Direct mapped : if each block has only one place it can appear in the cache, the cache is said to be direct mapped. The mapping is usually
Fully Associative : if a block can be placed anywhere in the cache, the cache is said to be fully associative.
: if a block can be
placed in a restricted set
of places in the cache, the cache is said to be
. A set is a group of blocks in the cache. A block is
first mapped onto a set,
the block can be placed
anywhere within that set.
The set is usually chosen by bit selection; that is,
The vast majority of processor caches today are direct mapped, two-way set associative, or four-way set associative.