Hack 89. Free command examples

Free command displays all the necessary information about system physical (RAM) and swap memory.

Syntax: free [options]

What is the total RAM on my system?

In the example below, the total physical memory on this system is 1GB. The values displayed below are in KB.

# free
       total   used    free   shared  buffers  cached
Mem: 1034624   1006696 27928  0       174136   615892
-/+ buffers/cache:     216668      817956
Swap:    2031608       0    2031608

What is the total memory on my system including RAM and Swap?

In the following command:

• option m displays the values in MB
• option t displays the “Total” line, which is sum of physical and swap memory values
• option o is to hide the buffers/cache line from the above example.

# free –mto
                  total       used      free     shared    buffers     cached
Mem:          1010        983         27              0         170           601
Swap:          1983            0    1983
Total:          2994        983     2011