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- Writes cause invalidations or updates to be sent over the bus
- All caches ``snoop'' the bus for messages they need to act upon
Write Update
- Send a write message and the data over the bus
- Other caches update their copies
- Similar to write-through
Write Invalidate
- Send an invalidation message over the bus
- All other caches delete their copies
- Similar to write-back
Paul H J Kelly
Mon Dec 1 20:13:28 GMT 1997