What is kernel_task and why is it taking up so much memory?

[LPZ]

Originally Posted by phalgun27

I have both smcFanControl and iStat Pro. The fan speed is 0 rpm in both the apps. I have changed the fan speed in smcFanControl but nothing happened. I guess the exhaust fan is not working.

I don't have OS install disk. I tried to boot holding D key but it didn't work. I even tried connecting ethernet and booting but it didn't work too. Are there any other techniques for doing AHT?

I noticed the kernel_task is above 200% when I am watching movies or using flash and when the Mac is getting hot.

The CPU Temperature was 80-90C (not F)

If the fan is indeed not working then you must fix that immediately. Then see if the other issues are still present.

[phalgun27]

Originally Posted by LPZ

If the fan is indeed not working then you must fix that immediately. Then see if the other issues are still present.

I replaced the fan and it works fine now

[roaddawg45013]

Any help would be appreciated

[gnasher729]

Originally Posted by roaddawg45013

Any help would be appreciated

Help? Very easy. Just relax. Don't worry.

You don't have a clue what kernel_task is there for and what it is doing. Most likely it is doing exactly what it is meant to do.

[GGJstudios]

Originally Posted by roaddawg45013

Any help would be appreciated

Read post #9. Your screenshots look completely normal.

[Weaselboy]

Originally Posted by roaddawg45013

Any help would be appreciated

You are correct. 167% CPU usage on an idle system is not normal. Something is chewing up CPU cycles.

I am assuming from looking at your Dock you have nothing else running and Spotlight is not reindexing.

Have you installed something recently like maybe a driver that could have caused this?

Try a safe mode boot while holding down the shift key. This will prevent any startup items from running. While in safe mode look at Activity Monitor again. If the problem is gone, that tells you it is related to a startup item.

Also, try checking in Console log while this is happening for any error reports that may help you pinpoint the problem.

[roaddawg45013]

Originally Posted by Weaselboy

You are correct. 167% CPU usage on an idle system is not normal. Something is chewing up CPU cycles.

I am assuming from looking at your Dock you have nothing else running and Spotlight is not reindexing.

Have you installed something recently like maybe a driver that could have caused this?

Try a safe mode boot while holding down the shift key. This will prevent any startup items from running. While in safe mode look at Activity Monitor again. If the problem is gone, that tells you it is related to a startup item.

Also, try checking in Console log while this is happening for any error reports that may help you pinpoint the problem.

For some reason I have a long wait for the computer to boot (over 2 min.) and I can't get it to boot in safe mode. In addition, the fans run at 6000rpm's.

[Weaselboy]

Originally Posted by roaddawg45013

For some reason I have a long wait for the computer to boot (over 2 min.) and I can't get it to boot in safe mode. In addition, the fans run at 6000rpm's.

Hmm... dunno why safe mode would not work. Shut off the machine then hold the shift key down when you hear the chime.

Do you see anything odd in Console log when this is going on?

[roaddawg45013]

Originally Posted by Weaselboy

Hmm... dunno why safe mode would not work. Shut off the machine then hold the shift key down when you hear the chime.

Do you see anything odd in Console log when this is going on?

Well...been getting a frustrated!

I thought it was the logic board so I removed it and installed into another 2010 Macbook pro of mine and it works perfect (quick start up and fans running @ 2000 rpm with no kernel problems. Put it back into the other 2010 Macbook Pro and the same thing happens as before, long start up and fans running at 6000 rpms and kernal_task cpu at almost 200%.
I cloned the hard drive (CCC) so they are using the same software.

----------

Originally Posted by Weaselboy

Hmm... dunno why safe mode would not work. Shut off the machine then hold the shift key down when you hear the chime.

Do you see anything odd in Console log when this is going on?

Well...been getting a frustrated!

I thought it was the logic board so I removed it and installed into another 2010 Macbook pro of mine and it works perfect (quick start up and fans running @ 2000 rpm with no kernel problems. Put it back into the other 2010 Macbook Pro and the same thing happens as before, long start up and fans running at 6000 rpms and kernal_task cpu at almost 200%.
I cloned the hard drive (CCC) so they are using the same software.

[Weaselboy]

Originally Posted by roaddawg45013

Well...been getting a frustrated!

I thought it was the logic board so I removed it and installed into another 2010 Macbook pro of mine and it works perfect (quick start up and fans running @ 2000 rpm with no kernel problems. Put it back into the other 2010 Macbook Pro and the same thing happens as before, long start up and fans running at 6000 rpms and kernal_task cpu at almost 200%.

I cloned the hard drive (CCC) so they are using the same software.

Not good. That points away from a software problem and looks like some kind of hardware issue. I mean if you cloned to the other system and the problem goes away, it can't be any driver or anything you have.

Only other thing I can think of is to try running the built in Apple Hardware Test. Instructions here.

I'm afraid you are going to need to take this in to Apple or an Apple repair center for some troubleshooting.

Kernal_task chewing up 200% CPU at idle is definitely not normal.

[Steadiclarke]

I've been going through a bunch of these threads and no one seems to be really addressing the real issue... Or finding a solution for it is what I mean... This kernel_task is driving me crazy - yesterday I was working in Photoshop CS6 with Bridge CS6 open too and Google Chrome... kernel_task was steady at about 900-ish MB - I have 8Gigs of RAM - (sorry, no screenshot, you'll just have to take my word for it) - In Activity monitor my 350 MB multiple layer Photoshop File would eat about 4.2 Gigs of RAM and the system memory would drop my "Free Memory" (green) sometimes to 22MB when it was churning away.

I mean, with Snow Leopard I have run FCP7, Adobe Photoshop CS4, Illustrator CS4 and Word and Bridge all at the same time without even a hickup or slow down on a 4GB machine! really... Now I have this "amazing" machine and Google Chrome sometimes can't even load a page when I have the above (Adobe Ph CS6 and Bridge CS6 and Chrome) running at the same time....

I used to Love Mac and I switched to Mac from Windows because Windows would do exactly what kernel_task seems to be doing right now: HOG MEMORY IT "THINKS" it may need? Really?

Can I even go back to Snow Leopard? My Mac is a September 2012 MacBook Pro with 8 gigs of RAM (and yes, I'll upgrade to 16 GB this week!..) but what can be done do make this better? All I'm reading is:

"This is Normal"...

((((

[TattooedMac]

Originally Posted by Steadiclarke

Can I even go back to Snow Leopard? My Mac is a September 2012 MacBook Pro with 8 gigs of RAM (and yes, I'll upgrade to 16 GB this week!..) but what can be done do make this better? All I'm reading is:

Did you read the WHOLE thread ?? I think back in post #9 is what you are looking for.
Can you go back to SL, in short NO. You can not go back to a older OS than what the Machine Shipped with. It would of shipped with Lion 10.7 so you won't be able to put SL 10.6 on it what so ever.

As long as the %CPU is not high i really wouldn't worry about it to much. My Kernal_Task is running @1.37GB ATM with %CPU @1.2-3.8% and i have 8gb RAM on a Mid 2012 13"MBP. No problems with slow down here.

If your OCD use something like Oynx (Get the .V for your OS) or MainMenu MainMenu 1.7.4 Free Copy ~ DONT UPDATE and run all the tasks, except the Spotlight Reindexing and .DS_Stores then restart and see if that makes a difference. (It Should) then go back to enjoying the Mac OS X

Cheers

[Steadiclarke]

Originally Posted by TattooedMac

Did you read the WHOLE thread ?? I think back in post #9 is what you are looking for.
Can you go back to SL, in short NO. You can not go back to a older OS than what the Machine Shipped with.

TattoedMac... Thanks for the reply... but that was a rhetorical question