高层体系结构中时间管理算法研究及改进

摘要

不恰当的最大安全推进时间(GALT)计算方法会影响系统整体运行,严重情况下可能导致系统死锁,使整个系统仿真无法向前推进.为此,分析经典时间推进Frederick算法中可能出现死锁的情况,给出死锁出现的原因,并对死锁产生的原因进行论证,在此基础上,设计一种基于该算法的改进无死锁时间管理GALT计算算法.分析结果表明,改进算法可以有效解决GALT计算产生的死锁问题.%An inappropriate Greatest Available Logical Time(GALT) algorithm may affect system's whole function and cause deadlock in extreme condition. The deadlock is harmful which prevents system advancing forward. This paper researches deadlock within calculating GLAT, explains reasons of deadlock and proves the reason. It introduces one non-deadlock time management GALT computation algorithm based on Frederick algorithm. In test section, it proves the time advance algorithm's undoubtedly correctness of non-deadlock.