Hello all,

Last time i was RAM-cleaning a VM linux server by kill -9 bunch of processes, then i was curious to know how much RAM is available.
Naturally, i thinked of top command:

[hichame@server app]$ top
top - 16:16:59 up 19 days, 2:05, 2 users, load average: 0.00, 0.00, 0.00
Tasks: 186 total, 1 running, 185 sleeping, 0 stopped, 0 zombie
Cpu(s): 11.4%us, 1.4%sy, 0.0%ni, 86.8%id, 0.3%wa, 0.0%hi, 0.0%si, 0.0%st
Mem: 16336460k total, 11442068k used, 4894392k free, 516964k buffers
Swap: 0k total, 0k used, 0k free, 8449812k cached

PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
10639 hichame 20 0 19288 1292 916 R 1.9 0.0 0:00.01 top
1 root 20 0 21444 1224 888 S 0.0 0.0 0:01.49 init
.......

Naturally, i screamed WTF!!! 11442068k of 16336460k is used, near 70% of all my beautiful RAM is used after my wonderfull RAM-cleaning.

Calm down and let’s focus on this line Mem: 16336460k total, 11442068k used, 4894392k free, 516964k buffers and get some help with free linux command :

[hichame@server app]$ free
total used free shared buffers cached
Mem: 16336460 11442068 4894392 0 516964 8449812
-/+ buffers/cache: 2475292 13861168
Swap: 0 0 0


Ahaa, the real available RAM is 13861168 ^_^

If you want more information about free output command checkout this link

Hope this post helps.

Hichame