Patent attributes
A technique for performing stream detection and prefetching within a cache memory simplifies stream detection and prefetching. A bit in a cache directory or cache entry indicates that a cache line has not been accessed since being prefetched and another bit indicates the direction of a stream associated with the cache line. A next cache line is prefetched when a previously prefetched cache line is accessed, so that the cache always attempts to prefetch one cache line ahead of accesses, in the direction of a detected stream. Stream detection is performed in response to load misses tracked in the load miss queue (LMQ). The LMQ stores an offset indicating a first miss at the offset within a cache line. A next miss to the line sets a direction bit based on the difference between the first and second offsets and causes prefetch of the next line for the stream.
