Operating System (iii) -- processor management

Operating System (iii) -- processor management

Operating System (iii) -- processor management

Processor management:It can be seen from the meaning of the surface layer that it is processing. They want to process events in their lives. Location

Processor management is used to allocate and schedule processors!

　 　

I. Multi-Channel Programming

Parallel execution of programs: <喎?http: www.bkjia.com kf ware vc " target="_blank" class="keylink"> Signature + signature/bSu7z + signature/J0tSx37D + u6jJ + qGisd/PtL3FoaKx37 + signature/2 zazR + signature/Signature + 1/Signature + signature + o7o8YnI + Signature + CjKhorbUw7/Su7XAzOLAtMu1o6y007 + alias/ycTcsci1pbbA1rTQ0MqxvOSzpKGjPGJyPgo8YnI + Signature =" http://www.2cto.com/uploadfile/Collfiles/20150428/201504281013126.png "Alt =" \ ">

Ii. Process

Program: A set of commands with independent functions. (The execution of the program must depend on the entity, which is a dataset)

-- This is a static state.

Process: An execution of a program on a dataset-a dynamic one.

　Function:
1. improve resource utilization
2. Describe the execution of the program correctly and call the Compilation Program. Translate the source program into the target program.


Process attributes:
1,Dynamic: A process is a dynamic event and a program is static.
2,Asynchronization: Concurrent processes can not be synchronized.
3,Concurrency: Multiple processes can be performed simultaneously.
4. It can contain the same program: in multiple processes, the same process may be executed.


Status: Three




Process Control Block(PCB, Process Control Block) blocks and records the execution status of each Process.
Flag Information: process name
Description information; Process status, waiting reason, process program
Field Information: The same register content, control register content, program status word register content
Management information: Process Priority, queue pointer

Note: Each process is created with a process control block to identify the beginning of process life.

Primitive: An uninterrupted process is called a primitive.
(1)Control primitive Processes: Create a primitive: a workspace or a process control block
(2)Undo: After a process is completed, the workspace and process block of the process are withdrawn.
(3)Blocking: Change process state to wait state
(4)Wake up: The process is in the ready state.


Note:: The first pointer of the queue points to the first process control block of the queue, and the last pointer value is 0.




Departure:A process exits from the queue.

Join: A process is queued into a worthy queue.