Parallel Computer Architecture

438

CHAPTER

6 Snoop-Based Multiprocessor Design

Sophisticated cache designs have also been proposed to solve the synonym coher-

ence problem in hardware (Goodman 1987). The idea is to use virtual addresses to

look up the cache on processor accesses but to put physical addresses on the bus for

other caches and devices to snoop. This requires mechanisms to be provided for the

following: (1) to look up the cache with the physical address if a lookup with the

virtual address fails (by which time the physical address is available) or if it is

detected that the block was brought into the cache by a synonym access; (2) to

ensure that the same physica ...