1.0 Memory Hierarchies

• Modern machines have memory hierarchies consisting of layers of memories between a processor and a primary storage device like a disk.

• As you get closer to the processor, the memories get faster but also smaller. 

• The difference between size, latency and bandwidth of these various levels might be in the order of magnitudes.

• The hardware or the Operating system can take care of the managing these memory hierarchies for us. But using these memories optimally is hard.

• Our usual algorithmic design style does not take into consideration these different memory hierarchies. 

• If we intend our algorithms to be high performant and take advantage of these memory hierarchies, we need to consider Locality aware algorithmic design model. 

• In the next post, we will see how we can use a variation of the Von Neumann architecture to construct a basic machine model and take the next steps in learning how we can develop our Locality aware algorithmic design intuition.

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