Adaptive Locking Strategies in a Multi-node Data Sharing Environment

This paper describes some of the concurrency control 1” lgorithms used in RdMVMS RdbIVMS uses the ,fac.ilities provided by the VMS lock manager in order to perform locking among concurrent processes. The locking algorithms adapt to the contention among concurrent users by adjusting the number of locks required as well as the number of lock requests that are required per transaction. l‘his makes it possible to reduce the 1ockinR overhead considerably without sacrificing correctness or concurrency in a data sharing environment. These algorithms indicate that it is possible to achieve substantial improvements in certain situations.