Research On Distributed Hybrid Real-Time Database Transactions

With the rapid development of computer network and database technology, Real-Time Databases Manage System(RTDBMS) application are widely used in various application fields, such as science research industry military affairs communication and finance The high performance of RTDBMS is brought forward in new application fields. In the real world , there are lots of hybrid real-time transactions, which are compounds of hard real-time transaction and non-real-time transaction, fixed real-time transaction and non-real-time transaction, soft real-time transaction and non-real-time transaction, the paper suggests that the hybrid real-time transactions be divided into genuine real-time(hard real-time or fixed real-time or soft real-time) and non-real-time parts which are differently disposed, it makes the system meet data integrity constraints and timing constrains, so improves system efficiency In this paper, firstly, traditional real-time database system and real-time transaction scheduling and real-time concurrency control protocol are studied. It discusses real-time database system model, real-time transaction property and class, transaction scheduling based on value, transaction scheduling based on accessing, dynamic overload managing; concurrence control based lock, optimistic concurrence control, multi-version concurrence control etc Next, a transaction including genuine real-time (hard real-time, fixed real-time, soft real-time) and non-real-time is proposed, Hybrid real-time database system model is given It discusses and analyzes detailedly transaction value model of hybrid real-time transaction, studies hybrid real-time transaction scheduling and concurrence control based on traditional real-time transaction scheduling and concurrence control Furthermore, it studies distributed hybrid real-time transaction model, distributed hybrid real-time database system framework., distributed hybrid real-time transaction value model, admission control mechanism for distributed hybrid real-time transaction, transaction submit protocol and concurrence control protocol for distributed hybrid real-time transaction. It emphasizes on researching admission control mechanism for distributed hybrid real-time transaction It considers both the executing requirement and the value of distributed hybrid real-time transaction, In order to maximize system profit, it reserves system resources and controls effectively system load, by reducing the number of transactions being accepted for execution but not able to come to its deadline. 2PL-HV, OPT-HV-Sacrifice concurrence control are analyzed on distributed hybrid real-time transaction property...