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CPU Spikes?

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vtyler98

macrumors member
Original poster
Jul 27, 2011
66
9
Occasionally I will be using my 2011 13" Air and the CPU will spike to 40-50% usage and then quickly go right back down. The only applications I have open is Google Chrome (flash blocked, turned off) and my activity monitor. It isn't too bad but it gets annoying because I'll just be browsing the web and all of a sudden I feel the computer heat up and so checking the computer temp the CPU will jump to 65-80C range and the fans kick on to 4000+RPM and then in about 30 seconds it calms back down. I have had my laptop for around 2 weeks now so I don't think it would be spotlight indexing by now. Here is a screenshot showing the running processes and the spike, I can't seem to catch a screenshot of the actual process running when it spikes so I'm not sure what it may be? Any suggestions? Also, below is a screen shot showing the CPU around only 1% yet the temp is rising rapidly to above 60C (peaked at 85C a few seconds after this then cooled back down) while the fans are around 5400rpms.
 

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calvol

macrumors 6502a
Feb 3, 2011
995
4
The heat is caused by TurboBoost kicking in, which has a max freq of 2.9Ghz. When the CPU has a single-threaded process queue, TB ramps up until the temp of the CPU reaches a defined limit. You can probably find out which process is causing this by looking at your Activity Monitor during the heat spike, unless it's the IGP causing TB to kick in, which I don't think is diplayed in AM. I have a Sandy Bridge i5-540M on another PC laptop, and it does the same thing, especially when I open a bunch of browser windows. SB has a rather "peaky" heat profile due to the TB.

http://www.anandtech.com/Show/Index/...ecture-exposed
 
Hellhammer

Hellhammer

Moderator emeritus
Dec 10, 2008
22,164
582
Finland
You have to select ALL PROCESSES and sort the processes by CPU usage in Activity Monitor to get an accurate idea of what is going on. Now it ignores all system tasks.
 
V

vtyler98

macrumors member
Original poster
Jul 27, 2011
66
9
Hellhammer said:
You have to select ALL PROCESSES and sort the processes by CPU usage in Activity Monitor to get an accurate idea of what is going on. Now it ignores all system tasks.
Click to expand...

Took a screen shot and it shows kernel task as the most consuming application running, but it isn't one which I can quit so I assume it has something to do with the computer system? I'm new to mac since I was a former PC user, had a Toshiba Satellite but recently bought the new 13" air and I really like it so far. Thanks for the suggestions so far everyone! Here is a screenshot below of all the processes running sorted by amount of threads.

Calvol, thanks for the info! The link does not work however, can you try it again? It definitely seems like the spike you mentioned but I wonder if a process is causing it to turboboost like that, since all I typically use is safari, the app store, and word documents primarily.
 

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Hellhammer

Hellhammer

Moderator emeritus
Dec 10, 2008
22,164
582
Finland
vtyler98 said:
Took a screen shot and it shows kernel task as the most consuming application running, but it isn't one which I can quit so I assume it has something to do with the computer system? I'm new to mac since I was a former PC user, had a Toshiba Satellite but recently bought the new 13" air and I really like it so far. Thanks for the suggestions so far everyone! Here is a screenshot below of all the processes running sorted by amount of threads.
Click to expand...

The number of threads isn't that relevant, you have to sort the processes by CPU usage (the column on the left from threads). As you can see, WindowServer process is taking over 20% of one of your threads (the maximum usage is 400% since you have four threads). That process is a system process and cannot be quit. I think it handles all windows and other UI graphics, which can be quite demanding sometimes. I have noticed that this specific process takes more CPU in Lion compared to SL (possibly due to Lion's heavier animations).
 
V

vtyler98

macrumors member
Original poster
Jul 27, 2011
66
9
Hellhammer said:
The number of threads isn't that relevant, you have to sort the processes by CPU usage (the column on the left from threads). As you can see, WindowServer process is taking over 20% of one of your threads (the maximum usage is 400% since you have four threads). That process is a system process and cannot be quit. I think it handles all windows and other UI graphics, which can be quite demanding sometimes. I have noticed that this specific process takes more CPU in Lion compared to SL (possibly due to Lion's heavier animations).
Click to expand...

Ok thanks, I sorted by CPU and it appears WDsmartware (my external HD) is causing it to ramp up to 85% and higher (hit 200% briefly). I tried to quit the process but it didn't quit, even after hitting force quit it seems to keep coming back. I disconnected my external HD and then tried to quit it but still not luck, so then uninstalled WDsmartware from my applications folder and tried to quit it but it is still running? Other applications running are easy to force quit but this one seems to be persistent.
 
C

calvol

macrumors 6502a
Feb 3, 2011
995
4
vtyler98 said:
Calvol, thanks for the info! The link does not work however, can you try it again? It definitely seems like the spike you mentioned but I wonder if a process is causing it to turboboost like that, since all I typically use is safari, the app store, and word documents primarily.
Click to expand...

Ok, the link is to Anand's website, but it appears to be down at the moment. I'll check it again later... interesting that the Windows Server process utilizes so much of the cpu
 
Hellhammer

Hellhammer

Moderator emeritus
Dec 10, 2008
22,164
582
Finland
vtyler98 said:
Ok thanks, I sorted by CPU and it appears WDsmartware (my external HD) is causing it to ramp up to 85% and higher (hit 200% briefly). I tried to quit the process but it didn't quit, even after hitting force quit it seems to keep coming back. I disconnected my external HD and then tried to quit it but still not luck, so then uninstalled WDsmartware from my applications folder and tried to quit it but it is still running? Other applications running are easy to force quit but this one seems to be persistent.
Click to expand...

http://hintsforums.macworld.com/showthread.php?t=111627

That thread might be helpful in that case. Apparently, it is a real troublemaker and making it disappear doesn't seem too easy either.
 
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