Directories seem to be useless on a cpu with only 2 cores, as if two cores are using directories to communicate with each other they aren't using up the interconnect any less than they would with a broadcast scheme.
What is the number of cores for which implementing directories first becomes advantageous?
bpr
@carnegieigenrac, it is a good insight that low core counts do not benefit from directories. I gave the rule of thumb number for switching between buses (i.e. snooping) to directories in class on Friday.
Directories seem to be useless on a cpu with only 2 cores, as if two cores are using directories to communicate with each other they aren't using up the interconnect any less than they would with a broadcast scheme.
What is the number of cores for which implementing directories first becomes advantageous?
@carnegieigenrac, it is a good insight that low core counts do not benefit from directories. I gave the rule of thumb number for switching between buses (i.e. snooping) to directories in class on Friday.