ISSN:
1573-8787
Keywords:
Real-time
;
valid ratio
;
concurrency control
;
prescheduling
;
performance evaluation
Source:
Springer Online Journal Archives 1860-2000
Topics:
Computer Science
Notes:
Abstract A new priority management policy, aprescheduling policy, is proposed. This policy can be applied on any conventional concurrency control protocol to schedule a real-time transaction. Costly preemption is avoided by the prescheduling policy, and parsing dataset of a transaction is not needed. Three widely used conventional concurrency control protocols (dynamic two-phase locking, basic timestamp ordering, and optimistic) are incorporated with the prescheduling policy to form three real-time concurrency control protocols. Performance of the three protocols is evaluated from three different viewpoints: database management systems, protocols, and transaction. From a database management system viewpoint, we show the prescheduling policy can improve the performance of protocols by raising thevalid ratio and reducingrestart counts. In general, two-phase locking with the prescheduling policy performs the best in most cases and yields the best choice for concurrency control in a real-time application. Deciding factors that affect performance of each protocol are identified from protocol viewpoint. Some suggestions are given for writing a timely transaction from the aspect of transaction viewpoint.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF01974170
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