任务1：进程调度

1 设计目的

（1）要求学生设计并实现模拟进程调度的算法：时间片轮转及先来先服务。

（2）理解进程控制块的结构。

（3）理解进程运行的并发性。

（4）掌握进程调度算法。

2 设计要求

在多道程序运行环境下，进程数目一般多于处理机数目，使得进程要通过竞争来使用处理机。这就要求系统能按某种算法，动态地把处理机分配给就绪队列中的一个进程，使之运行，分配处理机的任务是由进程调度程序完成的。一个进程被创建后，系统为了便于对进程进行管理，将系统中的所有进程按其状态，将其组织成不同的进程队列。于是系统中有运行进程队列、就绪队列和各种事件的进程等待队列。进程调度的功能就是从就绪队列中挑选一个进程到处理机上运行。进程调度的算法有多种，常用的有优先级调度算法、先来先服务算法、时间片轮转算法。

-Task 1: Process scheduling

1 designed

(1) requires students to design and implement simulation process scheduling algorithms: time slice rotation, and a first-come, first served.

(2) understand the process control block structure.

(3) understand the process to run concurrency.

(4) to master the process of scheduling algorithm.

2 design

Run in a multi-channel environment, the number of processors than the number of processes generally, makes the process to be used by competitive processors. This requires the system by an algorithm can be dynamically assigned to the processor ready queue of a process to make it run, assign processor scheduler task is accomplished by the process. A process is created, the system in order to facilitate the management of the process, the system according to the state of all processes will be organized into different processes its queue. So the system has run the process queue, ready queue and wait queue process events. Process scheduling funct