This is a great example of things we geeks take for granted that aren’t always obvious to the rest of the world.
I mean, really, a process that regularly takes up 99% of your CPU’s resources must be a bad thing, right?
Nope, not at all. Just the opposite, in fact.
Become a Patron of Ask Leo! and go ad-free!
System Idle Process
Let me show you what we’re talking about.
Right-click on the clock in the taskbar, and click on Task Manager. Click on More details, if present, and then on the Details tab. Now click on the CPU column heading to sort by CPU Usage (click again to reverse the sort order if all you see are zeros in that column), you’ll typically see something like this:
Something called “System Idle Process” is taking up a full 95% of my CPU’s resources.
No such thing as doing nothing
Most computers never really do nothing. When the computer is on, the CPU is running, and it must do something even if “something” is waiting for something real to do.
Think of it as your computer twiddling its virtual thumbs, waiting for something more important to do. The computer is doing something (virtual thumb twiddling), but we wouldn’t call it doing anything useful.
That’s called being idle.
“System Idle Process” is the software that runs when the computer has absolutely nothing better to do.
It has the lowest possible priority and uses as few resources as possible, so that if anything at all comes along for the CPU to work on, it can. When there’s nothing left to do, back to idle it goes.
Having the System Idle Process use 95% of your CPU is a good thing. It means that 95% is readily available should there be any real work to do.
If you found this article helpful, I'm sure you'll also love Confident Computing! My weekly email newsletter is full of articles that help you solve problems, stay safe, and give you more confidence with technology. Subscribe now and I'll see you there soon,