Pre-Analysis Locking: A Safe and Deadlock Free Locking Policy
نویسندگان
چکیده
A safe and deadlock free lock policy is introduced, called pre-analysis locking. Pre-analysis locking is based on an efficient geometric algorithm which inserts lock and unlock operations into the transactions. Pre-analysis locking is the first safe and deadlock free general locking policy which is not a variant of two-phase locking. It is an approach conceptually different from policies following the two-phase locking principle. In general, none of pre-analysis locking and two-phase locking dominates the other: there exist cases in which pre-analysis locking allows for more concurrency than any two-phase locking policy, but there are also cases in which a two-phase locking policy allows for more concurrency than pre-analysis locking.
منابع مشابه
A Pitfall in Fixation of Distal Humeral Fractures with Pre-Contoured Locking Compression Plate
Anatomically precontoured locking plates are intended to facilitate the fixation of articular fractures and particularly those associated with osteoporosis. Fractures of the distal humerus are relatively uncommon injuries where operative intervention can be exceptionally challenging. The distal humeral trochlea provides a very narrow anatomical window through which to pass a fixed-angle locking...
متن کاملStochastic Petri Net Analysis of Deadlock Detection Algorithms in Transaction Database Systems with Dynamic Locking
We develop stochastic Petri net (SPN) models to analyze the best time interval between two consecutive executions of periodic deadlock detection algorithms for two-phase locking database systems with dynamic locking. Our models can accurately estimate ‘wait time per lock conflict’ automatically and allow the best time interval to be determined as a function of workload intensities and database ...
متن کاملFlexible locking in SCOOP
The SCOOP model provides programmers with a simple extension of Eiffel that allows them to produce high-quality concurrent applications with little more effort than sequential ones. The model is simple yet powerful. Nevertheless, its access control policy is pessimistic: (1) all separate actual arguments of a feature call are locked, even if it is not necessary, and (2) at most one client objec...
متن کاملThe Transient Behavior of LC and Ring Oscillators under External Frequency Injection
In this work, time domain analysis is used to solve Adler’s equation in order to obtain the required time, for an oscillator under external injection, reaching the steady-state condition. Mathematical approach has been applied to fully describe the transient of frequency acquisition in injection-locked LC and Ring oscillators considering their time-varying nature. Then, the analysis is verifie...
متن کاملInvestigations in tree locking for compiled database applications
We report on initial experiments in tree locking schemes for compiled database applications. Such applications have a repository style of architecture in which a collection of software modules or subsystems operate on a common database in terms of a predefined set of transaction types, and are very often at the core of embedded systems. Since the tree locking protocol is deadlock free, it becom...
متن کامل