How to Determine Virtual Memory

By Deborah Lee Soltesz

"Virtual memory" is a memory management technique used by Windows to assign memory to running software. Windows uses both physical memory and files stored on the hard drive, called "page files," to provide the assigned memory to running software. Physical memory is a limited resource determined by the amount of random access memory (RAM) installed in the computer. When physical memory is full, Windows automatically frees memory by moving data to the page file. Page file size is typically set to to be 1.5 to 4 times the amount of installed RAM.

Virtual Memory Usage

Step 1

Right-click on the task bar. Select "Task Manager" from the menu. The "Windows Task Manager" window opens.

Step 2

Click on the Processes tab.

Step 3

Open View | Select Columns. Add a checkmark to the box next to "Virtual Memory Size." Click "OK." A column labeled "VM Size" is added to the running processes list.

Step 4

Look at the list of running processes. "Mem Usage" is the amount of physical memory used by the process. "VM Size" is the amount of virtual memory assigned to the process.

Step 5

Click on the Performance tab. In the "Commit Charge (K)" box, the "Total" is the total amount virtual memory (RAM and page file usage) in kilobytes in use by the system. In the "Physical Memory (K)," the total amount of RAM in kilobytes used by the system is the "Available" subtracted from the "Total." The page file usage is the difference between the "Commit Charge: Total" and the amount of used RAM.

Virtual Memory Settings

Step 1

Click the Start (or Windows) button on the taskbar and select "Control Panel."

Step 2

Click "System." The "System Properties" window opens. Note the amount of RAM listed under "Computer" on the General tab.

Step 3

Calculate the page file size you need by multiplying the amount of RAM memory by 3.0. If the amount of RAM is expressed in gigabytes (GB), multiply the number by 1024 to convert it to megabytes (MB).

Step 4

Click the Advanced tab.

Step 5

Click the "Settings" button in the "Performance" box. The "Performance Options" window opens.

Step 6

Click the Advanced tab.

Step 7

Click the "Change" button in the "Virtual Memory" box. The "Virtual Memory" window opens.

Step 8

Click the drive letter that has a value defined in the displayed "Paging File Size (MB)" column.

Step 9

Click the "Custom size" radio button. Enter the page file size you calculated for both the "Initial Size (MB)" and the "Maximum size (MB)."

Step 10

Click the "Set" button to apply the new setting.

Step 11

Click the "OK" button on each open window and close the windows.

Tips & Warnings

  • If you get a "Windows virtual memory is too low" error message, set the virtual memory paging file size to a value higher than the old setting.
  • Setting Virtual Memory settings to "No paging file" on all disks may have a detrimental effect on performance. Make certain at least one drive has at least the minimum allowed paging file size set.