kernel_task is using 100% CPU when waking from sleep

Hi, I'm also reporting that my late 2013 MBP 13" with Mavericks and this kernel_task stuck at 100% issue when:

- Only if a Flash or HTML5 video has been running and computer is put to sleep. Regardless of the type of browsers used. My source of Flash video and HTML5 video is Youtube

- then computer is waken up

- regardless of a headphones are plugged in or not.

- this happens EVERY TIME.

What works to put the kernel_task back to low teens:

- log out and back in. A full reboot also works but not necessary.

- *sometimes works* if i was on headphones, unplug the headphones, put my MBP to sleep and wake it up.

- "what i believe works" play something in iTunes and while it's playing put my MBP into sleep and wake it up.

What doesn't work for MBP as opposed to what's reported to work here for MBA:

- using AppleHDA kext from 10.8.5.

- unloading AppleHDA kext and reloading it. The sound is lost and requires a reboot to get it back.

- Putting MBP to sleep and waking up without headphones or iTunes tricks above.

What it does to my daily usage pattern:

- I have been checking on the Activity Monitor for kernel_task annoyingly, obsessively and compulsively.

how do you do this ktext thing? I keep getting:

"The system extension “/System/Library/Extensions/AppleHDA.10.8.5.kext” was installed improperly and cannot be used. Please try reinstalling it, or contact the product’s vendor for an update."

when I drag and drop, and Terminal keeps giving me error messages.

donkim0822

I have late 2013 MBP 13" with Mavericks.

i can't repeat that:

"Only if a Flash or HTML5 video has been running and computer is put to sleep."

BUT somehow I can't anymore repeat ANY earlier methods to put kernel_task to 100%. I reported many methods to this thread 01/11/2014 how my MBP kernel_task goes to 100% but somehow I can't even repeat those methods.

It has been about 4 or 5 days when my MBP hasn't gone "100%". and I haven't done any "fixes" or reinstallations or whatever. And I also have been checking on Activity Monitor for kernel_Task annoyingly and compulsively but nothing has happened. Very strange.

Could it be some kind of indexing task and it's completed?

I even have more cpu time in Google Chrome than kernel_task with 1 day uptime. Before, when my kernel_task used 100%, I had about 2 or 3 times cpu time assigned to kernel_task / day vs Google Chrome.

I get those messages too. I think I ruined the kextfile when I tried to put back the original one. When I repair disc permissions, I get alot of messages that the HDA kext-file is corrupt more or less.

I used John_Raz's method in previous page. Thanks John. You need to with sudo in terminal for each and every command.

I was worried I'd mess up so I took a Time Machine backup, made sure the kext was backed up, then created a tarball of AppleHDA.kext folder and then moved it to AppleHDA.kext.disabled folder before I copied 10.8.5 kext in place. Since I'm new to MacOS and doing something I never did, I wanted a somewhat reliable way to go back just in case. 🙂

Anyhow, this method ain't working for MBP so I'm praying for a new update from Apple.

Reinstalled OS X early this morning, and the problem has not shown yet. Maybe too early to say the problem is gone, but under the same circumstances as before, the kernel process is behaving properly.

Maybe I jinxed it now.... 😠

Thank you northwest! I "dirty" reinstalled Mavericks (i didn't erase anything on my disk) and the kernel_task cpu usage is now finally staying low where it belongs!

I tried putting my MBP to sleep and waking it up while playing HTML5 in Safari, and playing Flash videos in Chrome and Firefox and they all behaved!

btw, I find Safari's HTML5 extension from http://www.verticalforest.com/youtube5-extension/ more energy efficient than when it's natively playing Youtube in regular Adobe Flash.

Now I can play some music in the background and leave Activity Monitor alone.

I spoke too soon. kernel_task is back at 100%. ugh. I went to a Apple store and tried to make one of the 13" late 2013 MBP behave like mine.

and it didn't work. kernel_task is very low no matter what flash video I play and make it sleep and wake it.

ugh.

what to do what to do.

My Mac just came back from the Apple Store with a new Mainboard but it still doesn't fix the problem. I've replaced the AppleHDA-Driver (as seen here: https://discussions.apple.com/thread/5497235?answerId=23659683022#23659683022 ) since then I haven't had problems with kernel_task. Looks like this helped. Thanks to all of you.

Yup, my kernel task is back with full force. Not behaving at all. When I wake my MBPr from sleep, and the headphones are not plugged in, a solution is to start iTunes and start a song, then closing iTunes again.

I am not happy at all with this, and I think Apple should come forward with some kind of feedback since so many users exoeriences this problem. I have to run Activity monitor at all times so I can keep an eye on the kernel process.

The "dirty" reinstall of Mavericks did not do the trick. Disappointed long time Mac user...

It is easier to use the archive i have made which contain all the tools, readme and driver to replace and backup original AppleHDA.kext easily: http://puu.sh/5RBvj.dmg

Just wondering if it could be linked to that:

This bug is barely occuring for me at home.

But when I'm at my grandparents' house, their power outlet is old and only has 2 output (hence no earth connection). There, the bug happens all the time.

At home, I have 3 outputs on my outlet (with the earth connected) and it barely happens.

Do you think it could be linked?

it must work for MBA. For MBPr late 13 it doesn't. Thanks. I would like see if AppleHDA kext from MBP 15" works though. Maybe I should visit Apple store again to get a tarball or something.

For now, I just disabled sleep when the lid is closed with "No Sleep" app. It seems to use 1% of battery per hour for the 2 hours I had it closed.

ugh.

When I'm sure nothing's streaming/playing, I can hit the power button to put it to real sleep.

I found if anything is playing, online or local content in MPlayerX, Tuba, and Minitube and if computer is put to sleep, I'm guaranteed to get kernel_task at 100% when it's waken up.

Seems to be related with AppleHDA Audio Codecs (old ones from OS10.8 work), that's why when you guys unplug the headphones the CPU level cames to normal levels. This problem is still not solved.

I've been chating with some Apple amployees about it and they say it's a Maverick's problem. I've said them that so many people is having this problem in Apple's official forums and they reccommend me to say you guys to open a "Feedback Bug Report" in Apple's website: http://www.apple.com/feedback/

They told me that in the forums where you guys explain this issue, they don't read it them all, and the worst of all, apple enginyeers don't read them. So, i reccommend you to open a Bug Report in order to let them know about this problem and giving them enough information to solve it.

Thanks