History of Coherence 

1965 - Multiprocessor buffer interrogation*

1970 - Relational DB

1973 - Compare and Swap (CS)

Late 1970s - Locks replaced by CS

1980s - Invalidation replaces Interrogation (Snoopy*)

2022 - Patent for CS in main memory. (CS & main memory)

2023 - Patent for Coherent Memory. (Relational & main memory)

2023 - Patent to identify memory that needs to be coherent. (1970 & 1973 & 2022)

202? - Coherence vanishes.

 

Relational main memory does not require coherence.

 It is Coherent Memory

Coherent Memory = Relational Memory = Shared Data = Relational Data

 

 * Uses an algorithm that is binomial and limits multi core to 4. 

 

 Different Algorithms for the Same Problem