The problem is almost certainly related to Firefox running Flash. 
Flash is bad on may fronts, not the least is its excessive CPU usage. 
Closing Firefox will fix it, if you can't close it try too minimise the number 
of tabbed windows you have open in Firefox at one time. 

robin

On 09/08/2013, at 10:51, Chris Burton <c...@it.net.au> wrote:

> Hey Ronni
> 
> Thanks heaps for your description on the Activity monitor; it does look quite 
> complicated and I havnt really taken time to understand everything in the 
> displays.
> 
> The number in the 'Page Outs' is 34mb, and has remained so for the past hour 
> while I have been doing various things.
> (I can send you a screen grab of Activity Monitor to have a look at if you 
> like?)
> It shows that 4.4gb (of 8gb) ram is being used, and the VM size is 124gb and 
> Swap used is 187mb. Im not sure what the last 2 of these mean!
> 
> I have not done a big clean up yet, but the work Im doing on the images is 
> part of the process of reducing the number I have on the drive. I have 
> cleaned out some space (to 80gb) at present and will keep going on this. Im 
> hoping to have about 150gb spare when finished. (the drive is a 750gb 7200 
> drive).
> 
> I will also reduce the number of open apps and pages in Firefox.
> 
> I do use Safari occasionally as well, but do you think either Opera or Chrome 
> (or others) are worth considering as alternatives to the hog Firefox?
> 
> 
> Many thanks
> 
> Chris
> 
> 
> Christopher L.K. Burton
> Director
> Western Whale Research
> PO Box 1076
> Dunsborough WA 6281
> Mobile: 0419 199 120
> Email: c...@it.net.au 
> 
> www.souwest.org
> 
> On 09/08/2013, at 9:44 AM, Ronda Brown wrote:
> 
>> Hi Chris,
>> 
>> Yes, any application using 100% CPU will heat up you computer!
>> Running at 100%.... Sheezs... Not good!
>> As well as overheating your computer, heavy CPU (the computer's brains) use 
>> will slow your computer down.
>> 
>> Quit Firefox and any other application that is using a lot of CPU.
>> Quit Applications that aren't actively in use, (try to run fewer 
>> applications at once).
>> In some cases, seemingly idle applications continue to hammer on your CPU 
>> and suck up increasing amounts of RAM- even when you see no evidence of 
>> activity on the screen.
>> 
>> Firefox is a resources hog, I would only use Firefox if you really need to, 
>> use Safari for everyday use.
>> 
>> Open Activity Menu, click System Memory at the bottom of the Activity 
>> Monitor window.
>> Use you computer as you normally do. 
>> As you are working, look at the number in the parentheses beside "Page Outs" 
>> The larger this number becomes, the more actively virtual memory is relying 
>> on slow disk-based swap files.
>> 
>> Did you do the maintenance you mentioned of uninstalling old applications 
>> and cleaning up your MBP, freeing up more Free Space on your Hard Drive?
>> 
>> Cheers,
>> Ronni
>> 
>> Sent from Ronni's iPad4
>> 
>> On 09/08/2013, at 7:44 AM, Chris Burton <c...@it.net.au> wrote:
>> 
>>> Hi Muggers
>>> 
>>> Things just keep happening for no apparent reason and I just cant work it 
>>> out!
>>> 
>>> My MBP has been heating up quite fast of late, the past week I would say. 
>>> 
>>> It has coincided with me doing work with Lr4 and Preview: I have been 
>>> sorting through loads of travel images. However at the same time I have 
>>> Firefox, Mail, iCal and occasionally Word or Excel open.
>>> 
>>> I did some searching online and found a few links to the heating problem 
>>> and one suggested I check Activity Monitor: 
>>> 
>>> it shows Firefox using 100% of CPU!!? Specifically it was Firefox Plugin 
>>> Process (Shockwave Flash).
>>> 
>>> Do you think this would be the cause of the problem? If so can I get rid of 
>>> it, or just close Firefox and not use it?
>>> 
>>> I have done the restart, shutdown, SMC with no change
>>> 
>>> Many thanks for any advice
>>> 
>>> Chris
>>> 
>>> 
>>> Christopher L.K. Burton
>>> Director
>>> Western Whale Research
>>> PO Box 1076
>>> Dunsborough WA 6281
>>> Mobile: 0419 199 120
>>> Email: c...@it.net.au 
>>> 
>>> www.souwest.org
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