为了在系统故障时保证嵌入式实时数据库系统中数据的时间一致性、恢复时间的可预测性及减少恢复时间,提出了一种基于实时日志的故障恢复策略.该策略根据数据的不同特征将其划分成不同类别,对每类数据采用不同的日志记录策略以提高系统性能;使用非易失性存储器作为稳定存储器存储关键数据及其日志以获得更快的存取时间及存取时间的可预测性.性能测试结果表明,所提出的恢复策略在降低事务超截止期比例和减少故障恢复时间等方面具有较好的性能.
In order to guarantee the time consistency of data,the predictability of recovery time,and reduce the recovery time in system failures for embedded real-time database systems,this paper presents a crash recovery strategy based on real-time logs.With this strategy,we divide the data into different categories according to different characteristics,and employ different logging strategies for different data categories to improve the system performance.Besides,we store critical data and corresponding logs in non-volatile RAM for fast access time and the predictability of access time.Performance evaluation shows that the recovery strategy based on real-time logs has better performance in decreasing the percentage of transactions missing their deadlines and reducing crash recovery time.