Linux free Command- Unix System Memory Size Information, cmd Example

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Topic

What is Linux free Command?

Explanation

free COMMAND:
     free command displays information about free and used memory on the system.

SYNTAX:
  The Syntax is
     free [options] [-V]

OPTIONS:

- b	Prints the memory information in bytes.
- k	Prints the memory information in kilo-bytes.
- m	Prints the memory information in mega-bytes.
- s delay	Prints the output continously. Type the delay time to print the output continously.
- t	prints a line containing totals.

EXAMPLE:

To Print the memory size information:

free

              total    used    free   shared  buffers  cached
Mem:          223740   219492   4248     0      3756     73212
-/+ buffers/cache: 142524   81216
Swap:       1052216    66732   985484

The free command displays all the memory information of the system like total memory used and free memory.

To Print memory information from file:

cat /proc/meminfo

MemTotal:         223740 kB
MemFree:            8512 kB
Buffers:            4432 kB
Cached:            67860 kB
SwapCached:        15032 kB
Active:           172484 kB
Inactive:          20168 kB
HighTotal:             0 kB
HighFree:              0 kB
LowTotal:         223740 kB
LowFree:            8512 kB
SwapTotal:       1052216 kB
SwapFree:         985488 kB
Dirty:                52 kB
Writeback:             0 kB
Mapped:           166064 kB
Slab:              14860 kB
Committed_AS:     541000 kB
PageTables:         3260 kB
VmallocTotal:     794616 kB
VmallocUsed:        3056 kB
VmallocChunk:     791084 kB
HugePages_Total:       0
HugePages_Free:        0
Hugepagesize:       4096 kB

The above command prints the memory information of the system.

free Linux Commands