设系统中有3种类型的资源(A,B,C)和5个进程P1,、P2、P3、P4、P5,A资源的数量为17,B资源的数量为5,C资源的数量为20。在T0时刻系统状态如下表所示。系统采用银行家算法实现死锁避免策略。
时间: 2024-05-21 16:13:51 浏览: 25
| 进程 | Max需求 | 已分配 | 需求 | 可用 |
| --- | --- | --- | --- | --- |
| P1 | A:7 B:5 C:0 | A:1 B:2 C:0 | A:6 B:3 C:2 | A:9 B:3 C:8 |
| P2 | A:3 B:2 C:2 | A:3 B:0 C:2 | A:0 B:2 C:0 | |
| P3 | A:9 B:0 C:2 | A:2 B:2 C:0 | A:7 B:0 C:2 | |
| P4 | A:2 B:2 C:2 | A:2 B:2 C:1 | A:0 B:0 C:1 | |
| P5 | A:4 B:3 C:3 | A:1 B:0 C:1 | A:3 B:3 C:2 | |
其中,“Max需求”表示进程所需的最大资源数量,“已分配”表示已经分配给进程的资源数量,“需求”表示进程还需要的资源数量,“可用”表示当前系统中可用的资源数量。
根据银行家算法,每个进程需要满足以下条件才能获得资源:
1. 进程已经获得的资源加上需要的资源不能超过最大需求;
2. 进程请求的资源不能超过可用资源数量。
现在假设P1请求A:2、B:1、C:1的资源,请问系统是否会发生死锁?如果不会,系统会如何分配资源?如果会,系统会如何处理?
相关问题
yolov5中的p1 p2 p3 p4 p5
在YOLOv5中,P1、P2、P3、P4和P5是指不同的特征金字塔层。特征金字塔是一种用于检测不同尺度目标的技术,它通过在网络中添加多个分支来处理不同尺度的特征。
具体来说,P1是最底层的特征金字塔层,它通常对应于输入图像的最大尺度。P2、P3、P4和P5则是通过下采样和上采样操作从P1生成的,每个层都对应于不同的尺度。
P1通常用于检测较大的目标,而P2、P3、P4和P5则用于检测较小的目标。这种多尺度的设计可以提高目标检测算法对不同尺度目标的检测能力。
process p1 p2 p3 p4 p5 burst time 10 1 2 1 5 priority 3 1 3 4 2
There are different scheduling algorithms that can be used to schedule these processes based on their burst time and priority. Here are some examples:
1. Priority scheduling: In this algorithm, the processes are scheduled based on their priority. The process with the highest priority gets executed first. If two or more processes have the same priority, then the one with the shortest burst time is executed first. Using this algorithm, the order in which the processes will be executed is:
P2 (burst time: 1, priority: 1)
P5 (burst time: 5, priority: 2)
P1 (burst time: 10, priority: 3)
P3 (burst time: 2, priority: 3)
P4 (burst time: 1, priority: 4)
2. Shortest job first (SJF) scheduling: In this algorithm, the processes are scheduled based on their burst time. The process with the shortest burst time gets executed first. If two or more processes have the same burst time, then the one with the highest priority is executed first. Using this algorithm, the order in which the processes will be executed is:
P2 (burst time: 1, priority: 1)
P4 (burst time: 1, priority: 4)
P3 (burst time: 2, priority: 3)
P5 (burst time: 5, priority: 2)
P1 (burst time: 10, priority: 3)
3. Shortest job first with aging: This is a variation of the SJF algorithm where the priority of a process increases as it waits in the queue. This is done to prevent starvation of processes with high burst time. Using this algorithm, the order in which the processes will be executed is:
P2 (burst time: 1, priority: 1)
P4 (burst time: 1, priority: 2)
P3 (burst time: 2, priority: 4)
P5 (burst time: 5, priority: 5)
P1 (burst time: 10, priority: 6)