Recently, some customers often asked why, after installing various environments in Linux, they accidentally found that the memory was not enough. For example, the system's original 80% MB memory was nearly of the memory, and it seems that it was not enough, in fact, this is a feature of Linux memory management.
Linux has excellent memory management features, which are different from Windows. Linux fully considers the system data exchange rate. It uses idle memory to allocate a portion of space for Cache and buffers to increase system speed and reduce consumption.
The Cache (high-speed Cache) is the main Cache of the Linux kernel. Because the access speed of the physical memory is more than 10 times faster than that of the disk, the content in the disk is pre-read into the physical memory, then, the direct access to the disk is changed to access to the physical memory. Reduces read/write (I/O) operations on disks and improves system efficiency.
The following is a Linux virtual host server Probe:
This site provides a Linux Server probe download: Click to download
How does one view the usage of physical memory?
Line 1: physical memory (physical memory usage + Linux memory mechanism buffer)
It refers to the total amount of physical memory occupied by the server, including physical usage + Cache + Buffers.
Row 2: separately display the System Buffer Capacity (that is, the Linux memory mechanism buffer)
Row 3: actual memory usage of the system (if no buffer is used, the actually occupied memory is used)
Row 4: SWAP area (similar to Windows virtual memory)