In Linux, free is a built-in command to view the memory usage status. It can display the usage of system physical memory, virtual memory (swap swap partition), shared memory and system cache. Syntax "free [option]"; the output of the free command is very similar to the memory part of the top command.
Linux free command: Check memory usage status
The free command is used to display the system memory status, including system physical memory and virtual memory (swap swap partition) , shared memory and system cache usage, the output is very similar to the memory part of the top command.
The basic format of the free command is as follows:
# free [选项]
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Table 1 lists the commonly used options of this command and their respective meanings.
Table 1 Free command common options and their meanings
Options
Meaning
##- b
Displays memory usage in Byte (byte).
-k
Displays memory usage in KB. This option is the default option of the free command.
-m
Displays memory usage in MB.
-g
Displays memory usage in GB.
-t
In the final result of the output, output the total amount of memory and swap partition.
-o
Do not display the system buffer column.
-s Interval seconds
Continue to display memory usage according to the specified interval.
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