Determing Free RAM on OpenVZ

From OCS Support Wiki

Introduction

OpenVZ uses a shared kernel approach and therefore it is not possible to use tools like top or free to see how much RAM you have available. Instead, you'll see values that relate to the entire server.

Using the openvzmemory Script

We have made available a script that shows you how much RAM you are using on your VDS. Simply run these commands to install it:

cd /usr/local/bin
wget http://www.ocssolutions.com/scripts/openvzmemory
chmod +x openvzmemory

Now you can type openvzmemory to see how much memory you are using.