The memory information displayed by the Linux free command

Linuxfree Command memory allocation information

[[Email protected]~]# free-m

Total used free shared buffers Cached

mem:32099 31909 189 1 100 28679

-/+ buffers/cache:3129 28969

swap:15999 0 15999

the output from the second line is the operating system memory usage.

The output from the third row is the memory usage of the application.

physical Memory = [mem:used] + [Mem:free]

physical Memory = [-/+ buffers/cache: used] + [-/+ buffers/cache Free]

[Mem:total] Total Physical Memory

[Mem:used] indicates the memory used

[Mem:free] indicates the remaining memory

[Mem:shared] memory shared between processes

[Mem:buffers] represents the memory used, no buffer used

[Mem:cached] represents the memory used, the cache is not used

[-/+buffers/cache: used] represents the memory used, the buffer and the cache that have been used

[-/+buffers/cache: used]= [mem:used] - [mem:buffers+ mem:cached]

[-/+buffers/cache: free] represents the remaining (usable) buffer and cache( which represents the memory used, no buffer used , and Cache + remaining available memory [Mem:free])

[-/+buffers/cache: free]=[mem:free] +[mem:buffers] + [mem:cached]

generally, if [ -/+ Buffers/cache:free] is large, it indicates that there is more memory left.

[Mem:buffers] and the [mem:cached] is also a reflection the remaining Buffer and the cache,.

a picture of the memory allocation shown by the free command

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How to determine the state of memory usage?

Note [Mem:free] size does not reflect the actual use of memory.

1. View -/+ buffers/cache:free , if the value is very small, and the swap is used more, that means the memory is not enough.

2. View mem:buffers mem:cached , ibid.

Bufers and cached can be quickly recycled.

all output values of the free command are read from the/proc/meminfo .

This article is from the "helo" blog, make sure to keep this source http://487510.blog.51cto.com/477510/1663596

The memory information displayed by the Linux free command