Pre-analysis locking

Abstract

Locking is considered as a means to achieve serializable schedules of concurrent transactions. Transactions are assumed to be predeclared such that a pre-analysis for locking becomes feasible to increase concurrency. A condition for safety is introduced which, based on a pre-analysis, allows the design of policies strictly dominating known policies such as 2-phase locking. The static case, in which the complete set of transactions is known in advance, and the online case, in which a transaction is known when it is started, are considered. It is shown that a policy strictly dominating 2-phase locking and some other interesting pre-analysis policies can also be applied in an online environment