Flexible techniques for associating cache memories with processors and main memory

Abstract

Caches are associated with processors, such multiple caches may be associated with multiple processors. This association may be different for different main memory address ranges. The techniques of the invention are flexible, as a system designer can choose how the caches are associated with processors and main memory banks, and the association between caches, processors, and main memory banks may be changed while the multiprocessor system is operating. Cache coherence may or may not be maintained. An effective address in an illustrative embodiment comprises an interest group and an associated address. The interest group is an index into a cache vector table and an entry into the cache vector table and the associated address is used to select one of the caches. This selection can be pseudo-random. Alternatively, in some applications, the cache vector table may be eliminated, with the interest group directly encoding the subset of caches to use.