What is running memory

Running memory refers to the memory required when a program is running; the size of the running memory directly determines how many programs the system can run. The larger the running memory, the faster the system can run programs. Running memory can be classified according to its usage: available physical memory, free physical memory, cached physical memory, spare physical memory, modified physical memory, used physical memory, etc.

The operating environment of this tutorial: Windows 7 system, Dell G3 computer.

Running memory, also called main memory, refers to the memory required when the program is running. It can only temporarily store data and is used to exchange cache data with the CPU. It generally refers to random access memory (Random Access Memory, RAM).

The size of the running memory directly determines how many programs the system can run. The larger the running memory, the faster the system runs programs. The development of memory is closely related to processor technology and system optimization. If the processor performance itself cannot keep up, or the system optimization is not effective, even if it is equipped with larger memory, it will be a waste of resources.

When the computer is running, the computer's main memory can be classified according to its usage:

Available (Available) physical memory: memory that can be immediately allocated for use by programs. Includes:

Free physical memory: completely unused, the content is all 0

Cached physical memory

Standby physical memory: operation The system pre-loads the memory occupied by the hard disk data that may be used. It has not been used by the user process, so it can be discarded at any time and re-initialized to 0.

Modified (modified) physical memory: has been modified The memory used for caching can be written back to the hard disk file (not the paging file) at any time and then reused. Due to hard disk I/O, modified physical memory cannot be counted toward free physical memory.

Used (used) physical memory: memory that has been used by the process.

The physical memory used by the user process, that is, the working set (Working set). The Working Set contains memory that may be shared by other programs, such as DLLs. Therefore, the total working set of all processes may be larger than the actual used physical memory. Private Bytes is the virtual address space submitted only by this process, excluding memory shared by other processes. Virtual Byte is the entire virtual address space occupied by the entire process. In 32-bit Windows user mode, a process can use up to 2GiB, which can be expanded to a maximum of 3GiB by modifying the Boot.ini file. Memory Usage in task manager corresponds to working set, and VM Size corresponds to private bytes.

Physical memory used by the core process

Physical memory used by the paged core process: Physical memory that can be swapped into a paging file and thus can be reclaimed.

Physical memory used by non-paged (Non paged) core processes: memory that cannot be swapped to paging files and always remains in physical memory

Physical memory reserved by hardware Memory: Memory occupied by the GPU core or other peripheral hardware in the CPU and not used by the operating system.

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