(3) MOESI_CMP_directory is a two-level hierarchical directory-directory
protocol, which I believe is usable for both inter- and intra-chip
coherence. The Cadillac of coherence, if you will. I don't know what
MOESI_CMP_homedirectory is.
MOESI_CMP_homedirectory is a slight variation of MOESI_CMP_directory. The former stores on-chip directory state in L2 tags (hence maintains strict inclusion between an L2 block and its sharers). The latter uses a seperate structure (
i.e., shadow tags) to name on-chip sharers hence the L2 is non-inclusive w/ L1 sharers.