUT
Chapter 5: Large and Fast:
Exploiting Memory Hierarchy
Binh Tran-Thanh
thanhbinh@hcmut.edu.vn
This chapter contents
▪Memory technology/ hierarchy
▪Cache and Virtual Memory
▪Memory performance
This chapter outcomes
Students who complete this course will be
able to
▪Explain the structure of a memory hierarchy.
▪Deeply understand how Memory, Cache, and
Virtual Memory work at the hardware level.
▪Estimate the performance of a memory
hierarchy as well as a system.
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Principle of Locality
▪Programs access a small proportion of their address
space at any time
▪Temporal locality
▪Items accessed recently are likely to be accessed again
soon
▪e.g., instructions in a loop, induction variables
▪Spatial locality
▪Items near those accessed recently are likely to be
accessed soon
▪E.g., sequential instruction access, array data
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Warm up
for (int i =0;i <MAX_SIZE;i ++){
Sum += Array[i];
}
▪Which variables/instructions exhibit
temporal locality?
▪Which variables /instructions exhibit spatial
locality?
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