For 10 points, identify these devices that store recently used bits of memory in order to
 speed up future access.
Some of these make use of the Illinois Protocol, which is one of many algorithms that make use of the
 four words "modified," "shared," "exclusive" and "invalid" in order to prevent the "false sharing" problem
 inherent in these devices when trying to maintain their coherency. When implementing the write-back ones
 of these, an extra dirty bit is needed to maintain them. They can be direct mapped or set-associative at
 times, which allows them to hold more types of data. These devices exploit both temporal locality and
 spatial locality. For 10 points, identify these devices that store recently used bits of memory in order to
 speed up future access.
Some of these make use of the Illinois Protocol, which is one of many algorithms that make use of the
 four words "modified," "shared," "exclusive" and "invalid" in order to prevent the "false sharing" problem
 inherent in these devices when trying to maintain their coherency.
{caches}