The chiplets have cache, which holds copies of memory. If a process has the line open in an exclusive state, e.g. locked, other chiplets cannot just get the lin

The chiplets have cache, which holds copies of memory. If a process has the line open in an exclusive state, e.g. locked, other chiplets cannot just get the line from memory, because it might be out of date. So they must go ask whoever holds the lock to flush & release. https://en.wikipedia.org/wiki/MESIF_protocol https://en.wikipedia.org/wiki/MESIF_protocol