Four basic characteristics of processes

Process

A process (Process) is a running activity of a program in a computer on a certain data collection. It is the basic unit for resource allocation and scheduling in the system and the basis of the operating system structure. In the early process-oriented computer architecture, the process was the basic execution entity of the program; in the contemporary thread-oriented computer architecture, the process is the container of threads. A program is a description of instructions, data and their organization, and a process is the entity of the program.

Four basic characteristics of the process

Dynamicity: The essence of the process is the execution of a program in a multi-program system. The process is dynamically generated and dynamically destroyed. of.

Concurrency: Any process can execute concurrently with other processes

Independence: A process is a basic unit that can run independently, and it is also an independent unit for system allocation and scheduling;

Asynchronicity: Due to the mutual constraints between processes, the process has intermittent execution, that is, the processes advance at independent and unpredictable speeds

Structural features: The process consists of programs, It consists of three parts: data and process control blocks.

Multiple different processes can contain the same program: a program constitutes different processes in different data sets and can obtain different results; but during execution, the program cannot change.

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