Current RAM usage is calculated by adding Physical RAM usage + Page File usage. The Page File is a large file on disk that the operating system will begin to utilize as Virtual RAM when Physical RAM runs low. Due to the mechanical nature of disk I/O, this can cause your application (or the entire VPS) to freeze/slow down while Windows works to expand the Page File or retrieve data that should otherwise be stored in RAM.

Before checking your RAM usage you may need to increase your Command Prompt window's buffer size so that you can view all of the systeminfo data that is output to that window.  After opening the CMD window right-click the CMD icon in the upper-left of the window then select Properties.  Input your settings on the Layout tab.
We suggest using the following values for your CMD window sizes:
Screen Buffer Size: Width 120, Height 600 / Window Size: Width 120, Height 30

To check RAM usage: 

• Open a CMD window by clicking Start > Run...
• In the Run box type "cmd", then click OK (A command prompt window will open)

1. In the command prompt window type "systeminfo", then press ENTER

The command will output your VPS' current system information. Look for the following lines near the top:

*This VPS has 512 MB of RAM. It is reflecting 511 MB because 0 is the first increment when your RAM is counted by "systeminfo".

In a Windows Server 2008 R2 VPS the "Page File" values will be replaced by "Virtual Memory" values.

Keep in mind Windows will always use some amount of swap, but anything more than 250 MB will begin to degrade performance.

We use this formula to calculate VPS Total RAM usage:
Total RAM usage = (Total Physical Memory - Available Physical Memory) + (Page File In Use - 250)

In the above case, VPS Total RAM usage is:
(511 - 166) + (375 - 250) = 470 MB of Total RAM used (in a 512 MB Physical RAM subscription)

You should always be sure to have 80-100 MB of Physical RAM over your Total RAM usage.

If your Total RAM usage is above subscribed Physical RAM then it is likely this is causing your application to hang or crash. Try reducing RAM usage or add more Physical RAM to your VPS subscription. Keep in mind that virtually everything you do will use RAM, especially using the Internet Explorer web browser.