Summary: Occasionally one program will use up all of your computers processing resources. Using process explorer it's easy to figure out which program that is.
My machine is slower than molasses in the winter time, and I suspect that one or more programs are simply using up all available CPU time. How do I tell which ones they might be so that I can turn them off, or whatever?
•
Yep, that sounds slow.
Actually it happens to me from time to time as well. A program will decide it has something very very important to do, and decides to use your computer and all of its processing power to do it.
The good news is it's easy to find out which program that might be.
•
All evidence to the contrary, computers can really only do one thing at a time. OK, a dual core or dual processor machine can do exactly two things at a time, a quad core can do 4, and so on. But a single CPU can do exactly only one thing at a time. It just switches between them all really, really quickly.
So when one program needs all of the CPU's attention, other programs that need the CPU might not get enough time to do their work. That typically results in a very slow system, from a user's perspective.
We can use task manager to figure out who the culprit is, but I very much prefer the free download Process Explorer. Download and run it, and you should see something very much like this:
The default display shows all he tasks running on your computer, in hierarchical order, meaning that if program A was the one that started program B, then program B appears indented beneath program A. That can be helpful for other reasons, but not what we want here.
Click on the column labeled CPU, and Process Explorer will sort the processes by CPU usage. The processes using the most CPU will be listed at the top:
Here you can see that when I took this image my CPU was actually 68% idle; in other words the it was doing nothing at all two thirds of the time. The next highest program on the list was SnagIt, the screen capture program I use, using about 14% of CPU, followed by Windows Explorer, Trillian, and others in decreasing order.
Here's another example after starting up an audio processing utility:
Here that program is using about 50% of my CPU's available processing power.
In many reports I get it's a program called "svchost.exe" that has people concerned and mystified. I've talked about svchost, and why there might be more than one copy running on your machine before. As of this writing there's a common problem that people are experiencing involving the Windows Update service causing its instance of svchost to use all available CPU. If right click on the svchost that appears at the top of Process Explorer's CPU usage list, click on Properties, and then click on the Services tab, you'll see all the system services that instance of svchost is providing:
You'll see that this is the instance of svchost that handles Automatic Updates on my machine, and that I have the option of stopping that service right there.
Regardless of what's actually causing your CPU usage problems, if you're having any, Process Explorer is a quick way to not only identify the culprit, but as its name implies, Explore some of the interesting information about the processes running on your machine.
Related:
-
Ask Leo! - How do I find out who's using all my memory?
-
Ask Leo! - What is svchost, and why is there more than one copy running?
-
Ask Leo! - How do I download Process Explorer?
Article C3003 - April 24, 2007
-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1
It jumps around because which programs are using the CPU changes. Every second
process explorer updates the list to be in the current most-used CPU usage
order. You can adjust the update speed if you like using the View->Update Speed
menu item. Or you can click on the CPU column again to get things sorted by
name.
Leo
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.6 (MingW32)
iD8DBQFGNCUCCMEe9B/8oqERAmdlAJ9Byx+Sdt8ZRQKedWBwfxViJgIhEgCdHl9s
Posted by: Leo A. Notenboom at April 28, 2007 9:54 PMgoxdy1YmSopHu7B+Rtg85/Y=
=ttgT
-----END PGP SIGNATURE-----
-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1
Joseph: a garage mechanic can't fix a car without seeing it. There are SO many
reasons that a program might suck up all the CPU there is no one, single
solution. All that mechanic-at-a-distance can do is provide you with some tools
to help diagnose the problem yourself.
What this article does is provide a way for you to gather perhaps the most
important clue: to figure out what program is taking all the CPU. That could be
any of 100's programs, and the next steps to fixing the problem will depend on
what program that is.
Leo
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.6 (MingW32)
iD8DBQFGNCfrCMEe9B/8oqERAkrlAJ498imjoCKcURmnSbF5JLISjPJa8wCfRT6N
Posted by: Leo A. Notenboom at April 28, 2007 10:07 PMY7rLEfFoojMWZwdmfqPaf40=
=1bOG
-----END PGP SIGNATURE-----
Got that program after reading about on your newsletter and I find it a great boone to getting info on what is going on and where all the named processes are.Thanks for great leads.
Posted by: Bill at April 29, 2007 2:28 PMBill
Very useful and easy to understand. I've printed this article for myself because I need the hard copy of multiple-step instructions right in front of me as I'm doing whatever. But as with so many Web pages, the meat of the article printed in such tiny print that I'm having a devil of a time reading it. My 8 1/2 x 11 page is full, I didn't have to shrink it to fit, and under my View category, I've clicked on the Largest type size, but none of this helps the pages to print the type in a larger size. This is only for Web pages and email. Word and Excel documents print whatever size I tell them to print. Suggestions, please. My printer is an hp 7660 and I know how to change things in the printer only through the pages I can reach when I click on the Print button. Thanks for any help you can give me.
Posted by: Bombay Granny at April 29, 2007 4:04 PM-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1
What browser are you using?
Leo
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.6 (MingW32)
iD8DBQFGNkOtCMEe9B/8oqERAj1cAJ9IP4qRHbXO011Jk2PZnFAoCBx05wCeP+Bf
Posted by: Leo A. Notenboom at April 30, 2007 12:29 PMTsqR8u0I4gJTQzlR5jTgkzc=
=v18+
-----END PGP SIGNATURE-----
I agree with Leo, Process Explorer is invaluable. So much so that I have it set to run automatically at startup time (minimized to the system tray).
I use PE with the display sorted by process name. This keeps things from jumping around like they do when sorted by cpu usage. It also gets rid of the process tree display which is of no use to me. The only down side to this is that if you have many processes, the one using the most cpu may not fit in the display and you'll have to scroll down to see it.
And, I get rid of the lower half of the display which is also of no use to me. There is button on the toolbar for this - it is referred to as the lower panel.
Click on View -> Select columns. PE is a wealth of information.
Posted by: Michael Horowitz at April 30, 2007 3:11 PMAt Last Leo
Posted by: Peter Robinson at April 30, 2007 5:28 PMThank you I've been Hoping this type of program would pop up.
Now when my computer freezes or slows down I can find out why
Pete
Where do I go to find out what Browser I am using? I am NOT Computer Knowledgeable, so please help me. Some of the programs I want to use do not function and it all depends on what Browser I have.
Posted by: Cheryl at February 29, 2008 6:44 PMWow, this is an amazing problem, found one computer had the update problem, and another has the error from HP's program.
Posted by: Ryan at August 3, 2008 9:01 AMIs there a way to actually specify which program gets to use all of the CPU? When I used a Mac years ago, we were able to designate more memory to the program we used the most. Can Windows Vista or XP do anything like that?
Posted by: Rita at January 22, 2009 6:21 AM