时间片轮转RR进程调度算法(华侨大学)

《操作系统》实验二内实验报告作者：mo唏【实验题目】：时间片轮转RR进程调度算法【实验目的】通过这次实验，加深对进程概念的理解，进一步掌握进程状态的转变、进程调度的策略及对系统性能的评价方法。

【实验内容】问题描述：设计程序模拟进程的时间片轮转RR调度过程。

假设有n个进程分别在T1, …,T n时刻到达系统，它们需要的服务时间分别为S1, …,S n。

分别利用不同的时间片大小q，采用时间片轮转RR进程调度算法进行调度，计算每个进程的完成时间，周转时间和带权周转时间，并且统计n个进程的平均周转时间和平均带权周转时间。

程序要求如下：1）进程个数n；每个进程的到达时间T1, …,T n和服务时间S1, … ,S n；输入时间片大小q。

2）要求时间片轮转法RR调度进程运行，计算每个进程的周转时间，带权周转时间，并且计算所有进程的平均周转时间，带权平均周转时间；3）输出：要求模拟整个调度过程，输出每个时刻的进程运行状态，如“时刻3：进程B开始运行”等等；4）输出：要求输出计算出来的每个进程的周转时间，带权周转时间，所有进程的平均周转时间，带权平均周转时间。

[ 源程序]程序结构:Process.javapackage com.RoundRobin;/*** 功能：* 定义进程类* method:* 进程按到达时间排序* 进程RR 时间片轮转法* @author Rain**/class Process {private String name; //进程名private int arriveTime; //到达时间private int serviceTime; //服务时间private int finishTime; //完成时间private int roundTime; //周转时间private double weightroundTime; //带权周转时间private double aveweightroundTime; // 平均带权周转时间private double averoundTime; //平均带权周转时间private int temp;private boolean isAction;public Process() {name = "";arriveTime = 0;serviceTime = 0;finishTime = 0;roundTime = 0;weightroundTime = 0;averoundTime = 0;aveweightroundTime = 0;temp = 0;isAction = false;}public void setName(String name) { = name;}public void setArriveTime(int arriveTime) { this.arriveTime = arriveTime;}public void setServiceTime(int serviceTime) { this.serviceTime = serviceTime;this.temp = serviceTime;}public void sort(Process[] a) { //对进程进行排序for (int j = 1; j < a.length; j++) {Process b = a[j];int temp = a[j].arriveTime;int jj = j - 1;while (jj >= 0) {if (temp < a[jj].arriveTime) {a[jj + 1] = a[jj];jj--;} elsebreak;}a[jj + 1] = b;}//for}//sort/**** @param a* @param q* 时间片轮转算法*/public void RR(Process[] a, int q) {Queue aQueue = new Queue();aQueue.enqueue(0);int j;int i = 1;int time = a[0].finishTime;int count = 0;for (int m = 0; m < a.length; m++)count += a[m].serviceTime;int temp = -1;while (!aQueue.isEmpty()) {a[aQueue.front()].temp = a[aQueue.front()].temp - q;if (a[aQueue.front()].temp >= 0) {System.out.print("第"+time);time = q + time;a[aQueue.front()].finishTime = time;System.out.println("到" + a[aQueue.front()].finishTime + "时间刻"+"进程"+ a[aQueue.front()].name+"在运行");}if (a[aQueue.front()].temp < 0) {System.out.print("第"+time);time = a[aQueue.front()].temp + q + time;a[aQueue.front()].finishTime = time;System.out.println("到" + a[aQueue.front()].finishTime + "时间刻" + "进程"+ a[aQueue.front()].name + "在运行");a[aQueue.front()].temp = 0;}for (j = i; j < a.length; j++) {if (a[j].arriveTime <= time) {a[j].isAction = true;aQueue.enqueue(j);i++;}else continue;}if (a[aQueue.front()].temp== 0){a[aQueue.front()].finishTime = time;if(aQueue.isEmpty() != true){aQueue.dequeue();}}else{temp=aQueue.front();aQueue.dequeue();aQueue.enqueue(temp);}}for(int jj=0; jj<a.length; jj++){a[jj].roundTime = a[jj].finishTime - a[jj].arriveTime;a[jj].weightroundTime = (double)a[jj].roundTime / a[jj].serviceTime;a[0].aveweightroundTime += a[jj].weightroundTime;a[0].averoundTime += a[jj].roundTime;}a[0].aveweightroundTime = a[0].aveweightroundTime / a.length;a[0].averoundTime = a[0].averoundTime / a.length;}//RR/*** 打印结果* @param a** */public void print(Process[] a) {System.out.println("进程名" + " " + "到达时间" + " " + "服务时间" + " " + "完成时间"+ " " + "周转时间" + " " + "带权周转时间");//DecimalFormat df = new DecimalFormat("#.00");for (int ii = 0; ii < a.length; ii++) {System.out.println(" " + a[ii].name + " " + a[ii].arriveTime+ " " + a[ii].serviceTime + " "+ a[ii].finishTime + " " + a[ii].roundTime+ " " + Math.floor( a[ii].weightroundTime*100+0.5 )/100 );}System.out.println("RR算法的平均周转时间为：" + Math.floor( a[0].averoundTime*100+0.5 )/100 );System.out.println("RR算法的平均带权周转时间："+ Math.floor( a[0].aveweightroundTime*100 + 0.5 )/100 );}//print}Queue.javapackage com.RoundRobin;import java.util.NoSuchElementException;/*** 自定义队列来存储进程* 通过数组来实现队列**/class Queue {// 字段public static int[] data;// 队列的元素个数protected int size;// 队列头protected int head;// 队列尾public static int tail;// 无参数构造函数public Queue() {final int INITIAL_LENGTH = 100;data = new int[INITIAL_LENGTH];size = 0;head = 0;tail = -1;}// 队列元素个数方法public int size() {return size;}public boolean isEmpty() {return size == 0;}// 得到队列头元素public int front() {if (size == 0)throw new NoSuchElementException();else return data[head];}// 进入队列enqueue()方法public void enqueue(int obj) {// 此时队列已经满if (size == data.length) {int[] oldData = data;data = new int[data.length * 2];if(head == 0)System.arraycopy(oldData, head, data, 0, oldData.length - head);if (head > 0)System.arraycopy(oldData, 0, data, head + 1, tail + 1);head = 0;tail = oldData.length - 1;}tail = (tail + 1) % data.length;size++;data[tail] = obj;}// 队列的元素出队public int dequeue() {if (size == 0)throw new NoSuchElementException();int ele = data[head];// 循环队列//head++;head = (head + 1) % data.length;size--;return ele;}}RR.javapackage com.RoundRobin;import java.io.*;import java.util.Scanner;import com.RoundRobin.Process ;public class RR {/*** @param args*/public static void main(String[] args) {// TODO Auto-generated method stubSystem.out.println("\n--------模拟操作系统进程调度---- 时间片轮转法-----");int i = 0;String[] S1 = new String[20];try {FileReader aFileReader = new FileReader("data.txt");BufferedReader in = new BufferedReader(aFileReader);String s = null;while ((s = in.readLine()) != null) {S1[i] = s;i++;}aFileReader.close();in.close();} catch (IOException ioe) {System.out.println( ioe.getMessage() );}int choice=-1;while( true ){System.out.println(" 1.开始或继续：");System.out.println(" 0.退出。