iMac CPU usage high not from flash video

Discussion in 'iMac' started by JAWWC, Oct 30, 2009.

  1. JAWWC macrumors regular

    Joined:
    Jun 1, 2008
    #1
    I just want to make sure this is still the same problem everyone else is having with the CPU. Without safari open my system CPU usage spikes to 50% and stays there till I reboot after about 20 mins use.
    Sorry to make a thread about it but everyone else seems to be complaining about flash video and mine isn't.

    Cheers
     
  2. DrNelly macrumors member

    Joined:
    Jun 13, 2008
    Location:
    NJ
    #2
    I replied about this problem on another thread, but yeah, I am also having this problem. CPU seems to spike up to 80's with relatively simple apps like Dreamweaver or Adobe Bridge. Also watching locally stored 1080p videos is a choppy and very random experience... Then I reboot, everything is fine for another while and boom here we go again, slugfest with my brand new iMac :(

    I hope that together we can find a solution.
     
  3. spinnerlys Guest

    spinnerlys

    Joined:
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    forlod bygningen
    #3
    Have you both looked at Activity Monitor (Show All Process and sort by CPU) and seen what process might hog up the CPU?

    Have you repaired permissions?



    What Mac do you have and what Mac OS X do you run?


    Also MRoogle might give you already exisiting topics about this issue.
     
  4. DrNelly macrumors member

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    Jun 13, 2008
    Location:
    NJ
    #4
    I should update my signature..

    I use a brand new base iMac 27, yes I have repaired permissions, I have reset PRAM and I have reinstalled the latest version of flash player.

    Obviously I'm running SL 10.6.1 with very few apps installed and not using time machine backup or anything like that.

    Simply and plainly annoying issue to have on a 1700$ machine.
     
  5. spinnerlys Guest

    spinnerlys

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    #5
    What software is giving you this high CPU usage? Adobe Dreamweaver and Bridge? Are they compatible with Snow Leopard?
     
  6. DrNelly macrumors member

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    Jun 13, 2008
    Location:
    NJ
    #6
    I'm using Creative Suite 4 from Adobe with all the productivity applications. Unfortunately these are not the only pieces of software giving the CPU a tough time...

    I discovered that only one core gets really high while the other remains normal. It seems as if it was throttling one of the cores up and leave the other core alone. It might be SL internal resource system putting processes on one core and the user stuff on the other, but I don't know how SL does that.

    Also flash plug-in remains using between 20-30% of one core even when the safari window that contained it is closed. I kept other Safari windows open with no flash content whatsoever.

    I wish this was only a Safari problem.
     
  7. fr4c macrumors 65816

    fr4c

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    #7
    This is the same for me. One CPU core will get pegged and spike between 50%-80% even when the machine is idle. I will report later what system processes they are.
     
  8. iLog.Genius macrumors 601

    iLog.Genius

    Joined:
    Feb 24, 2009
    Location:
    Toronto, Ontario
    #8
    CS4 isn't the problem under Snow Leopard. Using Photoshop, Illustrator and Dreamweaver and there seems to be no problems in terms of increased CPU usage.
     
  9. DrNelly macrumors member

    Joined:
    Jun 13, 2008
    Location:
    NJ
    #9
    I know that, I use my SL MBP connected to the 23 cinema display 12 hours a day. :)

    The problem is when I try to do the same thing with my sparkling new 27 iMac

    ;)
     
  10. ryanfacer macrumors newbie

    Joined:
    Oct 26, 2009
    #10
    I am having these same problems:( One core doing all the work after the unit has been on for a few hours.
     
  11. DoFoT9 macrumors P6

    DoFoT9

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    Jun 11, 2007
    Location:
    Singapore
    #11
    as has been said, open up activity monitor and see what is going on.

    my guess is that something is indexing, or something of that sort.
     
  12. Michaelgtrusa macrumors 604

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    Oct 13, 2008
    #12
    Some processes cannot be stopped! I have tried everything! No dice.
     
  13. OldCorpse macrumors 65816

    OldCorpse

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    #13
    Bad News

    I'm afraid this may be a deeper problem - with the OS. SL uses GCD to allocate and distribute tasks to the various cores. Since the problem appears with many applications, and it focuses on one core being overused and the other underutilized, the common denominator in all these is the GCD. That's bad news. It means a fundamental problem with how GCD is implemented. This is no simple bug fix. This is a re-write of a fundamental part of the OS. There may be no cure until 10.7.
     
  14. DrNelly macrumors member

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    Jun 13, 2008
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    NJ
    #14
    I found something really interesting that may or may not have anything to do with these nasty performance issues..

    Tonight, when safari was starting to crawl, and other applications were beach balling for simple tasks as opening an css file, I turned off airport and turned it on again, suddenly safari was smooth again, no more stupid CPU usage, no ridiculous utilization of resources, everything ran like butter again.

    CPU usage actually went down from 65 to 1.5!!!! I repeat this happened immediately after I turned off airport and turned it on again. No restart or log out needed.

    Could all this madness be caused by airport drivers messing with resources utilization management, maybe wrong core thread assignment?

    Please someone else check this out and tell me I'm not starting to see things.

    Needless to say i'm on my new iMac 27.
     
  15. OldCorpse macrumors 65816

    OldCorpse

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    #15
    That's what many people are claiming: Airport is at fault. On the other hand, there are folks who tested the Airport thing, and that does nothing to solve their slowing and sluggishness problems. See the thread.
     
  16. fr4c macrumors 65816

    fr4c

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    #16
    Confirmed! Scrolling through webpages was smooth right off I turned off Airport. CPU usage was also down to 4-5%.

    What the hell is going on....
     
  17. DoFoT9 macrumors P6

    DoFoT9

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    Jun 11, 2007
    Location:
    Singapore
    #17
    just goes to show how useless wireless is, get ethernet :D

    in all seriousness, there must be a serious bug with the wireless cards/coding of them. maybe it is a firmware issue.
     
  18. southerndoc macrumors 65816

    southerndoc

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    USA
  19. JWFerne macrumors regular

    Joined:
    Sep 1, 2006
    #19
    I have last generation 24in iMac... I recently started having slowdowns, but it started occurring after I installed Rosetta for a program that requested it (visualhub). Since then I get random slowdowns and some Quicktime playback is very choppy.

    I haven't reformatted yet, but I do know if I do I will not install Rosetta because I think it was the root of my problems.

    Just throwing out my experience, maybe it correlates with some of these issues popping up.

    Good luck guys!
     
  20. Orthogonal macrumors newbie

    Joined:
    Jan 7, 2008
    Location:
    San Francisco
    #20
    A simple fix for Safari CPU usage problem

    Go into safari preferences and switch off the "Fraudulent sites" alert function in the Security tab.

    That fixed the problem for me immediately.
     

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