A Concrete Explanation of How a Cache Works Inside Your CPU

I explain how caches bridge the speed gap between fast processors and slower memory by leveraging the principle of locality. By treating the cache as a hardware-implemented hash table, we can understand how indexing, tag matching, and replacement policies determine performance. This breakdown covers everything from L1 and L2 cache organization to the mathematical trade-offs between hit latency and miss rates.
Being able to access a location immediately when given an address as a key means a cache is essentially a hash table implemented in hardware.