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Numbers eats 70% CPU when mouse hovers over document

8118 Views 132 Replies Latest reply: Apr 11, 2013 1:13 PM by Barry Fass-Holmes RSS
  • phineasgage Calculating status...
    Currently Being Moderated
    Aug 6, 2012 5:31 AM (in response to mttl)

    I've reported this to Apple as well. I have a late 2011 MacBook Pro with Mountain Lion and Numbers 2.2 (516) and see 80-85% CPU usage when the mouse is hovering over any table in Numbers, just like maiksd shows.


    Rather than posting a CPU graph, as that's clear now, I thought I'd look at what this does to my machine's temperature. Enjoy this:




    It's obvious that such a commonly used application is causing battery life and heat problems for users. Given that Apple puts a developer armed with a profiler on this, it should be solved soon. It's so easy to reproduce that I'm surprised it wasn't caught before GA. They may may find out that this is not a Numbers problem specifically but something in the OS X display code somewhere. That's not our problem as users, we just call it as we see it.

  • Kees3 Calculating status...

    I have exactly the same problem on my MacBook Pro after upgrading to Mountain Lion. Just sent bug report to Apple.

  • Badunit Level 6 Level 6 (10,775 points)

    My 2009 iMac shoots up to 50-70% also. I never looked prior to Mountain Lion or prior to reading this thread so I can't say in my case if this is something new.

  • Jerrold Green1 Level 7 Level 7 (28,270 points)
    Currently Being Moderated
    Aug 8, 2012 11:34 AM (in response to Badunit)

    I have a system still on Lion and it doesn't load the CPU this way.



  • Steve Jabs Calculating status...

    So when is Apple going to solve this?! If Jobs was still around, I think this wouldn't have happened. This is affecting my business!!!

  • R Saravanan Level 1 Level 1 (0 points)
    Currently Being Moderated
    Aug 17, 2012 8:05 AM (in response to maiksd)

    I have exactly the same problem - and I did exactly the same test (Activity Monitor and nothing else except Numbers).. ..Issue looks to be with Numbers.. I have the latest version (as of yesterday night).. [2012 Air, Mountain Lion, Latest iWork 5.2 -  all that you need to do to reproduce the issue is to open Numbers, create a new sheet and keep Activity Monitor open in the background (focus should be on the Numbers sheet though - when focus moves OUT of Numbers, the CPU usage goes back to normal)]


    For now have gone back to Excel..

  • Steve Jabs Level 1 Level 1 (0 points)

    Hi, have you tried reformatting and reinstalling mountain lion? This is what I have been doing and I am now running mountain lion after a fresh clean install. Only using Safari at the moment and I haven't noticed any spike in activity yet but it's only been seven hours so let's see what happens. Anyone else who tried this route?  How did yours go?

  • Steve Jabs Level 1 Level 1 (0 points)

    Saravanan, just curious ,isn't using Excel a better thing? I mean, Excel is better than Numbers is it not?

  • R Saravanan Level 1 Level 1 (0 points)

    Hi Steve, both applications have their pros and cons.. I tend to use iWork if the document is going to be owned by me completely, and when office collaborating with others from office, I tend to use MsOffice.. I prefer iWork since the output has a significant edge in quality.. ..features-wise, I'd probably say that MsOffice has had much more time to mature (though I dont like the font-rendering by MsOffice on a Mac)..


    Re. Mountain Lion, I dont think I have an option to do a clean install - I wish I could, but till Apple releases a Mountain Lion USB bootable, I dont think I have an option..


    The CPU usage issue is mainly with Numbers only.. Other apps seem to be fine.. (I tend to use Firefox more anyway, so dont know if the issue with Safari exists or not)


    Hope that helps,

  • Steve Jabs Level 1 Level 1 (0 points)

    Thanks, Saravanan.


    Actually, you can clean-install even without Apple releasing a bootable. I did it a couple of days ago. Just google clean install Mountain Lion and you'll find  plenty of help/sites helping you with that.


    When I ran both Numbers AND Safari, that's when the CPU/heat/fan issue starts up.


    Anyone else wanna share their experience?

  • mttl Calculating status...

    I haven't done clean install and everything else works fine except Numbers.


    I'm not planning to do any clean install either and I think that Apple should be the one fixing this for us. I have done the upgrade to Mountain Lion the way Apple prefers and that should be good enough. If something gets broken, they need to fix it.


    It has already taken way too long time to get this fixed considering that Numbers is one of the top apps in the App Store. And I don't understand how this kind of version got released in the first place as it's completely unusable...raises questions about Apple's quality control.

  • Steve Jabs Level 1 Level 1 (0 points)
    Currently Being Moderated
    Aug 19, 2012 1:44 AM (in response to mttl)

    Well, that's what I felt last week but since then I thought I should just try to understand and fix it myself.


    Suit  yourself. You probably have to wait a helluva long time for Apple to do this. Worst case is, that the problem is not Numbers but some other app/plugin/whatever else we installed that is running in the background and is causing this! And during the hopeful wait for Apple you have to contend with the heat, high CPU usage, apps running slow and potentially crashing, annoying noise from the fan (sounding like a PC!), and potentially, the heat could damage your Mac!! I'm not sure if a clean install works for you but to me, so far so good but I have not installed flash or my usual programs yet. I want to take it an app at a time.

  • mttl Level 1 Level 1 (10 points)

    I understand your point but I think it's a little overkill to need to re-install the whole operating system to get a spread sheet application to work correctly, especially when both are Apple's own products. Most of the end users don't even know how to do it. We need to push Apple to keep the quality up because quality is what they are selling to us. Personally, I bought a Mac to avoid all the reinstalling, configuring and tweaking.


    I'm quite sure that it's only Mountain Lion or/and Numbers causing the problem. I have a relatively new Mac and only few apps installed on it, I have done no system level changes either or installed third party drivers. I can't think of anything that could be conflicting with Numbers and causing this kind of behavior.


    I'm also concerned about the heat and simply stopped using Numbers for now. Luckily there is LibreOffice/OpenOffice available for free.

  • stefanradev Calculating status...

    Same story here. But absolutely the same!!!


    Macbook Pro 13", late 2011.


    Screen Shot 2012-08-19 at 17.58.43.jpg


    Only running Numbers causes the fans start crazy. I don't know how we have to wait that Apple solves his problem.


    Is there any answer to somebody from Apple about this case?


    Message was edited by: stefanradev


    Message was edited by: stefanradev

  • mttl Level 1 Level 1 (10 points)

    I have not seen any answer from Apple concerning this.


    I recommend that you send a bug report to Apple by using the Numbers/Provide Numbers Feedback menu. If more people do it, maybe they will prioritize this issue.


    Another option is to write a negative review on the App Store. I'm not sure if Apple reads them but I would assume they do. At least other users will know what they'll get before they buy this version.

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