However, the releaser sends to the acquirer all the modifications that it thinks that the acquirer is interested in. The acquirer invalidates pages for which write notices were received but no modifications were included in the lock grant message. Single pair of messages between acquirer and releaser, only have overhead of piggybacks. Amount of data is smaller than for the update protocol. Reduced number of access misses.
Lazy protocols send fewer messages and less data than the eager protocols.
Lazy update sends fewer messages generally than lazy invalidate, which lazy invalidate protocol sends less data than lazy update. All five are multiple-writer protocols. Multiple processors can concurrently write to their own copy, with the separate modifications being merged in a later release. Processors acquire locks by sending a request to a statically assigned owner, who forwards the request to the current lock holder. Data is exchanged in the form of diffs.