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由于在单道批处理系统中,作业一投入运行,它就占有计算机的一切资源直到作业完成为止,因此调度作业时不必考虑它所需要的资源是否得到满足,它所占用的CPU时限等因素。 每个作业由一个作业控制块JCB表示,JCB包括如下信息:作业名、提交时刻、所需运行时间、所需资源、作业状态、链指针等。 在程序开始时对用户提交的作业按作业调度算法排列,用链表形式存储,这里分别采用先来先服务、短作业、响应比高者优先调度算法对作业进行调度。这里为了操作者的方便,每个作业无论所需运行时间多少,都是每敲一次键盘就执行完一个作业。每个作业完成后打印作业的开始运行时刻,完成时刻,周转时间和带权周转时间,一组作业完成后打印这组作业的平均周转时间,带权周转时间。所以要在运行时对运行时间进行记录,这里设置几个全局变量:T时间量; ttime总周转时间; trtime总的带权周转时间。-Road due to the single-batch system, and put into operation an operation, it has all the resources of the computer until the operation is completed, the dispatch operation when it"s not necessary to consider whether the resources needed to be met, it occupied by the CPU time and other factors. Each operation by operating a control block JCB, JCB include the following information : operations, and submitted moment, the run time, the resources required, operational state, chain pointer. At the beginning of the procedure to users of operations by scheduling algorithm with using forms Chain store, were used here fir