Editing MESI protocol (section)

== Disadvantage of MESI ==
In case continuous read and write operations are performed by various caches on a particular block, the data has to be flushed to the bus every time. Thus, the main memory will pull this on every flush and remain in a clean state. But this is not a requirement and is just an additional overhead caused by using MESI. This challenge was overcome by the [[MOESI protocol]].<ref>{{Cite web|url=http://www.cs.wustl.edu/~roger/569M/24593.pdf|title=Memory System (Memory Coherency and Protocol)|date=September 2006|publisher=AMD64 Technology}}</ref>

In case of S (Shared State), multiple snoopers may response with FlushOpt with the same data (see the example above). The F state in [[MESIF protocol|MESIF]] addresses this redundancy.