操作系统实验2：进程调度策略的模拟实现 1、 设计一个有 N个进程共行的进程调度程序。 2、 每个进程有一个进程控制块PCB来表示，进程控制块的格式为： 进程名 优先数 到达时间 需要运行时间 已占用CPU时间 进程状态 a) 进程优先数、需要运行时间、到达时间可以事先人为地指定，也可以随机产生，注意初始化上述数值时要尽量使进程并发执行，而不是按到达时间顺序调度。 b) 进程的运行时间以时间片为单位进行计算。 c) 进程状态分为就绪、运行、完成三种状态之，分别用W、R、F表示。 3、 进程调度规则如下： a) 就绪进程获得 CPU后都只能运行一个时间片。用已占用CPU时间加1来表示。 b) 如果运行一个时间片后，进程已占用 CPU时间达到所需要运行时间，则进程完成，撤销该进程。 c) 如果运行一个时间片后，进程已占用CPU时间还未达到所需要运行时间，即进程需要继续运行，将它插入就绪队列，队列重新排序，等待CPU。 d) 重复以上过程，直到所要进程都完成为止。 -two experimental operating system : the process of scheduling strategy to achieve a simulation. Design is a process of a total of N the process scheduler. 2, each process is a process control block to PCB said that the process control block format : process a few who arrived at the priority needs time to time running CPU time a state process) process priority number. need to run time, arriving in time prior to artificially designated, can also randomly generated, Initialization attention to the above values are to m

多线程序访问数据库-multi-lane access to the database procedures

进程管理子系统，希望喜欢-process management subsystem, like

a USB drive for safe removal!!

在操作系统存储器的管理方式中若采用一次性将作业全部装入内存的方式-the operating system memory management approaches to the use of one-time operations loaded into memory all the way

线程的同步 　　虽然多线程能给我们带来好处，但是也有不少问题需要解决。例如，对于像磁盘驱动器这样独占性系统资源，由于线程可以执行进程的任何代码段，且线程的运行是由系统调度自动完成的，具有一定的不确定性，因此就有可能出现两个线程同时对磁盘驱动器进行操作，从而出现操作错误；又例如，对于银行系统的计算机来说，可能使用一个线程来更新其用户数据库，而用另外一个线程来读取数据库以响应储户的需要，极有可能读数据库的线程读取的是未完全更新的数据库，因为可能在读的时候只有一部分数据被更新过。-thread synchronization Although multithreading can bring us benefits, but there a lso many problems to be solved. For example, as disk drives such exclusivity system resources and can thread the process of implementation of any code, and the thread running by the scheduling system automatically and to a certain extent the uncertainty, So, then there could be two threads while the disk drives operate, which have operational errors; For example, For the computer banking system, may use a thread to update users of its database, and use another thread to read a database to respond to the needs of depositors, Reading is very likely to read threads database is not fully update the database, Reading may be because the time was only part of the updated dat

可以加载进程，并查看它在内存中程序、连接库及各种数据的地址映象-can loading process, and view it in the memory process, library data and the address mapping

本原代码是基于C语言的原程序。是用 C语言实现的SQL语言-primitive code is based on the C language of the original procedure. C is the language of SQL language

设计一个有 N个进程并发运行的进程调度程序，进程调度算法 ：最高优先数优先的调度算法 。本实验模拟在单处理机环境下处理机的调度，了解处理机调度的过程。-design is a complicated process N-running process scheduler, process scheduling algorithm : the highest priority to a few priority scheduling algorithm. The experimental simulation of the single-processor environment processor scheduling, understanding processor scheduling process.

实现简单的系统进程管理。可察看当前系统中正在运行的进程，进程的基本信息。（如：进程大小、线程ID等)可终止某一进程。-simple realization of a systematic process management. Can see the current system running processes, the process of basic information. (Eg : Process size, thread ID, etc.) may terminate a process.