Integrated concurrency-coherency controls for multisystem data sharing

The authors propose an integrated control mechanism and analyze the performance gain due to its use. An extension to the data sharing system structure is examined in which a shared intermediate memory is used for buffering and for early commit processing. Read-write-synchronization and write-serialization problems arise. The authors show how the integrated concurrency protocol can be used to overcome both problems. A queueing model is used to quantify the performance improvement. Although using intermediate memory as a buffering device produces a moderate performance benefit, the analysis shows that more substantial gains can be realized when this technique is combined with the use of an integrated concurrency-coherency control protocol.<>