Finding out total memory usage

Hi,

I have a server box with 16GB ram in it, within the server box there are 3 VMs running with a total allocation of 9GB.

if I add up all the numbers under memory info using vmstat I get 15.8GB so I can say it adds up to 16Gb...

Is there a way to see from the command line how much memory is being allocated to the VMs? Because we seem to have 3GB of RAM missing...

Please take a look at the attached pics, the first one is the master box with 16GB ram but only 13 being used.

The send one shows the ram allocated for the master + the 3 VMs which totals to 13gb.

I want to know where is the extra 3gb gone? How can i figure out where to locate it?

You can see "physical" memory installed, executing from each VM something like this:

dmidecode | grep 'Memory Device$' -A6 | grep Size