Q: kernel_task is using 100% CPU when waking from sleep

Fix coming? http://www.macrumors.com/2014/02/18/sleep-wake-crash-macbook-air/

am I the only one who considered getting an Apple Dev account ($100/year?) to get the possible fix in the 10.9.2 beta?

I tried to force stop/continue various processes at sleep and wakeup, and many combinations of them, using "sleepwatcher". I'm sure there are more processes and more permutations but I'm tired and fed up. I think I'm barking at the wrong tree by stopping/continuing processes.

My daily routine begins with a OS X update check lol

FYI, I was seeing this due to using Boom (http://www.globaldelight.com/boom/) which like someone said here forces a non-apple audio driver.

As soon as I quit it, kernal_task dropped from > 100% to around 2% and battery estimate returned to normal.

I'm sorry but this doesn't solve the problem since most of us aren't using Boom.

Thanks anyway for your feedback.

I didn't post it as a solution, just as supporting information that might help someone else like me who stumbles across this thread.

Hi

I've observed the same issue with kernel_task running hot, with it's CPU utilisation up in the > 80% arena, sometimes getting close to 100%.

I've not been actively monitoring with Activity Monitor, but did look when my 2012 MacBook Pro with Retina Display seemed to slow down from time to time.

I'm not using a wired headphone cable or Boom, but the suggestions did make me wonder whether iTunes was part of the problem - audio subsystem seemed to be the consensus.

I'm running iTunes 11.1.4 on Mac OS X 10.9.1 Mavericks.

I have seen a few crash reports from iTunes, normally when I wake up the Mac from sleep.

Therefore, putting two and two together, I terminated iTunes, and immediately saw the CPU utilisation for kernel_task drop down to single figures - as I write, it's sitting at 2.8%.

Therefore, audio does seem to be close to root cause.

Next time I get a crash report, I'll send it in, as per usual, but also link this forum thread to my report.

Cheers, Dave

Sorry, wrong thread.

Hi just FYI, for me the solutions was to disable third party kernel plugins (i was struggling with this two days instead of work…).

I had four plugins installed, I found them via this command:

kextstat -kl | awk '!/com\.apple/{printf "%s %s\n", $6, $7}' | open -ef

(plugins are located in: /System/Library/Extensions/)

I disabled only the soundflower extension because after googling all the plugins i found this information on soundflower:

According to OS X 10.8's GateKeeper application, Soundflower's app certificate has been revoked. GateKeeper recommends that you refrain from installing Soundflower 1.6.5.

I was going to disable all four but it seems the first one was the problem…

Hi,

Ok, my issue is on a MBP 8.2 runnging ML but having the same result (kernel task taing all CPUs).

I found that really nice post http://www.rdoxenham.com/?p=259

ANd boy, looks like it finally solve the problem I was having for months.

Maybe it can be helpfull

L.

The particular issue mentioned on this thread looks to be specific to an audio related issue, when waking from sleep, on 2013 computers, with OS X Mavericks, leaving kernel_task between ~99-110% of CPU. The issue mentioned on that link occurs on older operating systems, and is related to throttling when there is a issue with the temperature sensors or cooling system.

kernel_task controls many things, and there are a number of ways its CPU usage can go out of control, but it looks like that post is referring to a different issue from the one this thread focuses on.

Seriously Apple!?!?!?! Fix this **** problem NOOOOOW.

I am tired of having my MBPr behaving like this!!!!!!!

Good news everyone, the problem is fixed in OS X 10.9.2. I can put my MBA to sleep with earphones and Safari opened with flash content and the kernel_task bug no longer occurs. The update also fixes the occasional crash that can happen if you put your MBA to sleep and press a key or the trackpad at the same time.

I am also having the issue where kernel_task is using 100% of the first CPU core when the cover is closed and in sleep mode. In fact today it happened again overnight and my battery was at 0% when I opened the Macbook Air. Only started happening after updating from 10.8.6 to 10.9.1.

I have now updated to 10.9.2 and hopefully it will fix this issue.

yes it's fixed now with 10.9.2! I'm confirming this issue is fixed on late 2013 rMBP. I've tested with xbmc and Flash playing in Safari.

it feels as if my macbook is finally out of intensive care unit, unhook all those monitoring devices and finally healthy!

I can confirm that the kernel issue is finally gone.

Nice.