Bandwidth of a cache directory by slicing the cache directory into two smaller cache directories and replicating snooping logic for each sliced cache directory

摘要

A cache, system and method for improving the snoop bandwidth of a cache directory. A cache directory may be sliced into two smaller cache directories each with its own snooping logic. By having two cache directories that can be accessed simultaneously, the bandwidth can be essentially doubled. Furthermore, a “frequency matcher” may shift the cycle speed to a lower speed upon receiving snoop addresses from the interconnect thereby slowing down the rate at which requests are transmitted to the dispatch pipelines. Each dispatch pipeline is coupled to a sliced cache directory and is configured to search the cache directory to determine if data at the received addresses is stored in the cache memory. As a result of slowing down the rate at which requests are transmitted to the dispatch pipelines and accessing the two sliced cache directories simultaneously, the bandwidth or throughput of the cache directory may be improved.