kernel_task is using 100% CPU when waking from sleep

....you are right! i had this only on MacBook Air´s and -Pro´s, sorry!

But there it works.

All kind of workarounds are a shame for apple. If i see this long thread an other postings it looks like this is a big problem for a significant % of users. Why apple did not recognize this in the Beta test and now no change with 10.9.1....

Couldn't agree more. Apple clearly are nothing like the company they once were. I think we are long overdue a new "Apple" in the market place. I personally hope one comes along

does this have to do anything with the audio chip? It seems to happen on 2013 models more often. They also have a new audio chip: Cirrus 4208 CRZ while the older models have a Cirrus 4207

I found a temporary Solution for the kernel_task Problem.

(If you dont want to plug the power cable on and off.)

I bought a mini fan for about 10 € put it next to my macbook pro and turned it to the direction where the battery is. Wait a minute and watch in your activity monitor how the kernel_task slows down from 200% to 4,3 or something like that.. The only thing whats annoying is the sound wich comes from the fan. But thats a small price to pay :-)

I think another solution would be to completely delete your hardrive and install Snow Leopard.

But im to lazy to try that out so i just stick with my fan solution.

I have this setup for a year now and never had any kernel_task overheating (or whatever you call it) problems again. (even in games with much cpu usage)

I had that exact same suspicion, both the 2013 rMBP and MBA use that chip and they are the computers with this issue.

if that solves you problem, then you have a hardware issue. Your MacBook could be old and there could be dust in your Mac. High CPU usage of kernel_task is a sign of overheating.

Type this into terminal: sudo killall coreaudiod

I had issues streaming music to my appletv before (pre-itunes radio) and came across this command for "resetting" the audio stuff that runs in the background. It also works at getting rid of the 100% kernel for me.

"sudo killall coreaudiod" is a really bad idea - it will crash running applications. It also doesn't solve the problem.

Apple, please tell us, when are you going to fix this ridiculous bug?

It worked for me and I just had to hit play on itunes radio to get it back up and running. Nothing crashed for me, but the only application playing audio at the time was itunes so YMMV. Also it is another option for those that don't want to restart. I tried unplugging my headphones and putting to sleep, but it did not work for me.

Edit:

Also at the time I was running the below applications and nothing crashed.

Finder

Endnote

iCal

Notes

iMessage

Mail

iTunes

Safari

Mathematica

Matlab

Excel

Powerpoint

Activity Monitor

Adobe Acrobat

Thanks for the Tip. Opened my MacBook Pro, found a lot of dust, got rid of it and now it all works fine (without the mini fan).

really seems to be something with sound: I had the apple earpods plugged in, when I noticed the kernel_task eating 100% for a long time... when I read the thread I pulled them out - viola! gone! plugged them back in, but the process did not come up again. so, it's maybe two or more things that have to come together...? still: an anoying bug...

(13" MBPr late 2013, 2.6Ghz i5)

i just came across this after coming out of sleep, like everyone else here. it wasn't the first time, but it was the first time i bothered to search for others in my bood. i have a similar powermetrics.txt snippet:

---

**** Session Interrupt distribution ****

CPU 0:

Vector 0x20(): 0.00 interrupts/sec

Vector 0x46(SMC): 0.25 interrupts/sec

Vector 0x49(MacBookAir6,2): 20.42 interrupts/sec

Vector 0x92(IGPU): 322.54 interrupts/sec

Vector 0x94(XHC1): 114.36 interrupts/sec

Vector 0x95(pci8086,9c3a): 0.03 interrupts/sec

Vector 0x96(HDEF): 29171.14 interrupts/sec

Vector 0x97(ARPT): 77.10 interrupts/sec

Vector 0x98(CMRA): 0.00 interrupts/sec

Vector 0x9d(NHI0): 0.85 interrupts/sec

Vector 0x9e(SSD0): 46.15 interrupts/sec

Vector 0xdd(TMR): 876.63 interrupts/sec

Vector 0xde(IPI): 250.64 interrupts/sec

---

before i got a chance to play around further, i switched to another user i had logged in that was running VLC and quit VLC. still saw the kernel_task suckage. switched back to my regular user and the problem went away.

if the theory that this is related to a buggy AppleHDA.kext is true (which i think likely), will somebody try this possible workaround next time they see the issue and report back? i'm too lazy to try to see if i can repro the issue easily ;P

--

$ sudo kextunload /System/Library/Extensions/AppleHDA.kext

$ sudo kextload /System/Library/Extensions/AppleHDA.kext

--

thanks!

marc

I have a similar problem and thought I would mention it here although this is related to MacBook Air and I am using a MacBook Pro.

Anyway, Kernel_task is using upto 10 GB of my 16 GM Ram when I am trying to save a file from iMovie and then I get the message that the system has run out of application memory. Never had this problem in the older versions of OS and iMovie.

I use Apple TV and Apple Express to stream music, so it may be connected to the sound issue mentioned in the thread.

Any suggestions would be greatly appreciated.

By the way Genius Bar at the local Apple store is telling me I have a hardware issue. But all this started after upgrading to the latest OS etc.

Thanks.

Marc, you're a genius - this actually fixed it!

$ sudo kextunload /System/Library/Extensions/AppleHDA.kext

$ sudo kextload /System/Library/Extensions/AppleHDA.kext

CPU went back down to normal levels immediately after that. I would encourage everyone to try this one out.

Neither unloading and reloading /System/Library/Extensions/AppleHDA.kext nor the iTunes workaround do anything for me on my 2013 MacBook Air running 10.8.5. As I'm travelling I won't have the option to send my Mac in for repair for a while either... Very disappointed to search for the kernel_task issue and find a lot of workarounds like this one that don't work: http://www.rdoxenham.com/?p=259

Searching google, it seems this has been an issue on various hardware for multiple years. Makes me question buying hardware from Apple again seeing how silent they are on this issue.