面向分布式交互应用的事件完全序问题研究-《计算机技术与发展》

文章信息/Info

Title:: Research on Event Total Order Problem for Distributed Interactive Application

Author(s):: LI Yong; LU Wei; School of Information Engineering,Yanchang Teachers University,Yancheng 224002,China

Keywords:: distributed interactive application; event total order; periodic sampling; event sequence number

摘要:: 针对分布式交互应用(DIA)中的事件完全序问题进行研究,在DIA中,发生在两个不同节点上的事件如何排序,如何判断某个事件当前是否可以提交处理是非常关键的。由于网络传输时延的异构,不同DIA节点接收到事件的顺序是不一样的,DIA节点通常不能把事件的接收顺序作为处理顺序,也不能直接将已接收到的最小时间戳的事件作为当前需处理的事件,因为它无法判断是否有更小时间戳事件仍在网上传输,还未接收到。对此,提出了基于周期采样和事件序列号的DIA一致性控制方法(CCM_SE),CCM_SE包括周期采样机制和事件序列号机制两个方面。CCM_SE为了确保事件完全序一致性,不同节点上发生的事件通过时间戳来排序,并通过事件序列号机制来及时判断一个事件是否可以提交执行,以提高DIA事件的响应性。模拟仿真表明,CCM_SE可扩展性好,响应性好,并且能有效减少DIA中不一致现象的发生。

Abstract:: The event total order consistency problem in distributed interactive application (DIA) is studied. How to sort events occurred on two different nodes and how to determine whether an event may submit the current process is critical in DIA. Due to the heterogeneity of network transmission delay,the order of events received by different DIA nodes is different. DIA nodes generally cannot take the received order of events as the processing order,nor can they directly take the received minimum timestamp event as the current event to be processed,because it cannot determine whether there are smaller timestamp events still transmitted on the network and not yet received.Therefore,we propose a DIA consistency control method (CCM_SE) based on periodic sampling and event sequence number,which includes two aspects:periodic sampling mechanism and event sequence number mechanism. In order to ensure event total order in CCM_SE,events occurring on different nodes are sorted by timestamps,and the event sequence number mechanism is used to determine whether an event can be submitted for execution to improve the responsiveness of the DIA events. Simulation shows that the CCM_SE has better scalability and response,and can effectively reduce the occurrence of inconsistency in DIA.