Setting Application Priority

If you’re running several applications at a time and your most critical one fails to complete because it is getting interrupted by other processes you also don’t want to terminate, it’s possible you can cure the problem by resetting the priority Windows XP is giving to your application for CPU time. However, as a general rule, the best thing to do is simply to drop other applications that aren’t absolutely critical. By using this technique, you are risking putting the system into a loop you may not be able to recover from easily, if at all, since your application may suddenly find itself in a dead heat with system processes XP needs to keep running.

Generally, system code inside each application assigns a “CPU priority” that XP uses when running the application. This technique will let you override that temporarily, i.e., it will work until you reboot or restart XP.

To do so, simply call up Windows Task Manager by using Ctrl-Alt-Delete. Click on the Processes tab. Find the application whose priorities you want to change on the list displayed. (The name is generally the same as the “.exe” file that is the heart of your application. In the example shown, Outlook is “outlook.exe”.) Right-click on the process name.


On the resulting menu that pops up, scroll down to “Set Priority”. (Here’s where you need to be careful.) Pick a priority that you want to set. The dot shows you where the application’s CPU priority currently is.

Within the operating system, priorities exist in a range from 0 to 31. A Normal priority rating assigns a value of 8. Realtime gives an application a priority of 24; and, as such, is the most dangerous assignment to use since it can interfere with Windows XP’s kernel or other operating system processes. (You may not be able to get out the consequences of setting an application this high without rebooting, causing you to lose some data.) High assigns a priority of 13, and Low a value of 4. Abovenormal assigns a value of 13, and Belownormal assigns a value of 6.

One way to get a look at what the reassignment has done to CPU usage is to use Windows Task Manager’s Performance/CPU Monitor tool to gauge CPU usage before and after reassigning CPU priority. The biggest way you’ll know what it’s done is by whether or not the application is now performing more in the way you wanted it to and whether or not your computer has locked up.

Click here to return to Managing Your Applications within XP.