Manual: free

FREE(1)							User Commands						     FREE(1)

NAME
       free - Display amount of free and used memory in the system

SYNOPSIS
       free [options]

DESCRIPTION
       free  displays  the  total amount of free and used physical and swap memory in the system, as well as the buffers and
       caches used by the kernel. The information is gathered by parsing /proc/meminfo. The displayed columns are:

       total  Total usable memory (MemTotal and SwapTotal in /proc/meminfo). This includes the physical and swap memory	 mi‐
	      nus a few reserved bits and kernel binary code.

       used   Used or unavailable memory (calculated as total - available)

       free   Unused memory (MemFree and SwapFree in /proc/meminfo)

       shared Memory used (mostly) by tmpfs (Shmem in /proc/meminfo)

       buffers
	      Memory used by kernel buffers (Buffers in /proc/meminfo)

       cache  Memory used by the page cache and slabs (Cached and SReclaimable in /proc/meminfo)

       buff/cache
	      Sum of buffers and cache

       available
	      Estimation  of  how  much memory is available for starting new applications, without swapping. Unlike the data
	      provided by the cache or free fields, this field takes into account page cache  and  also	 that  not  all	 re‐
	      claimable	 memory	 slabs will be reclaimed due to items being in use (MemAvailable in /proc/meminfo, available
	      on kernels 3.14, emulated on kernels 2.6.27+, otherwise the same as free)

OPTIONS
       -b, --bytes
	      Display the amount of memory in bytes.

       -k, --kibi
	      Display the amount of memory in kibibytes.  This is the default.

       -m, --mebi
	      Display the amount of memory in mebibytes.

       -g, --gibi
	      Display the amount of memory in gibibytes.

       --tebi Display the amount of memory in tebibytes.

       --pebi Display the amount of memory in pebibytes.

       --kilo Display the amount of memory in kilobytes. Implies --si.

       --mega Display the amount of memory in megabytes. Implies --si.

       --giga Display the amount of memory in gigabytes. Implies --si.

       --tera Display the amount of memory in terabytes. Implies --si.

       --peta Display the amount of memory in petabytes. Implies --si.

       -h, --human
	      Show all output fields automatically scaled to shortest three digit unit and display the units of	 print	out.
	      Following units are used.

		B = bytes
		Ki = kibibyte
		Mi = mebibyte
		Gi = gibibyte
		Ti = tebibyte
		Pi = pebibyte

	      If  unit is missing, and you have exbibyte of RAM or swap, the number is in tebibytes and columns might not be
	      aligned with header.

       -w, --wide
	      Switch to the wide mode. The wide mode produces lines longer than 80 characters.	In  this  mode	buffers	 and
	      cache are reported in two separate columns.

       -c, --count count
	      Display the result count times.  Requires the -s option.

       -l, --lohi
	      Show detailed low and high memory statistics.

       -L, --line
	      Show output on a single line, often used with the -s option to show memory statistics repeatedly.

       -s, --seconds delay
	      Continuously  display the result delay  seconds apart.  You may actually specify any floating point number for
	      delay using either . or , for decimal point.  usleep(3) is used for microsecond resolution delay times.

       --si   Use kilo, mega, giga etc (power of 1000) instead of kibi, mebi, gibi (power of 1024).

       -t, --total
	      Display a line showing the column totals.

       -v, --committed
	      Display a line showing the memory commit limit and amount of committed/uncommitted memory. The total column on
	      this line will display the memory commit limit.	This line is relevant if memory overcommit is disabled.

       --help Print help.

       -V, --version
	      Display version information.

FILES
       /proc/meminfo
	      memory information

BUGS
       The value for the shared column is not available from kernels before 2.6.32 and is displayed as zero.

       Please send bug reports to
	      procps@freelists.org

SEE ALSO
       ps(1), slabtop(1), top(1), vmstat(8).

procps-ng						 2023-05-02						     FREE(1)