编写一个进程调度程序,实现基于优先权的进程调度算法,要求:输入n个进程的信息:ID,进程名,优先级以及运行时间(以分钟计)。假设进程每等待1分钟,优先权提高1级。输出每经过1分钟间隔各个进程的运行状况。最后统计系统整体的平均周转时间,平均等待时间,平均响应时间。
时间: 2023-06-16 12:08:07 浏览: 245
以下是一个基于优先权的进程调度程序的代码示例:
```python
class Process:
def __init__(self, pid, name, priority, burst_time):
self.pid = pid
self.name = name
self.priority = priority
self.burst_time = burst_time
self.wait_time = 0
self.response_time = 0
self.turnaround_time = 0
def __repr__(self):
return f"Process(pid={self.pid}, name='{self.name}', priority={self.priority}, burst_time={self.burst_time})"
def run_scheduler(processes):
time_quantum = 1
total_burst_time = sum(process.burst_time for process in processes)
current_time = 0
finished_processes = []
while current_time < total_burst_time:
runnable_processes = [process for process in processes if process.burst_time > 0]
highest_priority = max(process.priority for process in runnable_processes)
highest_priority_processes = [process for process in runnable_processes if process.priority == highest_priority]
executing_process = min(highest_priority_processes, key=lambda process: process.burst_time)
executing_process.burst_time -= time_quantum
executing_process.priority += 1
for process in runnable_processes:
if process != executing_process:
process.wait_time += time_quantum
process.priority -= 1
if executing_process.burst_time <= 0:
executing_process.turnaround_time = current_time + time_quantum
executing_process.response_time = executing_process.turnaround_time - executing_process.burst_time
finished_processes.append(executing_process)
current_time += time_quantum
avg_turnaround_time = sum(process.turnaround_time for process in finished_processes) / len(finished_processes)
avg_wait_time = sum(process.wait_time for process in finished_processes) / len(finished_processes)
avg_response_time = sum(process.response_time for process in finished_processes) / len(finished_processes)
print("进程\t运行时间\t等待时间\t响应时间\t周转时间")
for process in finished_processes:
print(f"{process.name}\t{process.burst_time}\t{process.wait_time}\t{process.response_time}\t{process.turnaround_time}")
print(f"平均周转时间: {avg_turnaround_time}")
print(f"平均等待时间: {avg_wait_time}")
print(f"平均响应时间: {avg_response_time}")
if __name__ == '__main__':
processes = [
Process(1, "P1", 3, 10),
Process(2, "P2", 1, 5),
Process(3, "P3", 4, 8),
Process(4, "P4", 2, 7),
]
run_scheduler(processes)
```
在这个例子中,我们首先定义了一个 Process 类,用于存储每个进程的信息。然后,我们实现了一个 run_scheduler 函数,用于实现基于优先权的进程调度算法。
在调度算法中,我们首先计算出当前可运行的进程,并找到其中优先级最高的进程。然后,我们将该进程运行一段时间(这里设定为 1 分钟),并且将其优先级加 1。同时,我们将其他可运行进程的优先级减 1,以模拟等待时间的影响。
如果运行的进程在当前时间段内完成了所有工作,我们将其从可运行进程列表中移除,并记录其周转时间、等待时间和响应时间。最后,我们计算出所有进程的平均周转时间、平均等待时间和平均响应时间,并输出结果。
在上面的例子中,我们假设有 4 个进程,分别为 P1、P2、P3 和 P4。它们的优先级分别为 3、1、4 和 2,运行时间分别为 10、5、8 和 7 分钟。我们可以看到,程序会输出每个进程的运行状况,以及整体的平均周转时间、平均等待时间和平均响应时间。
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