Set-Associative Cache

Set-Associative caches are a family of cache placement policies (how do we organize things inside of a cache?) that think of a cache as an ordered array of sets, each one containing an unordered sequence of entries (or cache lines). As such, they generalize over both direct mapped caches (n sets, 1 entry/set) and fully associative caches (1 set, n entries/set), while encompassing tradeoffs between the two types (k sets, n/k entries/set).

This is notably different from the independent notation of cache replacement policies, which ask the question: "when we need to, how do we choose which cache entry to replace with a new one?". For the purposes of this visualization, our cache replacement policy will be to evict the least recently used (LRU) cache line, but other possible options for eviction can be found here.