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Question

High CPU usage

Sep 1, 2011 8:35AM PDT

Recently i have had very high cpu usage on my mac with very little running. Right now activity monitor says the system is using 67% and i am only running crome and activity monitor. I have a newer macbook pro maybe a month or two old. It is running lion. I have run some legit spyware/malware scans they didn't find anything but im willing to try another program. Also in safe mode the CPU usage is normal. I would like to avoid reinstalling although i do have a lion disk to do so with. Thank you in advance for any help.

Discussion is locked

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Clarification Request
So if you use Activity Monitor
Sep 1, 2011 10:32AM PDT

So if you use Activity Monitor to list processes in order of CPU usage, which one(s) are using the most CPU time?

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Activity monitor
Sep 1, 2011 2:35PM PDT

Well it has actually been getting better and then way worse and it seems to be random right now it is fine but an hour ago the kernal processes were using like 200% and some crazy amount of memory. So i guess that would account for all the system usage. Do you know what could be making this randomly happen?

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A lot of different things
Sep 1, 2011 11:06PM PDT

A lot of different things could generate kernel_task activity.

I am curious about these "legit" spyware scans you ran, since there's really no spyware/malware for Mac OS X, which would make these allegedly "legit" scans somewhat suspect on their face.

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Scanners
Sep 2, 2011 2:17AM PDT

Well I got the scanners from a forum where someone was having issues and they were like computer cleaners too not just malware scanners one was called mac keeper the other was ClamxAV. Also the problem was there before i ran any programs. Also Sometimes when i put it to sleep and wake it up the kernal processes are low and everything works fine, but i would like a concrete solution instead of spend 10 minutes everytime i want to use my computer.

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Well
Sep 2, 2011 10:43AM PDT

Well, from a cursory glance, Mac Keeper is a scam program. One of those that will do a bunch of really simple things you could have done yourself, only for the low low price of $50 or whatever it is they want for it. ClamXAV isn't a scam, but it also doesn't check for malware last I checked. It's an open source AV scanner, and while I applaud the effort, it's still not even in the same league as commercial scanners.

The fact that safe boot works without issue tends to point the finger at some program starting at login. So go to the user account section of system preferences, then hit the login items tab and see what there is. Then google each one along with "kernel_task" (make sure that's with two e's on kernel) and see what turns up.

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Power supply
Sep 2, 2011 2:15PM PDT

I have tracked the problem down to the power supply because when ever the computer is unplugged from the power supply the CPU goes crazy and kernel tasks go to like 270%. However when connected it runs fine.

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No
Sep 2, 2011 11:11PM PDT

No, when you disconnect the ac adapter the OS defaults to a lower power operating mode. So, all you've found is a triggering event that sounds a lot like some sort of OS corruption. At this point I'd say you've run out of options to avoid reinstalling the OS.

Once you reinstall the OS, only install the barest of minimum apps you need for 2-3 days. If you can make due with Safari for a couple of days, even better. Then remember that Spotlight will be indexing your drive for a day or two so if CPU use seems a little high early on that's normal. After 2-3 days, if the problem is persisting, and you've only installed the barest minimum of apps, the problem either exists with one of those apps or there's an issue with the SMC that is much deeper than a corrupted state. You'd need to take your system in for a diagnostic.

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Resetting the System Management Controller
Sep 2, 2011 2:56AM PDT

so after figuring out that the power adapter not being plugged in the mac is cause the problem i reset the SMC and it didn't help.

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Answer
I had this problem and it turned out...
Sep 2, 2011 8:47AM PDT

I had this problem and it was driving me crazy. What solved it was quitting Firefox and using Google Crome.

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I dont even have firefox
Sep 2, 2011 2:14PM PDT
I dont have firefox I uninstalled it because I thought that was the issue but that didn't do anything.