Print number of mb of free ram

free -m | awk '/buffer/ {print $4}'
Here we instead show a more real figure for how much free RAM you have when taking into consideration buffers that can be freed if needed. Unix machines leave data in memory but marked it free to overwrite, so using the first line from the "free" command will mostly give you back a reading showing you are almost out of memory, but in fact you are not, as the system can free up memory as soon as it is needed. I just noticed the free command is not on my OpenBSD box.
Sample Output
4920

3
By: DaveQB
2010-06-27 23:30:27

2 Alternatives + Submit Alt

What Others Think

The free manpage says : If the -o option is not specified, free subtracts buffer memory from the used memory and adds it to the free memory reported. Unix software on unix machines are often made by smart people. Just read the man page.
CodSpirit · 433 weeks and 6 days ago
CodSpirit, I like your thinking, but not having the desired effect here on a CentOS 5.3 box: root@om012234 ~ $ free -m total used free shared buffers cached Mem: 8004 5660 2343 0 68 1639 -/+ buffers/cache: 3953 4050 Swap: 996 0 995 root@om012234 ~ $ free -mo total used free shared buffers cached Mem: 8004 5647 2356 0 68 1639 Swap: 996 0 995 3953 is the figure we are after. Omitting the -o switch gives us that.
DaveQB · 414 weeks and 4 days ago
Rather 4050 for RAM free. 3953 is RAM used.
DaveQB · 414 weeks and 4 days ago

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