进程调度模拟系统(轮转算法、优先级调度算法、最短进程优先算法)c语言
时间: 2023-12-01 19:13:09 浏览: 27
以下是一个简单的进程调度模拟系统,包含轮转算法、优先级调度算法和最短进程优先算法的C语言实现:
```c
#include <stdio.h>
#include <stdlib.h>
#define MAX_PROCESSES 10
typedef struct {
int pid;
int burst_time;
int priority;
int remaining_time;
} Process;
void round_robin(Process processes[], int num_processes, int time_quantum) {
int i, time = 0, completed = 0;
while (completed < num_processes) {
for (i = 0; i < num_processes; i++) {
if (processes[i].remaining_time > 0) {
if (processes[i].remaining_time > time_quantum) {
time += time_quantum;
processes[i].remaining_time -= time_quantum;
} else {
time += processes[i].remaining_time;
processes[i].remaining_time = 0;
printf("Process %d completed at time %d.\n", processes[i].pid, time);
completed++;
}
}
}
}
}
void priority_scheduling(Process processes[], int num_processes) {
int i, j, time = 0, completed = 0;
Process temp;
for (i = 0; i < num_processes; i++) {
for (j = i + 1; j < num_processes; j++) {
if (processes[i].priority > processes[j].priority) {
temp = processes[i];
processes[i] = processes[j];
processes[j] = temp;
}
}
}
while (completed < num_processes) {
for (i = 0; i < num_processes; i++) {
if (processes[i].remaining_time > 0) {
time += processes[i].burst_time;
processes[i].remaining_time = 0;
printf("Process %d completed at time %d.\n", processes[i].pid, time);
completed++;
}
}
}
}
void shortest_job_first(Process processes[], int num_processes) {
int i, j, time = 0, completed = 0;
Process temp;
for (i = 0; i < num_processes; i++) {
for (j = i + 1; j < num_processes; j++) {
if (processes[i].burst_time > processes[j].burst_time) {
temp = processes[i];
processes[i] = processes[j];
processes[j] = temp;
}
}
}
while (completed < num_processes) {
for (i = 0; i < num_processes; i++) {
if (processes[i].remaining_time > 0) {
time += processes[i].burst_time;
processes[i].remaining_time = 0;
printf("Process %d completed at time %d.\n", processes[i].pid, time);
completed++;
}
}
}
}
int main() {
int i, num_processes, time_quantum;
Process processes[MAX_PROCESSES];
printf("Enter the number of processes: ");
scanf("%d", &num_processes);
for (i = 0; i < num_processes; i++) {
printf("Enter the burst time and priority for process %d: ", i + 1);
scanf("%d %d", &processes[i].burst_time, &processes[i].priority);
processes[i].pid = i + 1;
processes[i].remaining_time = processes[i].burst_time;
}
printf("Enter the time quantum for round-robin scheduling: ");
scanf("%d", &time_quantum);
printf("Round-robin scheduling:\n");
round_robin(processes, num_processes, time_quantum);
printf("\nPriority scheduling:\n");
priority_scheduling(processes, num_processes);
printf("\nShortest job first scheduling:\n");
shortest_job_first(processes, num_processes);
return 0;
}
```
在这个例子中,我们定义了一个 `Process` 结构体来表示进程,包含进程ID、CPU占用时间、优先级和剩余时间。我们实现了三种不同的调度算法:
- 轮转算法:使用一个时间片来轮流执行进程,直到所有进程完成。
- 优先级调度算法:按照进程的优先级对进程进行排序,并依次执行所有进程直到完成。
- 最短进程优先算法:按照进程的CPU占用时间对进程进行排序,并依次执行所有进程直到完成。
你可以根据需要修改算法的实现细节,例如添加等待队列、输出更详细的调度信息等等。