Kernel Task and RAM

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Level 1

110 points

Kernel Task and RAM

Hello again, Apple Friends.

Recently I have noticed that kernel_task in Activity Monitor is running at anywhere between 60MB and 200MB of RAM, which is really slowing things down. I have searched on the discussion boards the past few days and have found similar posts related to MB Air and old Powerbooks, but nothing about iBooks.

The kernel_task process will run, using up lots of RAM, even if I have no apps running whatsoever. If I let the iBook idle, over the course of 15 minutes (nothing running) it goes from 60MB to 150MB, with anywhere from 47 to 60 threads. That's when idling!

What I've tried to eliminate: (none of the following are the problem)

Firefox 3
any and all items / drivers in my login startup (the only ones I have not tried removing are those that are Apple)
resetting PRAM (did this)
Repaired disk permissions (did this 2 or 3 times, and each time after checking other items above).

I do not regularly have any peripherals attached, and the problem has existed without peripheral devices. I did get new RAM added a few months ago (I went from 516MB - or something like that - to 1.25GB) and I am wondering if this is part of the problem? But I have only noticed the problem recently. I'm not receiving any kernel panics, and so I'm not too worried, but I am really wondering if there is something amiss I should be worried about. And when I start using other major-memory apps (like iTunes, for example), the kernel_task process goes wayyyyy up (to 250MB or more).

I should add that I have also tried all suggestions listed in this thread, but to no avail.

Does anyone have any ideas?

iBook G4 1.2GHz (PowerPC), Mac OS X (10.4.11)

Posted on Oct 26, 2008 3:40 AM

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Answer 1

Oct 26, 2008 8:33 AM in response to adrienne_am

What you are describing is completely normal. I see no reason to think it is a problem. If you are having a problem, I see no reason to think it is related to kernel_task.

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Answer 2

adrienne_am Author

Level 1

110 points

Oct 26, 2008 9:05 AM in response to Jeffrey Jones2

Hmm. Well I generally define it as a problem if it is A)new, B)unusual, or C)affecting performance. In this case it is all of the above. I regularly monitor my CPU % and RAM usage and I think it's strange that it would suddenly spike, and then stay this way. Plus, like I said, it affects system performance in that it seems to make regular applications sluggish.

I can't think of another reason my system would be sluggish other than RAM or CPU usage. And kernel_task is often at the top of the list in Activity Monitor when sorted by memory. Currently the kernel_task is using 63MB Real Memory and 969MB of Virtual Memory, and I have only had my iBook up and running for 5 minutes.

Don't get me wrong - I am open to other ideas. But I have (I thought) eliminated most of what those could be, simply by trial and error. What else do you think could be the issue?

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Answer 3

BDAqua

Level 10

250,259 points

Oct 26, 2008 1:31 PM in response to adrienne_am

If the kernal_task is growing without any APPs running, I'd check the Console Logs for some process failing and retrying ever few seconds/minutes.

Mine is @ 144MB/1.22GB right now.

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Answer 4

adrienne_am Author

Level 1

110 points

Oct 26, 2008 11:10 PM in response to BDAqua

BDAqua wrote:
... check the Console Logs for some process failing and retrying ever few seconds/minutes.

Hi BD,
Thanks for this tip. I have checked the Console logs and there was some process failing about 3 weeks ago, but I am quite inexperienced at reading these logs and so I'm not sure what to make of it. What should I look for?

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Answer 5

BDAqua

Level 10

250,259 points

Oct 27, 2008 12:05 AM in response to adrienne_am

The key is to try to let it sit doing nothing after login, if it increases still little by little, then we'll have to look deeper, but kernal task handles all background stuff.

BTW, another Mac right now is at 239.29MB/1.71GB.

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Answer 6

adrienne_am Author

Level 1

110 points

Oct 27, 2008 5:41 PM in response to BDAqua

Well, I have discovered something interesting. After your advice, BD, I tried a few things. First of all, after login, just leaving the computer idling, the kernel task does increase gradually over the course of 15 minutes -- I have tested this 3 times and it usually starts at around 60MB from login and creeps up to anywhere from 75MB to 120MB at the end of 15 minutes.

But then I wondered if it was somehow connected to my login account. I realized this problem only occurs under my main account. This account is not an admin account (I have a separate one for that). I logged in with 3 different accounts (boyfriend, Visitor, and my brother's) and none of them even had the kernel task running on login. Yet under my main account, it is running, starting at 60MB and with 47 threads.

Is this unusual? My next trick is to leave it idling for 30 minutes after login to see how much the memory use increases. But I am really curious now.

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Answer 7

Oct 27, 2008 6:57 PM in response to adrienne_am

In the other accounts, you are probably looking at "My Processes" rather than "All Processes". kernel_task is fundamental to the operation of Mac OS X. It is not possible to function without it.

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Answer 8

BDAqua

Level 10

250,259 points

Oct 27, 2008 7:36 PM in response to adrienne_am

Is Spotlight running perhaps?

Can you let it sit overnight from a fresh start?

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Answer 9

adrienne_am Author

Level 1

110 points

Nov 4, 2008 3:55 AM in response to BDAqua

Apologies for the delay in reply. I have been without internet access in Hanoi due to the severe flooding.

I have tried it from a fresh start 3 times, let it sit overnight, and all 3 times it seemed to "bottom out" at around 83MB, which is good news. I am thinking perhaps that all it needed was a few restarts in a row. Have repaired permissions, too, just to be safe.

Thanks for the help; I think this question is answered.

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Answer 10

Nov 4, 2008 6:22 AM in response to adrienne_am

Hi everybody!

I follow your discussion, but I didn't get the real solution to this problem.

Right now, Kernel_task uses 59,91Mo/819,47Mo. The computer accept to work normally but during the day it slows down a lot.

Is there any test I can run to detect witch application is asking so much virtual mem?
If it is normal that Kernel_task is the application using more VM than the otehrs, then the proble is somewhere else... Have you heard about viruses affecting Mac OS X ?

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Answer 11

adrienne_am Author

Level 1

110 points

Nov 4, 2008 7:30 AM in response to OlivierMTL

Hello, Olivier. The problem was never "solved", per se, but it did go away after I tried BD's suggestion of re-starting and letting it sit overnight. I did this 3 times and things seemed to be better, so I don't really have a problem any more.

I have noticed certain applications taking up more memory than others. In particular, the combination of Firefox 3.0 + iTunes 8.0 is a terrible one -- eats up nearly 1GB of my 1.25, meaning my entire computer gets very very slow. So now I've gotten into the habit of using Safari when playing iTunes... not my first choice, but I am taking this as a sign that I need to upgrade my iBook -- it is, after all, 4 and a half years old. That 1.2GHz processor is working very hard!

Not sure if this will help you... you can try what I have tried, or post a separate message with your specific symptoms -- perhaps it is a different problem than mine? Good luck!

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