how does the home node know that the most up to date data is in P2?
Split_Personality_Computer
@gogogo It looks like memory is split up between the processors so P0 goes to read memory that originally resided in P1 but then it is P1's job to tell P0 that P2 actually has the most up-to-date version of what it is looking for (because P2 must've read & changed the value from P1).
So P0 requests the most up-to-date location from P1 because P1's directory has a list of who has what.
how does the home node know that the most up to date data is in P2?
@gogogo It looks like memory is split up between the processors so P0 goes to read memory that originally resided in P1 but then it is P1's job to tell P0 that P2 actually has the most up-to-date version of what it is looking for (because P2 must've read & changed the value from P1).
So P0 requests the most up-to-date location from P1 because P1's directory has a list of who has what.