MOSI protocol

The MOSI protocol is an extension of the basic MSI cache coherency protocol. It adds the Owned state, which indicates that the current processor owns this block, and will service requests from other processors for the block.

For any given pair of caches, the permitted states of a given cache line are as follows:

	M	O	S	I
M	N	N	N	Y
O	N	N	Y	Y
S	N	Y	Y	Y
I	Y	Y	Y	Y

See also

• Coherence protocol
• MSI protocol
• MESI protocol
• MOESI protocol