Virtual memory, also known as a page file or swap file, is a file on your hard drive (C:\pagefile.sys by default) that Windows and applications use in addition to physical memory (RAM) as needed.
Optimizing your page file when you're running low on RAM is always a good idea. When all physical RAM in a computer is in use, Windows starts using the hard disk as if it were additional RAM. This is why we have a Pagefile (also called the swap file). Because RAM memory is a lot more faster than the hard disk, whenever the computer begins to use the Pagefile to relieve memory pressure, we begin to experience a drastic performance degradation.
One of the most effective things you can do to improve performance is ensure that there is enough RAM available to avoid frequent paging (swapping) of memory contents between disk and RAM.
This means that the actual limit on the memory used by all applications is the amount of RAM installed plus the maximum size of the Pagefile.
How much swap space do you need?
That depends the amount of RAM you have and the programs you use. The rule of the thumb is 1.5 times the amount of system memory(RAM).
In Windows XP:
1. Click Start, and then click Control Panel.
2. Click Performance and Maintenance, and then click System.
3. On the Advanced tab, under Performance, click Settings.
4. On the Advanced tab, under Virtual memory, click Change.
5.Under Drive [Volume Label], click the drive that contains the paging file that you want to change.
6. Under Paging file size for selected drive, click to Custom size check box. You can enter the amount of memory you would like to reserve for Virtual memory by entering the initial and maximum size.
7. Click Set.
When you are prompted to restart the computer, click Yes.
If not Restart the Computer manually.
Special Note: You should choose the same amount for the initial size and maximum size. This will Stop your CPU from constantly changing the paging file.
Note: To stop your CPU from constantly changing the paging file, set the initial and maximum size to the same value. For example, 500 and 500. The value should be at least 1.5 times more than your physical RAM. If your computer has 512MB of RAM increase the virtual memory paging file to 1.5*512= 768
Remember to choose the drive you would like to use to increase the virtual memory. In most cases it usually your C: Drive. You can set the initial size and maximum size after clicking the Custom size check box.Remember its better to keep the Virtual memory values the same.Also having enough available space is absolutely necessary for your virtual memory and RAM to function properly.
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