Page File

The Windows operating system supplements the memory you have on board by using what’s called a page file. This file is a portion of the hard drive set aside for “virtual memory.” By taking some of the memory requirements and using the hard drive, you are able to run more processes and programs within the memory limitations of your system. If your computer starts to run low on resources, it will move data out of memory and into the paging file. 

While this system compensates for many memory issues, it still suffers its fair share of page file errors. You may see errors indicating that your system lacks as a properly sized paging file. Instructions within the warning dialogue will tell you to either use the virtual memory in the Control Panel to create a paging file, or increase the size of your paging file.

Paging file errors occur for a variety of reasons. Oftentimes, the size of the file is too small to compensate for the memory demands the system is making. Windows requires enough space in the paging file to swap out code and data to and from physical memory to the paging file. If not enough space is allocated, page file errors and out of memory errors occur.

Windows will automatically set a default minimum paging file size on your behalf. This generally equals the total amount of your RAM plus 300 MB. On top of this, the maximum default size is set to three times the amount of RAM. For example, if your system has 512MB RAM, the minimum page file size will equal 812MB and the maximum will be 1536MB.

These settings are easily adjustable, especially when encountering low virtual memory errors. To increase the page file size, click the Start button, Control Panel, and either the Advanced tab if you have Windows XP or the Advanced System Settings link if you have Windows Vista. Now choose Performance, then Settings, next Advanced, and finally Virtual Memory. To make adjustments, click on the Change button.

Even when systems demands on physical memory are relatively low, Windows continues to use virtual memory and page files. Systems with larger amounts of physical RAM won’t need page files as large as those relying on smaller amounts of RAM.  In general, when calculating the page file size, allow about one and a half times the amount of physical memory installed. For instances, if you have 512 MB of RAM on your PC, a paging file size of 768 is a good starting point.
 
When your hard drive fills up, you will likely find yourself with a variety of errors including both page file errors and virtual memory errors. To overcome these problems, you will need to clear out your temporary internet files and temporary files as well as defragment your hard disk to free up additional space on your hard drive. If the hard drive has plenty of space to spare, increase the page file size by going back into the Performance Options area.