操作系统先来先服务python精要.docx

操作系统大作业 用python语言编写程序，计算每个进程分别在先来先服务，短进程优先，长进程优先下的平均周转时间，带权周转时间。其中增加了高响应比优先和优先级调度算法。 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30#coding=utf-8 import __main__ import string def fcfs(come_time,run_b_t,run_e_t,run_t,order): #先来先服务 time_temp=come_time[0] for i in range(n): run_b_t[i]=time_temp run_e_t[i]=run_b_t[i]+run_t[i] time_temp=run_e_t[i] n_schedul=i order[n_schedul]=i+1 return come_time,run_b_t,run_e_t,run_t,order def ps(come_time,run_b_t,run_e_t,run_t,order,_prio,run_f): #优先级调度 i=0 max_priority=_prio[i] j=1 while jn and come_time[i]==come_time[j]: if _prio[j]_prio[i]: max_priority=_prio[j] i=j j+=1 #查找第一个被调度的进程 对第???个被调度的进程求相应的参数 n_schedul=i run_b_t[n_schedul]=come_time[n_schedul] run_e_t[n_schedul]=run_b_t[n_schedul]+run_t[n_schedul] run_f[n_schedul]=1 temp_time=run_e_t[n_schedul] order[n_schedul]=1 temp_n=1 while temp_nn: max_priority=0 for j in range(n): if come_time[j]=temp_time and run_f[j] == 0: if _prio[j]max_priority: max_priority=_prio[j] n_schedul=j #查找下一个被调度的进程 #对找到的下一个被调度的进程求相应的参数 run_b_t[n_schedul]=temp_time run_e_t[n_schedul]=run_b_t[n_schedul]+run_t[n_schedul] run_f[n_schedul]=1 temp_time=run_e_t[n_schedul] temp_n+=1 order[n_schedul]=temp_n def sjf(come_time,run_b_t,run_e_t,run_t,order,_prio,run_f): #短作业优先 i=0 run_time=run_t[i] j=1 while jn and come_time[i]==come_time[j]: if run_t[j]run_t[i]: run_time=run_t[j] i=j j+=1 #查找第一个被调度的进程 #对第一个被调度的进程求相应的参数 n_schedul=i run_b_t[n_schedul]=come_time[n_schedul] run_e_t[n_schedul]=run_b_t[n_schedul]+run_t[n_schedul]