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GestureStew

macrumors newbie
Original poster
Sep 4, 2014
10
0
OK so I'm writing this on my brand new 2014 Macbook air 11" which now seems to be stable.

I was getting Kernel_task cpu usage ALL DAY yesterday of around 300%... The mac was virtually unusable. Fan was noisy, screen was jittery and the OS was unresponsive. I tried shutting it down, NVRAM reset and safe mode, none of it worked.

Last night I shut it down via the log in screen, went to sleep, and today it would not turn on (magsafe charger not connected).

Plugged in the charger for five minutes, pressed the power button and now all seems to be fine! Screen refresh rate is smooth, apps are responsive, and no crazy fan noise.

I am currently powering it off the fully charged battery and OSX is claiming I have 11hr 55 mins remaining with screen brightness at 2/3, no music play and only Safari running. All seems fine (is that battery estimation alarmingly high though?).

What worries me is that there might be some fault in the hardware that could rear its ugly head in the future... Is this likely?

Has this happened to any of you? Should I return it for a new one even though it seems to be working fine now?

Thanks for reading.
 
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Based on your description you did not have a kernel panic. So did you have one, or did you not have one?

My apologies, probably used the wrong phrase. The tech support guy I spoke to about the issues I was having called it Kernel panic. As aforementioned Kernel_task was causing severe CPU activity and making the mac unusable... Can I clarify some more or does that explain it?

Cheers
 
My apologies, probably used the wrong phrase. The tech support guy I spoke to about the issues I was having called it Kernel panic. As aforementioned Kernel_task was causing severe CPU activity and making the mac unusable... Can I clarify some more or does that explain it?

Cheers

When you first turn on a new Mac the OS build an index that Spotlight uses to search for files. While that is going on there will be a spike in CPU usage and the machine will be somewhat slower than normal. Depending on how much data you have copied over to the machine, that can take anywhere from 30 minutes to a few hours. It sounds to be like that may be what was going on here and by continually restarting and all you were interrupting that index process and it had to start over each time. Now that the initial indexing is over with this problem should go away.
 
Also, your 11 hour + battery estimation is not alarmingly high. It's normal and within spec, and one of the selling points for the MacBook Air.

My 13 inch MBA under load gets 7 hours, and when not being worked too hard, 13-14 hours isn't uncommon.

FYI, this is what a kernel panic looks like. If you didn't see one of these two images on your screen, then it likely wasn't a kernel panic:

TS3742_01_KP-001-en.jpg


TS3742-ML_Panic-001-en.png
 
When you first turn on a new Mac the OS build an index that Spotlight uses to search for files. While that is going on there will be a spike in CPU usage and the machine will be somewhat slower than normal. Depending on how much data you have copied over to the machine, that can take anywhere from 30 minutes to a few hours. It sounds to be like that may be what was going on here and by continually restarting and all you were interrupting that index process and it had to start over each time. Now that the initial indexing is over with this problem should go away.

I transferred absolutely nothing to the mac nor did I install any none-OSX programs, drivers etc.

It seems odd that it would need to index things when I haven't installed anything... I only changed input language and added my Google log in info when I first started it up, with minimal sync options.

Also, I did leave it on for about 20 minutes yesterday and it didn't quiet down. But I will try for half an hour.

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OK, now I'm back on a different computer, because the kernel_task is once again taking up all cpu function.

It seems to have been triggered after I've restarted OSX, after having just installed a driver for my audio interface that has not even been plugged in via USB yet.

I think this particular device has something very wrong with it. :( Whether it's hardware or software I don't know
 
I transferred absolutely nothing to the mac nor did I install any none-OSX programs, drivers etc.

It seems odd that it would need to index things when I haven't installed anything... I only changed input language and added my Google log in info when I first started it up, with minimal sync options.

Also, I did leave it on for about 20 minutes yesterday and it didn't quiet down. But I will try for half an hour.

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OK, now I'm back on a different computer, because the kernel_task is once again taking up all cpu function.

It seems to have been triggered after I've restarted OSX, after having just installed a driver for my audio interface that has not even been plugged in via USB yet.

I think this particular device has something very wrong with it. :( Whether it's hardware or software I don't know

Even if you put zero documents on there, a new mac still needs to build the Spotlight index. But a new MBA with no documents added should get that index process done in 20-30 minutes tops. You can click on the Spotlight icon and see if the index is underway.

If you installed a driver that is not compatible with Mavericks, it certainly can cause issues like this. Try a boot to safe mode and see if that stops the CPU spike. Safe mode stops any login to startup items from running and will bypass the audio driver. If the issue stops while in safe mode that tells you the audio driver (or something else you installed) is causing the issue.
 
Even if you put zero documents on there, a new mac still needs to build the Spotlight index. But a new MBA with no documents added should get that index process done in 20-30 minutes tops. You can click on the Spotlight icon and see if the index is underway.

If you installed a driver that is not compatible with Mavericks, it certainly can cause issues like this. Try a boot to safe mode and see if that stops the CPU spike. Safe mode stops any login to startup items from running and will bypass the audio driver. If the issue stops while in safe mode that tells you the audio driver (or something else you installed) is causing the issue.

Thanks for your suggestions, Weaselboy. As previously mentioned, this issue was occurring before installing anything at all.

When in spotlight I can see indexing finishes long before the problem continues.

The driver I installed ten minutes, or so, ago is made for Mavericks.

I also tried safe mode to avail yesterday.

Cheers
 
Thanks for your suggestions, Weaselboy. As previously mentioned, this issue was occurring before installing anything at all.

Yeah... I get that. But I was thinking the original issue was related to Spotlight indexing (and you rebooting in the middle of it), and that issue seems to have settled down and now a new driver install caused it to come back.

Safe mode would not stop the Spotlight indexing issue, but would diagnose a bad driver issue. I would try safe mode again now and see what you get.
 
If you're still having trouble, then I would would suggest using Internet Recovery Mode (boot up while holding down Command+Option+R) to fully wipe and reinstall the OS (of course, back up any documents or work you've put on there that you want to keep before doing this). Do a clean reinstall of the OS, then boot and let it do its spotlight thing for 30-45 minutes.

Then, use it and see if the problems continue. If they do, then it's time to set up an appointment at your local apple store to have them look at it for you.
 
I would simply exchange it for another one. Sounds like you have put in more than the reasonable amount of time trying to address this. I would think this is certainly not the "out of the box" experience Apple expects its customers to have.
 
Yeah... I get that. But I was thinking the original issue was related to Spotlight indexing (and you rebooting in the middle of it), and that issue seems to have settled down and now a new driver install caused it to come back.

Safe mode would not stop the Spotlight indexing issue, but would diagnose a bad driver issue. I would try safe mode again now and see what you get.

I tried safe mode again and it hasn't changed anything.

From what I've observed it seems like there a problem with power maybe?

The fact I couldn't start it this morning on a full charge seems very strange... then I plug it for five minutes and it's back up and running again. The only time it has behaved normally was this morning immediately after me not being able to turn it on. The problem arose again once I restarted it (after indexing was complete)

Thanks again.

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I would simply exchange it for another one. Sounds like you have put in more than the reasonable amount of time trying to address this. I would think this is certainly not the "out of the box" experience Apple expects its customers to have.

Agreed
 
I tried safe mode again and it hasn't changed anything.

From what I've observed it seems like there a problem with power maybe?

The fact I couldn't start it this morning on a full charge seems very strange... then I plug it for five minutes and it's back up and running again. The only time it has behaved normally was this morning immediately after me not being able to turn it on. The problem arose again once I restarted it (after indexing was complete)

Thanks again.

Sounds like that things is busted. I would exchange it pronto.
 
If you're still having trouble, then I would would suggest using Internet Recovery Mode (boot up while holding down Command+Option+R) to fully wipe and reinstall the OS (of course, back up any documents or work you've put on there that you want to keep before doing this). Do a clean reinstall of the OS, then boot and let it do its spotlight thing for 30-45 minutes.

Then, use it and see if the problems continue. If they do, then it's time to set up an appointment at your local apple store to have them look at it for you.

Thanks for your suggestions also, but the unstable nature of this brand new mac is screaming for a exchange or refund.

Thanks for your help clarifying, everyone. It's sincerely appreciated
 
Thanks for your suggestions also, but the unstable nature of this brand new mac is screaming for a exchange or refund
Not really. I've seen countless examples of cases similar to yours, where a simple system reinstall has fixed it. Sometimes things just go haywire, when tens of thousands of files has to be copied.
 
Not really. I've seen countless examples of cases similar to yours, where a simple system reinstall has fixed it. Sometimes things just go haywire, when tens of thousands of files has to be copied.

Countless examples of when a brand new mac doesn't work properly? That's worrying... The reason I got this is because I wanted something I can rely on for work on the road. Hmm, considering a Sony Vaio now....










































41Dk7zgI1KL._SL500_SS120_.jpg


But honestly thanks for the suggestions. I will consider reinstalling Mavericks before I return it. Still not hugely comfortable with the whole situation though.
 
Thanks for your suggestions also, but the unstable nature of this brand new mac is screaming for a exchange or refund.

Thanks for your help clarifying, everyone. It's sincerely appreciated

I'd get a new one.

People are fools for telling you how to fix a brand new computer. Its brand new - if it doesn't work 100% correctly out of the box it is considered DOA. You should not have to fix it - Apple should replace it.

It's one thing if its some crapware that was preinstalled (which thankfully Apple doesn't do), but its another thing if its the system itself messing up. Could be a bad component making the kernel freak out.

End of story.

Sounds like that things is busted. I would exchange it pronto.

This.



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On a related note. (correctly functioning) Spotlight indexing should have no noticeable effect on the speed of the machine for normal use. Whenever I have to reinstall I copy over hundreds of thousands of my documents, and whilst spotlight is doing its thing I can do other tasks, including installing photoshop or playing games, with nearly zero CPU slowdown. Spotlight at most will slow down drive access a bit, but CPU usage should not be a major issue.
 
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I'd get a new one.

People are fools for telling you how to fix a brand new computer. Its brand new - if it doesn't work 100% correctly out of the box it is considered DOA. You should not have to fix it - Apple should replace it.

End of story.

I completely agree apart from the 'fools' bit, I really do appreciate the 'fools' that are trying to help.

This is an inconvenience, that I assume is a rarity, that I wanted to see if there was a simple fix for... There's a 99% chance it's going to be returned due to no guarantees that the hardware isn't faulty.
 
Countless examples of when a brand new mac doesn't work properly? That's worrying...

No more worrying than when it happens on other platforms. I merely suggest doing the software reinstall because the moment you take it back to the Apple Store for help, that's the first thing they're going to ask if you did. And when you say no, they're going to do it themselves. And while there's by no means a guarantee, there is still a good chance it will work fine afterwards.

Doing the reinstall will save you that extra step, and may save you a trip back and some aggravation. But, if getting a whole new mac or a refund will make you feel better, then do whatever makes you feel comfortable.

The reason I got this is because I wanted something I can rely on for work on the road. Hmm, considering a Sony Vaio now....

Again, do whatever makes you feel comfortable.

And yeah I saw the trollface, and I'll still say: if getting a Vaio makes you feel better, don't joke about it and just do it. That's a far better thing to do than the people we see on here exchanging 5, 10, 15 or more Apple devices because they see imperfections in each and every one (real or imagined? We'll never know), and are hell bent on getting one that's absolutely "perfect."
 
OK, just a quick follow up in case anyone might care.

I bought this Mac from Amazon, the seller offered a refund but no replacement.

Saw that all the prices across Amazon had gone up since purchasing, decided not to take the refund option.

Took it to the Mac Store; they ran some tests and it turns out the CPU was faulty.

They're replacing the entire board so hopefully it'll be back with me this week.

Thanks again, everyone.
 
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