分布式实时系统的集中式相对时钟同步方法  

Centralized relative-clock synchronization for distributed real-time systems

作　　者：谭朋柳[1] 金海[1] 张明虎[1] 

机构地区：[1]华中科技大学计算机科学与技术学院,湖北武汉430074

出　　处：《华中科技大学学报（自然科学版）》2007年第2期16-18,共3页Journal of Huazhong University of Science and Technology(Natural Science Edition)

基　　金：国家自然科学基金资助项目(60273076)

摘　　要：提出了集中式相对时钟同步方法,采用客户机/服务器模式,使用服务器的CPU时钟作为整个系统的全局时钟,时钟服务器周期性地轮换向各客户机发送时钟同步请求,克服了以往同步算法由于网络竞争引起附加延迟而造成的不精确的缺点,同时可以获得比物理时钟更高精度的时钟同步.测试结果表明:时钟同步进程周期在10 s以内时,同步后客户机的时间与服务器同步源的时间的偏离值一般在±5μs以内.集中式相对时钟同步方法具有精度高、安全可靠、成本低三大优点.The centralized relative-clock synchronization method adopts the client/server mode and uses the server＇s CPU-clock as the global reference clock. The time server sends a request for clock synchronization to every client （one per period） periodically. This method overcomes the inaccuracy of the existing clock synchronization methods because of the additional latency caused by the network competition, and can get higher accuracy than the physical clock synchronization method. The experimental results showed that if the synchronization period was less than or equal to 10 s the time deviation between client and server was less than or equal to ±5μs. The centralized relative-clock synchro- nization method has three main advantages： high accuracy, security and reliability, and low cost.

关 键 词：分布式实时系统 相对时钟同步 背离值 

分 类 号：TP311[自动化与计算机技术—计算机软件与理论]