In the Windows operating system, system resources are allocated in units of "processes". A process is a running activity of a computer program on a certain data set. It is the basic unit of resource allocation and scheduling in the system and the basis of the operating system structure.
The operating environment of this tutorial: Windows 7 system, Dell G3 computer.
In a multiprogramming system, the Windows operating system allocates resources in "process" as the basic unit.
The process was first introduced in the early 1960s by MIT's MULTICS system and IBM's CTSS/360 system.
A process is a running activity of a program in a computer on a certain data set. It is the basic unit of resource allocation and scheduling in the system and the basis of the operating system structure. It can apply for and own system resources. It is a dynamic concept and an active entity. It is not just the code of the program, but also the current activity, represented by the value of the program counter and the contents of the processing registers.
The concept of process has two main points: First, the process is an entity. Each process has its own address space, which generally includes a text region, a data region, and a stack region. The text area stores the code executed by the processor; the data area stores variables and dynamically allocated memory used during process execution; and the stack area stores instructions and local variables for active procedure calls. Second, a process is an "executing program." A program is an inanimate entity. Only when the processor gives life to the program (executed by the operating system) can it become an active entity. We call it a process. [3]
Process is the most basic and important concept in the operating system. It is a concept introduced after the emergence of multi-programming systems in order to describe the dynamic conditions within the system and describe the activity rules of each program within the system. All multi-programming operating systems are based on processes.
A computer system process includes (or "owns") the following data:
A memory image of the program's executable machine code. The allocated memory (usually a region of virtual memory). The contents of memory include runnable code, process-specific data (input, output), call stack, and stack (used to save data generated mid-run during operations). Operating system descriptors of resources allocated to the process, such as file descriptors (Unix terminology) or file handles (Windows), data sources, and data terminals. Security features, such as the process owner and the process's permission set (the operations that are allowed). Processor state (context), such as register contents, physical memory addressing, etc. When a process is running, state is usually stored in registers and in memory otherwise.
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