centos man page for 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 ker-
       nel. The information is gathered by parsing /proc/meminfo. The displayed columns are:

       total  Total installed memory (MemTotal and SwapTotal in /proc/meminfo)

       used   Used memory (calculated as total - free)

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

       shared Memory used (mostly) by tmpfs (Shmem in /proc/meminfo, available on kernels 2.6.32, displayed as zero if not available)

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

       cached Memory used by the page cache  (calculated as Cached - Shmem in /proc/meminfo - the Cached value is actually the sum of  page  cache
	      and tmpfs memory)

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

       -k, --kilo
	      Display the amount of memory in kilobytes.  This is the default.

       -m, --mega
	      Display the amount of memory in megabytes.

       -g, --giga
	      Display the amount of memory in gigabytes.

       --tera Display the amount of memory in terabytes.

       -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
		K = kilos
		M = megas
		G = gigas
		T = teras

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

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

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

       -o, --old
	      Display the output in old format, the only difference being this option will disable the display of the "buffer adjusted" line.

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

       --si   Use power of 1000 not 1024.

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

       --help Print help.

       -V, --version
	      Display version information.

FILES
       /proc/meminfo
	      memory information

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

AUTHORS
       Written by Brian Edmonds.

REPORTING BUGS
       Please send bug reports to <procps@freelists.org>

procps-ng							  September 2011							   FREE(1)