处理机调度操作系统试验报告

1、精品资料学年第 学期操作系统课程学 专 班 姓 学实验报告级：名：号：任课教师：实验题目处理机调度实验地点实验目的1. 通过编写程序实现进程或作业先来先服务、高优先权、按时间片轮转调度算 法，进一步掌握进程调度的概念和算法，加深对处理机分配的理解。2. 了解Linux中进程(线程)的调度机制。3. 学习使用Linux中进程(线程)调度算法，掌握相应的与调度有关的函数。实 验 内 容1、程序说明：(1) 先来先服务算法：如果早就绪的进程排在就绪队列的前面，迟就绪的进程排在就绪队列的后面，那么先来先服务(FCFS first comefirst service )总是把当前处于就 绪队列之首的那个

2、进程调度到运行状态。(2) 轮转法就是按一疋时间片(记为q)轮番运行各个进程。如果q是一个疋值，则轮转 法是一种对各进程机会均等的调度方法。(3) 优先级调度的基本思想是，把当前处于就绪队列中优先级最高的进程投入运行，而 不管各进程的下一个CPL周期的长短和其他因素。2、具体步骤：(1) 分析问题，提出解决问题的算法(2) 编制程序(3) 程序调试(4) 记录实验结果，以及思考是否能够改善算法(1)编辑程序jcdd.c，编译并执行。#i nclude #i nclude #defi ne P_NUM 5#defi ne P_TIME 50enum stateready,execute,bloc

3、k,fin ish;struct pcbbchar n ame4;in t priority; /数越大优先级越咼int cputime; /已占用CPU勺时间int needtime; /执行时间int count;enum state process;struct pcbb *n ext;typedef struct pcbb pcb;void display me nu ()printf(CHOOSE THE ALGORITHM);prin tf(1 PRIORITY n);prin tf(2 ROUNDROBINn ”);prin tf(3 EXIT n);pcb* get_proce

4、ss()pcb *q;pcb *p; II头指针pcb *t; II尾指针int i = 0;prin tf(i nput n ame and time n);while (i n ame);scan f(%d, &q- needtime);q-cputime = 0;q-priority = P_TIME - q-n eedtime;q-process = ready;q- next = NULL;if(i=0)p = q; t = q;elset_n ext = q;t = q;i+;return p;void free_process(pcb *p)pcb *q;while(p!= NU

5、LL)q = p;p = p_n ext;free(q);void display(pcb *p)printf(n ame cputime n eedtimeprioritystate n);while(p)prin tf(%s,p-n ame);printf();prin tf(%d,p-cputime);printf(”)；prin tf(%d,p- needtime); printf();prin tf(%d,p-priority);printf();switch(p-process)case ready:pri ntf(readyn );break;case execute:pri n

6、tf(executen); break;case block:pri ntf(block n); break; case fini sh:pri ntf(fi nishn); break;p = p_n ext;int process_fi ni sh(pcb *q)int b1 = 1;while(b1 &q)b1 = b1&q- needtime=O;q = q_n ext;return b1;void cpuexe(pcb *q)pcb *t = q;int tp = 0;while(q) /让t指向优先级最高的进程if (q-process!=fi ni sh) q-process =

7、 ready; if(q-n eedtime=0) q-process = fini sh;if(tppriorit y&q-process!=fi ni sh)tp = q-priority;t = q;q = q_n ext;if(t- needtime!=0)t-priority -=3; /每执行一次优先级降低二个单位t-n eedtime -;t-process = execute; t-cputime+;void priority_cal()pcb *p;p = get_process();int cpu = 0;while(!process_fi ni sh(p) /就绪队列中还

8、有进程cpu+;prin tf(cputime:%dn,cpu);cpuexe(p); /选择优先级取咼的进程执行一个时间单位display(p); /每调度一次就显示次sleep(2); free_process(p); /释放所有进程prin tf(All processes have fini shedn);pcb *get_process_r oun d()pcb *q;pcb *p; II头指针pcb *t; II尾指针int i = 0;prin tf(i nput n ame and timen);while (in ame); scan f(%d, &q- needtime);

9、q-cputime = 0; q-co unt = 0;q-process = ready;q- next = NULL; if(i=0)p = q; t = q; else t_n ext = q; t = q;i+;return p;void cpu_r oun d(pcb *q)if(q-n eedtime=1) q-cputime+;elseq-cputime +=2;q-n eedtime -=2;if(q-n eedtimen eedtime = 0;q-co un t+;q-process = execute;pcb *get_ next(pcb *k,pcb *head)pcb

10、 *t;t = k;dot =t- n ext;while ( t & t-process = fini sh);if(t = NULL)t = head;/k是刚刚被执行的节点，如果t-next=k,所明就绪队列除了 k和t以外都已结束，按照时间 片轮转算法，该t执行while(t- n ext!=k & t-process = fin ish)t = t-n ext;return t;void set_state(pcb *p)while(p)if(p-n eedtime = 0) p-process = fini sh;if(p-process = execute) p-process

11、= ready;p = p_n ext; void display_r oun d(pcb *p)printf(n ame cputime n eedtimecountstaten);while(p)prin tf(%s,p-n ame);printf();prin tf(%d,p-cputime);printf();prin tf(%d,p- needtime);printf();prin tf(%d,p-cou nt);printf();switch(p-process)case ready:pri ntf(readyn );break;case execute:pri ntf(execu

12、ten); break;case block:pri ntf(block n); break;case fini sh:pri ntf(fi nishn); break;p = p_n ext;void roun d_cal()pcb *p;pcb *r;p = get_process_r oun d();int cpu = 0;r=p;while(!process_fi ni sh(p) /就绪队列中还有进程if(r-n eedtime=1)cpu+=1;elsecpu+=2; /时间片长度是2cpu_r oun d(r);r = get_ next(r,p); /获得下一个需要执行的进程p

13、rin tf(cputime:%dn,cpu);display_rou nd(p); /每调度一次就显示次set_state(p);sleep(2); free_process(p); /释放所有进程mai n()display_me nu();int k;sca nf(%d,&k);switch(k)case 1:priority_cal();break;case 2:r oun d_cal();break;case 3: break;default:pri ntf(YOU HAVE NOT CHOOSE ANY ALGORITHM!”)； (2)编辑程序先来先服务调度算法fcfs.c,编译

14、并执行。#i nclude #i nclude int SUM=0,K=0;typedef struct linkint time;int averageTime;int priority;struct link *n ext;li nkno de;linknode *creat()int n,m;linknode *head,*r,*s;head=r=(li nknode *)malloc(sizeof(li nkno de);printf(输入各进程的处理时间和优先级并以两个0为结束标志:n);while(sca nf(%d %d,&n,&m)&n&m)s=(l inknode *)mal

15、loc(sizeof(li nkno de);K+;s-time=n;s_priority=m;s-averageTime=0;r-n ext=s;r=s;r-n ext=NULL;retur n head;linknode *seekAverageTime(li nknode *head)int sum=0;linknode *p;p=head-n ext;while(p)sum=sum+p-time;p-averageTime=sum;p=p-n ext;SUM+=sum;void prin t(l inknode *head)linknode *p;p=head-n ext;prin t

16、f(各进程处理时间为：);while(p)prin tf(%-4d,p-averageTime); p=p-n ext;prin tf(n);mai n()linknode *head;head=creat();seekAverageTime(head);prin t(head);printf(”平均处理时间为：%dn,(SUM/K);(1)优先级调度unspgunsp-virtual-machinej-s gee jcdd.c -o jedd un5paun5p-virtualmachine；S CHOOSE THE ALGORITHM:1 PRIORITY2 ROUNDflOBIN3 EX

17、IT1input name and1221,/jcddtime1234cputime:1 namecputime1GQeeneedtime622priority4648484947state executeready ready reddy ready|cputime:2namecputimeneedtimeprioritystate61e46finish1G248ready2G2斗8ready31e46execute4e347ready_L Jr.l!：3namecputimeneedtimeprioritystate01646finish11145xecut电26248ready31046

18、finish40347readyIcputtne:4namecputimeneedtimeprioritystate01e46iinish11145ready21145execute31e46finish4e347readylcputime!5namecputimeneedtimeprioritystate1046finish11斗5ready21145ready31e46finish412斗4execute1 cputime；enamecputimeneedtimeprioritystatee1046finish12042execute21145ready31Q46finish4124斗re

19、ady1 cputime:?namecputimeneedtimeprioritystate61$4&finish12042finish22Mexecute31046finish41244ready|cputime:8namecputimeneedtimeprioritystateG1646finish12&42finish22642finish31046finish斗21executecputime:9namecputimeneedtimeprioritystate0146finish12百42finish22642finish31046finish43038executeAllproces

20、ses have finishedunsp(aunsp-virtual-machine ：-$(2)时间片轮转调度unsp(aunsp-virtual-macnine:-s ,/jcdd CHOOSE THE ALGORITHM:1 PRIORITY2 ROUNDROBIN3 EXIT2input name and time6 11 22 23 14 3cputime:1namecputimeneedtimecountstatee161execute1Q2Qready2G2Qready3e10ready4Q3flreddycputime：3 name 0cpu tinif12eQi6necdtimeG62count1state finish execute ready ready readykputime： 5name6234cputime:6 name612b匚putime12200needtime6e01