Cache Coherency, The Goal
A multiprocessor memory system is coherent if for every location there exists a serial order for the operations on that location consistent with the results of the execution such that ...
- The subsequence of operations issued by any processor are in the order issued
- The value returned by each read is the value written by the last write in serial order
Implied property of coherency ...
Write Serialization -- all writes to a location are
seen in the same order by all processes