关键词: 动态, 多粒度, 封锁, 事务截止期

Abstract: Multi-granularity locking mechanism improves the concurrency of the database system. But in real-time database, the traditional multi-granularity locking mechanism meets serious challenge for the real-time demand of its transaction processing. In this paper, considering multi-granularity locking mechanism and the transaction deadline, a dynamic multi-granularity locking mechanism based on transaction deadline is proposed. The transaction conflicts level are determined by transaction deadline, and when the conflicts reach or drop to a certain level, the locking granularity is adjusted accortding to current locking granularity. Through simulations, the expermental results show that this mechanism can not only reduce transaction confilicts, but also reduce the miss ratio and restart ratio of transaction, improve transaction concurrency and real-time.

Key words: dynamical, multi-granular, lock, transaction deadline