Description of the operating system process and what the operating system does in process management

Specifically, rtlinux? Real-time operating system.

The landlord is so precious that the word is like gold, and it is really difficult to do it

The operating system does the following aspects of process management: process control, process synchronization, process communication, and process scheduling.

1. Process control: Process control is the source code VB that controls the process, and controls the block by manipulating the process. It is a process that makes a program (including data) that cannot run independently in a multi-channel program environment become a basic unit that can run independently or execute concurrently with other processes.

2. Process synchronization: In a multi-channel program environment, the process is executed concurrently. A set of concurrent processes with a synchronization relationship is called a cooperative process, and the signals that cooperative processes send to each other are called messages or events.

3. Process communication: two parallel processes can cooperate by sending messages to each other, and messages are passed between processes through message buffering. A multi-process environment may require processes to cooperate to accomplish a task, and these processes need to coordinate their progress by exchanging information with each other.

Therefore, the system must have the ability to communicate (exchange information) between processes.

4. Process scheduling: The system process also needs to use a processor. This requires the process scheduler to dynamically assign the processor to a process in the ready queue for execution according to a certain policy.

The answer to the question of how the operating system manages processes is as follows.

Process Control Block (PCB) (a special data structure set up by the system to manage the process, which is used to record the external characteristics of the process and describe the movement change process of the process. The system uses the PCB to control and manage the process, so the PCB is the only sign that the system is aware of the existence of the process. The process is one-to-one corresponding to the PCB).

In different operating systems, the control and management mechanism of the process is different, and the information in the PCB is not the same, usually the PCB should contain some of the following information.

1. Process identifier name:

Each process must have a unique identifier, which can be a string or a number.

2. The current status of the process is status:

Describes the current state of the process. For the convenience of management, the system is designed to form a queue of processes in the same state, such as the ready process queue, and the waiting process should form multiple waiting queues according to the waiting events, such as waiting for the printer queue, waiting for the disk IO completion queue, etc.

3. The corresponding program and data address of the process, so as to link the PCB with its program and data.

4. List of process resources. Lists the records of owned resources other than CPUs, such as owned IO devices.

A list of open files, etc.

5. Process priority priority:

The priority of a process reflects the urgency of the process and is usually specified by the user and set by the system.

6. CPU on-site protection zone cpustatus:

When the process can no longer occupy the CPU for some reason (such as waiting for the printer), release the CPU, and then protect the various state information of the CPU so that it can be recovered by the processor again in the future.

The various states of the CPU continue to run.

7. Process synchronization and communication mechanism is used to realize the signals required for mutual exclusion, synchronization and communication between processes.

amount, etc. 8. The link word of the queue PCB where the process is located According to the current state of the process, the process is corresponding.

The first address of the PCB.

9. Other information related to the process. For example, process accounting information, process time occupied by the CPU, etc.

1. Process control: The system must set up a set of control mechanisms to realize the process creation, process undo and the state transformation of the process in the process of operation.

2. Process synchronization: The system must set up a synchronization mechanism to coordinate the operation of all processes, including the mutual exclusion of the process and the synchronization of the process.

3. Process communication: In a multi-process environment, processes may need to cooperate to complete a task, and these processes need to coordinate the progress of their work by exchanging information with each other. Therefore, the system must have the ability to communicate (exchange information) between processes.

4. Process scheduling: The system must be able to select a ready process from the ready process queue according to a certain algorithm when the processor is idle, assign the processor to it, and set the running site for it to put into operation.

Your Q&A is unclear. If you say that you can maintain and optimize the PC yourself, you can use external software, such as optimization master, 360, Swiss Army knife, etc., if you learn the work that can be done by operating system process management, this depends on the situation. It can be a refresher in some aspects of network management, which can be used for general system network maintenance work, or network management.

Hope it helps

The main resource allocation is reflected in the process scheduling, interrupting the request, which will allow the process to perform the task according to the assigned priority or the priority of the process that the request is processed by...

In UNIX systems, processes are tagged using a data structure, the Process Control Block (PCB), which is the only sign of a process's existence.

The process control block stores the process state, the nature of the process (such as priority), the control information related to the process (such as parameters, semaphores, messages, etc.), the corresponding queue, and the field protection area. The process control block is generated with the establishment of the process and undone with the completion of the process, it is one of the most important data structures in the core of the operating system, it is not only the symbol of the existence of the process and the basis of scheduling, but also the basis for the process to be interrupted and resume operation. The core of the operating system manages the process through the PCB, and the PCB is generally memory-resident, especially the scheduling information must be memory-resident.

There are many processes in an operating system that correspond to different or identical programs and compete for the resources of the system. Process management involves process control, queue management, and process scheduling

The life of a process begins when it is created until it is undone at the end of the task, and it undergoes various state transitions, all under the control of the operating system. The operating system provides basic operations on a process, also known as primitives. These primitives include creation primitives, blocking primitives, termination primitives, priority primitives, and dispatch primitives

Process scheduling is processor scheduling, and its main function is to determine when to assign a processor and to which process. In a time-sharing system, there is generally a definite unit of time (time slice). When a process runs out of a unit of time, process scheduling occurs, that is, the running process changes its state and moves to the tail of the ready queue, and then the first process of the ready queue is taken out by the scheduling primitive and put into operation

There are basically two types of process scheduling methods: non-deprivation scheduling and deprivation scheduling. The so-called non-deprivation scheduling means that once a job or process takes possession of the processor, other processes cannot take the processor away from the process; Conversely, if another process can take the processor away from that process, it is a deprivation of scheduling

The algorithm of process scheduling adopts the strategy of serving the system goal, and for different systems and system goals, different scheduling algorithms are often used, such as first-come-first-served, priority scheduling, and rotation method