计算机操作系统实验报告.doc

操作系统课程设计报告学 院 计算机 专 业 计算机科学与技术 班 级 2011级1班 题 目 实现处理机调度模块功能 学 号 姓 名 指导教师 丁国芳 一、 采用具有二级调度的调度队列模型。其中作业调度采用先来先服务策略，进程调度采用时间片轮转调度算法。二、利用银行家算法避免死锁。三、课程设计要求：1. 系统总共运行100个作业。为每个进入后备队列的作业创建一个JCB，内容包括：作业标识、预计运行时间、资源需求等。其中预计运行时间和资源需求随机生成（120个时间片，A资源0-5，B资源0-3，C资源0-4）。2. 系统开始从后备队列中调入10个作业进入系统。以后每完成一个作业就从后备队列中调入一个，直到所有作业完成。3. 系统为每个作业创建一个进程，按JCB分配系统资源。共有3类系统资源，其中A类资源50个，B类资源30个，C类资源40个）。4. 进程在运行过程中（即每个时间片内），可能会申请新的资源（申请的各类资源个数均不超过2）。用银行家算法控制资源的分配，避免死锁。注意，每个进程申请各类资源的数目不能超过系统资源总数的二分之一。5. 创建三个阻塞队列A、B、C，分别记录因资源请求而阻塞的进程。6. 可视化编程，形象地展现进程运行的状态。四、代码实现：using System;using System.Collections.Generic;using System.Text;using System.Windows.Forms;namespace process_scheduling public partial class Form1 : Form StringBuilder sb = new StringBuilder(); static int timeflat = 0; static int, max = new int100, 3; static int, allocation = new int100, 3; static int, need = new int100, 3; public struct JCB public int flag; public String name;/作业名 public int servertime;/服务时间 public int arrivetime;/到达时间 public int remaintime;/剩余服务时间 public int f;/阻塞时获得资源变成就绪状态标志 ; Queue pqueue = new Queue();/后备队列 Queue rqueue = new Queue();/就绪队列 Queue blockA = new Queue();/阻塞A队列 Queue blockB = new Queue();/阻塞B队列 Queue blockC = new Queue();/阻塞C队列 int resource = new int3 50, 30, 40 ;/分别是资源A ,B,C 和它们的数量 static JCB job = new JCB100; public Form1() InitializeComponent(); private void Form1_Load(object sender, EventArgs e) sb.Append(); Random rd = new Random(); for (int i = 0; i 0) timeflat = Convert.ToInt32(tb_timeflat.Text); else if (tb_timeflat.Text.Length = 0) sb.Append(请输入时间片!); sb.Append(Environment.NewLine); tb_content.Text = sb.ToString(); if (timeflat 20) sb.Append(时间片大小不合法!); sb.Append(Environment.NewLine); tb_content.Text = sb.ToString(); else run(); public void run() int count = 0; for (int i = 0; i count) if (blockA.Count = 0 & blockB.Count = 0 & blockC.Count = 0) sb.Append(count.ToString(); sb.Append( 处理机处理空转 ); sb.Append(Environment.NewLine); count+; else wakeup(); else JCB pro1 = new JCB(); pro1 = rqueue.Dequeue(); if (allocationpro1.flag, 0 = maxpro1.flag, 0) if (allocationpro1.flag, 1 = maxpro1.flag, 1) if (allocationpro1.flag, 2 = maxpro1.flag, 2) if (pro1.remaintime = timeflat&pro1 .servertime =timeflat ) pro1.remaintime -= timeflat; sb.Append(时间: 作业名: 服务总时间: 剩余服务时间 状态 ); sb.Append(Environment.NewLine); sb.Append(count); sb.Append(-); sb.Append(count +timeflat) ); sb.Append( ); sb.Append(pro1 .name ); sb.Append( ); sb.Append(pro1 .servertime ); sb.Append( ); sb.Append(pro1 .remaintime ); if(pro1 .remaintime=0) sb.Append( 进程结束 ); else sb.Append( 运行中 ); sb.Append(Environment .NewLine ); count += timeflat;/当前时间加上时间片 if (pro1.remaintime != 0) addprocess(ref count ,9);/加回之前确保在这之前的进程加入到就绪队列里,9确保能有位置加入 rqueue.Enqueue(pro1);/加回就绪队列 showqueue(rqueue ); else sb.Append(时间: 作业名: 服务总时间: 剩余服务时间 状态 ); sb.Append(Environment.NewLine); sb.Append(count); sb.Append(-); sb.Append(count + pro1.remaintime ); sb.Append( ); sb.Append(); sb.Append( ); sb.Append(pro1.servertime); sb.Append( ); sb.Append(0 进程结束 ); sb.Append(Environment.NewLine); count += pro1 .remaintime ;/当前时间加上时间片 pro1.remaintime = 0;/服务时间 /进程结束查看阻塞队列 if (pro1.remaintime = 0) relaxresource(pro1); wakeup(); else sb.Append(pro1 .name ); sb.Append(阻塞 ); sb.Append(Environment.NewLine); blockC.Enqueue(pro1); else sb.Append(); sb.Append(阻塞 ); sb.Append(Environment.NewLine); blockB.Enqueue(pro1); else sb.Append(); sb.Append(阻塞 ); sb.Append(Environment.NewLine); blockA.Enqueue(pro1); tb_content.Text = sb.ToString(); /银行家算法 private int allocationarithmetic(int i, int requestA, int requestB, int requestC) int rtn = 1; /资源A if (requestA = resource0 & requestA 0) resource0 -= requestA;/减去相应资源 needi, 0 -= requestA;/减去相应需求资源数 allocationi, 0 += requestA;/增加相应资源数 else rtn = -1; /资源B if (requestB = resource1 & requestB 0) resource1 -= requestB;/减去相应资源 needi, 1 -= requestB;/减去相应需求资源数 allocationi, 1 += requestB;/增加相应资源数 else rtn = -1; /资源C if (requestC = resource2 & requestC 0) resource2 -= requestC;/减去相应资源 needi, 2 -= requestC;/减去相应需求资源数 allocationi, 2 += requestC;/增加相应资源数 else rtn = -1; if (rtn != -1) / Console.WriteLine(进程请求量出现错误,请核实后在运行程序!); /else rtn = safearithmetic(); if (rtn = 0)/此分配方案导致系统不安全 if (requestA 0) resource0 += requestA;/加上相应资源 needi, 0 += requestA;/加上相应需求资源数 allocationi, 0 -= requestA;/减去相应资源数 if (requestB 0) resource1 += requestB;/加上相应资源 needi, 1 += requestB;/加上相应需求资源数 allocationi, 1 -= requestB;/减去相应资源数 if (requestC 0) resource2 += requestC;/加上相应资源 needi, 2 += requestC;/加上相应需求资源数 allocationi, 2 -= requestC;/减去相应资源数 return rtn; /安全算法 private int safearithmetic() int finish = new int10;/完成工作量 int work = new int3;/现有资源记录量 int, record = new int10, 3;/记录就绪队列中每个进程的需求量 int, allocate = new int10, 3;/记录就绪队列中每个进程已分配的资源量 int i = 0; work0 = resource0; work1 = resource1; work2 = resource2; foreach (JCB item in rqueue) recordi, 0 = needitem.flag, 0;/进程对资源A的需求量 recordi, 1 = needitem.flag, 1; recordi, 2 = needitem.flag, 2; allocatei, 0 = allocationitem.flag, 0; allocatei, 1 = allocationitem.flag, 1; allocatei, 2 = allocationitem.flag, 2; i+; i = 0; while (i 10) if (recordi, 0 = work0 & recordi, 1 = work1 & recordi, 2 = work2 & finishi = 0) work0 += allocationi, 0; work1 += allocationi, 1; work2 += allocationi, 2; finishi = 1; i = 0; else i+; int flg = 1; for (i = 0; i 0) jp1 = blockA.Peek(); if (needjp1.flag, 0 0) jp1 = blockB.Peek(); if (needjp1.flag, 1 = 2)/请求资源 request(ref jp1, 0, needjp1.flag, 1, 0); else request(ref jp1, 0, 2, 0); if (jp1.f = 1 & jp1.flag 0) jp1 = blockC.Peek(); if (needjp1.flag, 2 = 2)/请求资源 request(ref jp1, 0, 0, needjp1.flag, 2); else request(ref jp1, 0, 0, 2); if (jp1.f = 1 & jp1.flag jp.flag) jp = blockC.Peek(); bl = 2; if (bl != -1) switch (bl) case 0: jp = blockA.Dequeue(); break; case 1: jp = blockB.Dequeue(); break; case 2: jp = blockC.Dequeue(); break; rqueue.Enqueue(jp);/将已获资源的进程加回到就绪队列中 sb.Append(); sb.Append(进入就绪队列 ); sb.Append(Environment.NewLine); showqueue(rqueue ); private void relaxresource(JCB jcb1) resource0 += allocationjcb1.flag, 0; resource1 += allocationjcb1.flag, 1; resource2 += allocationjcb1.flag, 2; private void addprocess(ref int count,int sum) JCB jb = new JCB(); if (pqueue.Count != 0) jb = pqueue.Peek(); else jb.arrivetime = int.MaxValue; while (jb.arrivetime = count & rqueue.Count 0) pro = pqueue.Dequeue(); /分配资源 if (resource0 - maxpro.flag, 0 = 0) needpro.flag, 0 = 0; allocationpro.flag, 0 = maxpro.flag, 0; resource0 -= maxpro.flag, 0; else allocationpro.flag, 0 = resource0; needpro.flag, 0 = maxpro.flag, 0 - allocationpro.flag, 0; resource0 = 0; if (resource1 - maxpro.flag, 1 = 0) needpro.flag, 1 = 0; allocationpro.flag, 1 = maxpro.flag, 1; resource1 -= maxpro.flag, 1; else allocationpro.flag, 1 = resource1; needpro.flag, 1 = maxpro.flag, 1 - allocationpro.flag, 1; resource1 = 0; if (resource2 - maxpro.flag, 2 = 0) needpro.flag, 2 = 0; allocationpro.flag, 2 = maxpro.flag, 2; resource2 -= maxpro.flag, 2; else allocationpro.flag, 2 = resource2; needpro.flag, 2 = maxpro.flag, 2 - allocationpro.flag, 2; resource2 = 0; rqueue.Enqueue(pro); tb_content.Text = tb_content.Text + .ToString() + 进入系统+Environment .NewLine ; if (pqueue.Count != 0) jb = pqueue.Peek(); /显示当前就绪队列中所有进程信息 private void showqueue(Queue q) sb.Append(当前就绪队列中所有进程信息); sb.Append(Environment .NewLin