describe the life circle of process and why each process must have one PCB.

 

Create a new process, if admitted, it will enter the ready state. When scheduler dispatch , the process will start running, the instruction will be executed, if there are other processes running, the process will become waiting or ready state, if it is running Interrupt, the process will return to the ready state, when the process runs successfully, the process will exit and terminated.

 

The PCB records all the information required by the operating system to describe the current state of the process and control the running of the process. In a word, the OS controls and manages the concurrent execution process according to the PCB.