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tgd85

macrumors member
Original poster
Sep 18, 2013
41
6
Currently my CPU is running 13% when completely idol. System % is constantly in the range of 12-14%. But I can't find the leak. Nothing in Activity Monitor shows high system CPU usage. How can I find out what's causing the leak?

Edit: kernal_task is showing 65% CPU usage. What's going on here?
 

tgd85

macrumors member
Original poster
Sep 18, 2013
41
6
Thanks for the advice. After a few shutdown / restart cycles, it seems to be operating again at normal levels.

Just out of curiosity, why would installing a recent upgrade cause that to happen? I installed the upgrade a few days ago and hadn't noticed anything until my machine literally became hot to the touch.
 

tgd85

macrumors member
Original poster
Sep 18, 2013
41
6
I'm still experiencing this issue. High system CPU usage starts immediately after booting from shutdown. Always between 12- 15% kernal_task. The issue persists over several shutdown / restarts. After a few cycles, it disappears for that particular boot, but then reappears upon rebooting.

Any ideas?
 

h9826790

macrumors P6
Apr 3, 2014
16,656
8,587
Hong Kong
I will say 12- 15% kernal_task is normal. Not really high CPU usage. Some system background activity (e.g. indexing, Time machine, etc) may cause this kind of CPU usage (or higher).

Just 12-15% of a core, really nothing to worry about. You better let the OS handle itself rather than disturb it.
 
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tgd85

macrumors member
Original poster
Sep 18, 2013
41
6
My fault for not explaining more. These are the readouts from Activity Monitor.

kernal_task CPU = 66.5% CPU Time = 8:04 Threads = 107 Idle Wakeups = 55,135

The 13% I was referring to was the total System %. (quad core machine)

After about 15 reboots, it's finally back down to 2.4% or 0.5% of total System. I'm terrified to reboot my machine again...
 

ScoobyMcDoo

macrumors 65816
Nov 26, 2007
1,188
37
Austin, TX
You should be able to patch it right up with some JBWeld.

Seriously, you are chasing a non-issue. If it is showing high CPU utilization, that means it has something it needs to get done.
 

tampageek

macrumors 6502
Jul 1, 2015
343
537
Florida, USA
I have been going nuts with this issue since upgrading to 10.10.4. Today I finally bit the bullet and did a clean install with a bootable USB I made. Problem solved - and my battery draining issues also solved. I had no idea how smooth Yosemite could be.

Clean install solves all- at least for me it did.
 

tgd85

macrumors member
Original poster
Sep 18, 2013
41
6
I have been going nuts with this issue since upgrading to 10.10.4. Today I finally bit the bullet and did a clean install with a bootable USB I made. Problem solved - and my battery draining issues also solved. I had no idea how smooth Yosemite could be.

Clean install solves all- at least for me it did.

I'm hoping to avoid that fate if possible, but it's good to know that did the trick. There are a few posts from others who are experiencing a similar issue over at the Apple Support forums.

I wasn't having any issues prior to the recent update. Were you able to restore from a backup after the clean install?
 

tampageek

macrumors 6502
Jul 1, 2015
343
537
Florida, USA
I'm hoping to avoid that fate if possible, but it's good to know that did the trick. There are a few posts from others who are experiencing a similar issue over at the Apple Support forums.

I wasn't having any issues prior to the recent update. Were you able to restore from a backup after the clean install?
Actually...no. All my backup drives (3 separate ones) would only allow me to access "today" even though it showed there were dozens there. I think this may have to do with the firmware update and Apple's gradual push (as in OS X 10.11 SIP) to block everyone (but them) from access to the hard drive. This also hinders the users the ability to roll back the OS to a stable version.

Fortunately I keep copies of photos and important files on thumb drives so I was able to restore them individually. Pain the butt but it worked.

So Upgrader's beware - and make ordinary copies of your files because the time machine backup to the previous OS may NOT work!
 
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