Mozilla Admits that Firefox has CPU Usage Problems
Is your ultraportable overheating while surfing the web? As odd as it sounds, the culprit could be Firefox rather than a hardware issue. No, really, check out what one of Mozilla's support pages has to say on the matter.
"At times, Firefox may require significant CPU resources in order to download, process, and display web content," Mozilla states in a document titled "Firefox consumes a lot of CPU resources."
As CNet notes, this is a real problem that users are reporting, such as this Dell Mini9 owner. So what's the solution? Short of switching to a different browser, Mozilla recommends downloading and installing the latest version of the Flash plugin, which might help with Flash heavy sites like YouTube, and installing Flashblock, which allows end-users to selectively enable and disable Flash content.
Depending on when and where the high CPU usage kicks in, Mozilla also recommends updating the Adobe Reader plugin, configuring Firefox to open PDF documents outside of Firefox, and installing NoScript.
Have you noticed any unusual CPU activitiy or overheating woes while running Firefox? Tell us in the comments section below..

Image Credit: cypherhackz.net
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DasHellMutt
November 25, 2009 at 12:59pm
I will never understand the level of devotion and respect Firefox gets. Its second rate at best and always has been. Its always been slow and a resource hog. Not to mention the compatability issues. None of that is supprising given its Netscape roots. I much prefer IE. I never have a problem with it. I don't need a browser that doesn't work with half the web content. And IE 8 is way faster than firefox. Now if you want something astonishingly fast Chrome is it but I found it too stripped down for my tastes and I don't really like the UI design. I'll stick with trusty old IE thank you.
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NeoTifa
November 25, 2009 at 6:46am
Just this morning I was exclaiming via Twitter how my Vista laptop only installs updates and restarts when I'm in a hurry and have to do something in the morning, so that also means I have to restart FF. Not only does it take 10 freaking minutes to start up, it pulls up like 3 instances of the browser. :( It also lags everything out, and even after starting it, it doesn't respond half the time. I thought it was just my computer or that it was redownloading all the temp files I deleted. :/
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foamcup
November 23, 2009 at 8:29pm
Try a different browser, you have Internet Explorer, Safari, Chrome, Chromium, and Iron that you can try out.
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SURF2DI4
November 23, 2009 at 2:47pm
I had to switch my spouse's dual core for a quad core. Just so she could get work done on her computer. i would slow to a crawl even with an E6300 core 2, it now has a q6550 quad.
karl
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aviaggio
November 23, 2009 at 2:22pm
I always have lots of problems with Firefox on my 3-year old laptop. CPU usage is all over the place, many YouTube videos are hard to play, and it consumes a ton of RAM. Page rendering often shoots CPU usage up to 80%+ and it's almost impossible to scroll down while a page is loading. I have to wait for it to finish before Firefox becomes responsive again.
I could probably trim it down if I disabled all the add-ons, but then what's the point? The reason I use Firefox is because of the functionality from the add-ons. Otherwise I'd probably be using Chrome.
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jhaygamba
November 23, 2009 at 2:05pm
Yes, Mozilla uses and had problems with CPU Usage. I used to open more than 20 tabs in a row (each FF window). Sometimes I noticed, when it reaches for about 40 tabs, Firefox stops responding for more than a seconds or a minute. As I check the task manager, it uses more CPU usage more than Photoshop CS4. About 1GB of memory usage.
But, I still love using Firefox more than any browser. :)
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firesoul1
November 23, 2009 at 2:03pm
Im using firefox right now with 10 open tabs. Maximum PC, ESPN, FOX Sports, Adobe, BBC, Google, Youtube, Newegg, The Consumerist, and Ars. Also im running AMD's Power Monitor with Cool and Quiet enabled and Task Manager (WinXPPro). Both show at the very minimum of 2% CPU usage. at the time of this writing i have monitored both progams and none have shown to exceed 10% CPU usage. this is may hardware.
AMD Phenom 8450 Tri-Core 2.1 Ghz
OCZ Reaper 4GB DDR2 800 @ 1.90V
ATI/VisionTek HD 3650 512MB PCIe 16X
Western Digital Caviar Blue 250GB @ 7200RPM SATA
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firesoul1
November 23, 2009 at 2:09pm
updare: only when refreshing several pages at once is when it works more and while scrolling up and down really fast. But never stayed above 50%
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WFUJay
November 23, 2009 at 2:15pm
Your hardware is also 100x better than what's in the Dell Mini that the lady referenced in the article is complaining about.
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Zazubovich
November 23, 2009 at 1:56pm
No matter how you slice it. Nothing makes me feel like I'm using a hayes modem on dialup with a 386 than having a lot of Firefox tabs open. Except trying to do it with Explorer or Chrome. Firefox gave us the ability to do something (tabbed browsing), now they have to refine how it is done to stay on top.
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Deanjo
November 23, 2009 at 4:22pm
Firefox was far from the first to offer tabbed browsing. NetCaptor and Opera had tabbed browsing back in 2000, that's a full 4 years ahead of FF.
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routine
November 23, 2009 at 1:48pm
I have a solution:
Use Chrome instead; you click the icon and Chrome pops right up, no waiting. When I click Firefox I wait, and wait, and wait, and finally it opens up. IE8 is faster than Firefox.
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nduanetesh
November 23, 2009 at 2:24pm
I'm a Chrome user as well, and when I'm telling people about Chrome vs. Firefox, I use this analogy:
Chrome is like a sportscar: it's super fast, but a little stripped down and sparse.
Firefox is like a luxury sedan: via extensions, it has all the bells and whistles you could ever want, but if you're looking for speed, look somewhere else.
It's actually kind of a shame. I remember when firefox was the super fast browser and I wouldn't have thought about switching to something else.
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immersive
November 23, 2009 at 1:47pm
What good is a high end cpu and ram if you dont get to use it? Now if your overheating I could see switching though. I still love firefox and I think it will be a long time before I switch to something else.
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WFUJay
November 23, 2009 at 1:44pm
She's whining about CPU usage with 20+ tabs open on Firefox constantly?? Seriously? What does she expect.....it's a Dell Mini, not an i7 ffs. Most Mini's have single core ATOM processors...this lady can't be serious.
Is it really necessary to run that many tabs anyway? Considering what's running on each tab (flash, scripts, adobe reader possibly among others) it's not surprising that the CPU usage is that high on such a limited system.
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Obsidian
November 23, 2009 at 1:33pm
As a web developer I use FireFox a lot, my whole team does. But it also causes a LOT of memory and CPU usage. It's probably responsible for 70% or more of the (user-induced) reboots we do just to entirely clear out the memory and process tree.
Task manager shows FireFox is eating up over 313 MB of memory right now, and that's EASILY the largest usage on my list. IE, with just as many windows open is at 230 MB.
Some of this is due to the plugins I like to use for FireFox, like ColorfulTabs, FireFTP, ColorZilla, Adblock Plus, and probably a few others I have turned off for speed, but I'm sure they still take up resources :P
It's impossible to know exactly but it could be partially user-induced because FireFox is more friendly for what I actually WANT a browser to be like, and lucky for a lot of us we can load nice plug-ins/ add-ons very easily.
But yes, to answer the question, it's a resource hog sometimes, and a memory hog ALL the time.
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lien_meat
November 23, 2009 at 4:27pm
I'm a web programmer, use firefox alot too...but I'm confused why you would reboot just to clear ff out of memory? why not just close firefox and re-open it? That always fixes everything for me...and I really only have to do that after a week or more usually (when it uses about 400mb ram). As for it being a memory hog, I find that it depends on javascript and flash more than anything else. I've actually compared opera 10 and chrome vs ff3.5, and they actually DO do about the same for memory if you use them exactly the same for a long time. I can't comment on IE, as I rarely run it (I do mostly php/python with mysql development and some ajax sometimes too, so I don't play with browser dependent issues so much that I have to).
Even if firefox is really bad with memory and cpu, I've usually got enough to spare, even on my crappy 1.6core2 duo laptop with crap intel graphics.
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V-mateika
November 23, 2009 at 1:09pm
I've had 68% plus usage from firefox before, I have 5+ tabs open at one time, sometimes simultaneous loading, but Google Chrome never does that for me. I have a Core 2 Duo 3GHZ dual core in my notebook it should not ever hit 68%. I'm switching to google chrome, it's very fast, much more than firefox for me, and I don't need to bother with tweaking like I do with firefox.

















