free - Display amount of free and used memory in the system
free [-b | -k | -m] [-o] [-s delay ] [-t] [-V]
free displays the total amount of free and used physical and swap memory in the system, as well as the buffers used by the kernel.
The shared memory column should be ignored; it is obsolete.
- -b
- switch displays the amount of memory in bytes; the -k switch (set by default) displays it in kilobytes; the -m switch displays it in megabytes.
- -t
- switch displays a line containing the totals.
- -o
- switch disables the display of a "buffer adjusted" line
- -s
- switch activates continuous polling delay seconds apart.
- You may actually specify any floating point number for delay, usleep(3) is used for microsecond resolution delay times.
[username@hostname~]$ free -m
total used free shared buffers cached
Mem: 48314 45509 2805 0 992 20808
-/+ buffers/cache: 23708 24606
Swap: 3999 264 3735