Origin 2000
•Intellectual
descendant of Stanford DASH
•Two
processors per node
•Caches
use MESI protocol
•Directory
has 7 states:
–Stable:
unowned, shared, exclusive (cl/dirty in $)
–Busy: Processor not ready to handle new requests to block, read,
readex, uncached
•Generally
O2000 follows protocols discussed
•Proves
basic ideas actually apply
•Shows
that simplifying assumptions must be revisited to get a system
built and deployed