The present invention relates to an improved microprocessor having a
memory system with several caches that can be operated to provide virtual
memory. Among the caches included in the microprocessor are conventional
caches that store data and instructions to be utilized by the processes
being performed by the microprocessor, and that are typically arranged in
a cache hierarchy, as well as one or more translation lookaside buffer
(TLB) caches that store a limited number of virtual page translations.
The improved microprocessor also has an additional cache that serves to
store a virtual hash page table (VHPT) that is accessed when TLB misses
occur. The introduction of this VHPT cache eliminates or at least reduces
the need for the microprocessor to look for information within the caches
of the cache hierarchy or in other memory (e.g., main memory) outside of
the microprocessor when TLB misses occur, and consequently enhances
microprocessor speed.