Design of Concurrency Controls for Transaction Processing Systems.
Abstract
A complete transaction processing system was developed for Cm*, a distributed multi-microprocessor. This system used a concurrency control in which all functions required by the paradigm were available, and the concurrency control used a policy module implementing a number of policies, any of which could be chosen at run-time. The record manager of this system supported a simple relational view of the database, with one or more B-tree indexes for each relation. The record manager was replicated, and copies of versions of shared data objects were cached. The usefulness of the design framework was illustrated by the fact that the record manager, the most complex subsystem, was earlier developed on a completely different centralized system, and required only minor modifications to be used in this system. Experiments were performed with varying numbers of processors, and with various policies. For this system, the effect of waiting due to locking proved to be negligible, and so locking policies generally gave the best performance. This result may not apply to other systems, though: as an example of one of many possible differences, in this system individual processors were not multiprogrammed. However, using a concurrency control policy module, it is easy to investigate many different concurrency controls on any system, as demonstrated by these experiments.
Document Details
- Document Type
- Technical Report
- Publication Date
- Apr 02, 1982
- Accession Number
- ADA121515
Entities
People
- John T. Robinson
Organizations
- Carnegie Mellon University