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Firefox randomly starts eating tons of CPU causing lagging and freezing

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Firefox V.35 on Windows 7 64 bit Ok, idk what has gotten into Firefox the last few updates, but it has become incredibly SLOW and laggy. It does NOT matter how many times I clear cache, it has no effect on this. I can be browsing any page.. and at random I will notice the scrolling start freezing every 1 second or so and it gets SLOW and choppy. Typing during this time is just as bad and lags a LOT. I will open Task Manager and notice firefox.exe using 30-70% CPU. CPU usage will keep jumping UP and DOWN .. back and forth. This will keep happening for almost a minute or more. It will stop for awhile then pick up shortly after repeating the same thing over again making browsing horribly slow. It doesn't matter what page I'm on, it still will do this. It doesn't matter if I close tabs, that doesn't help. (yes I have disabled ALL plugins and addons to see if it would help and it does not).

I thought Adobe Flash was the problem, but I was wrong as I had disabled the Flash plugin to see if it would do anything. On another note, Flash also runs SLOW and choppy compared to other web browsers running the same thing, namely ... facebook games. The FPS is ...well.. CHOPPY. I disabled plugin_container.exe and that just made it worse and firefox more unstable.

Anyways, this machine is a laptop and has 4GB of RAM. Everything else on it runs nice and fast, even other web browsers...... except firefox. What's going on with this browser lately? Whatever they did in the last few updates really screwed it up. I since went to using Opera because of how bad it was.

Firefox V.35 on Windows 7 64 bit Ok, idk what has gotten into Firefox the last few updates, but it has become incredibly SLOW and laggy. It does NOT matter how many times I clear cache, it has no effect on this. I can be browsing any page.. and at random I will notice the scrolling start freezing every 1 second or so and it gets SLOW and choppy. Typing during this time is just as bad and lags a LOT. I will open Task Manager and notice firefox.exe using 30-70% CPU. CPU usage will keep jumping UP and DOWN .. back and forth. This will keep happening for almost a minute or more. It will stop for awhile then pick up shortly after repeating the same thing over again making browsing horribly slow. It doesn't matter what page I'm on, it still will do this. It doesn't matter if I close tabs, that doesn't help. (yes I have disabled ALL plugins and addons to see if it would help and it does not). I thought Adobe Flash was the problem, but I was wrong as I had disabled the Flash plugin to see if it would do anything. On another note, Flash also runs SLOW and choppy compared to other web browsers running the same thing, namely ... facebook games. The FPS is ...well.. CHOPPY. I disabled plugin_container.exe and that just made it worse and firefox more unstable. Anyways, this machine is a laptop and has 4GB of RAM. Everything else on it runs nice and fast, even other web browsers...... except firefox. What's going on with this browser lately? Whatever they did in the last few updates really screwed it up. I since went to using Opera because of how bad it was.

All Replies (7)

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Bruce0375 said

Firefox V.35 on Windows 7 64 bit Ok, idk what has gotten into Firefox the last few updates, but it has become incredibly SLOW and laggy. It does NOT matter how many times I clear cache, it has no effect on this. I can be browsing any page.. and at random I will notice the scrolling start freezing every 1 second or so and it gets SLOW and choppy. Typing during this time is just as bad and lags a LOT. I will open Task Manager and notice firefox.exe using 30-70% CPU. CPU usage will keep jumping UP and DOWN .. back and forth. This will keep happening for almost a minute or more. It will stop for awhile then pick up shortly after repeating the same thing over again making browsing horribly slow. It doesn't matter what page I'm on, it still will do this. It doesn't matter if I close tabs, that doesn't help. (yes I have disabled ALL plugins and addons to see if it would help and it does not). I thought Adobe Flash was the problem, but I was wrong as I had disabled the Flash plugin to see if it would do anything. On another note, Flash also runs SLOW and choppy compared to other web browsers running the same thing, namely ... facebook games. The FPS is ...well.. CHOPPY. I disabled plugin_container.exe and that just made it worse and firefox more unstable. Anyways, this machine is a laptop and has 4GB of RAM. Everything else on it runs nice and fast, even other web browsers...... except firefox. What's going on with this browser lately? Whatever they did in the last few updates really screwed it up. I since went to using Opera because of how bad it was.

This isn't firefox problem, its your crappy internet :)

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Could you run Firefox in its Safe Mode for a while as a test? That's a standard diagnostic tool to deactivate extensions and some advanced features of Firefox that can be troublesome on some systems. More info: Diagnose Firefox issues using Troubleshoot Mode.

You can restart Firefox in Safe Mode using either:

  • "3-bar" menu button > "?" button > Restart with Add-ons Disabled
  • Help menu > Restart with Add-ons Disabled

Not all add-ons are disabled: Flash and other plugins still run

After Firefox shuts down, a small dialog should appear. Click "Start in Safe Mode" (not Reset).

Notice any difference over time?


Also, you might want to supplement your regular security software with some of the scanning/cleaning tools listed in our support article: Troubleshoot Firefox issues caused by malware. These on-demand scanners are free and take considerable time to run. If they finish quickly and especially if they require payment, you may have a serious infection. I suggest the specialized forums listed in the article in that case.

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user1192079 said

Bruce0375 said
Firefox V.35 on Windows 7 64 bit Ok, idk what has gotten into Firefox the last few updates, but it has become incredibly SLOW and laggy. It does NOT matter how many times I clear cache, it has no effect on this. I can be browsing any page.. and at random I will notice the scrolling start freezing every 1 second or so and it gets SLOW and choppy. Typing during this time is just as bad and lags a LOT. I will open Task Manager and notice firefox.exe using 30-70% CPU. CPU usage will keep jumping UP and DOWN .. back and forth. This will keep happening for almost a minute or more. It will stop for awhile then pick up shortly after repeating the same thing over again making browsing horribly slow. It doesn't matter what page I'm on, it still will do this. It doesn't matter if I close tabs, that doesn't help. (yes I have disabled ALL plugins and addons to see if it would help and it does not). I thought Adobe Flash was the problem, but I was wrong as I had disabled the Flash plugin to see if it would do anything. On another note, Flash also runs SLOW and choppy compared to other web browsers running the same thing, namely ... facebook games. The FPS is ...well.. CHOPPY. I disabled plugin_container.exe and that just made it worse and firefox more unstable. Anyways, this machine is a laptop and has 4GB of RAM. Everything else on it runs nice and fast, even other web browsers...... except firefox. What's going on with this browser lately? Whatever they did in the last few updates really screwed it up. I since went to using Opera because of how bad it was.

This isn't firefox problem, its your crappy internet :)

My internet is fine. As Istated, it works fine on other browsers, just not Firefox.

jscher2000 said

Could you run Firefox in its Safe Mode for a while as a test? That's a standard diagnostic tool to deactivate extensions and some advanced features of Firefox that can be troublesome on some systems. More info: Diagnose Firefox issues using Troubleshoot Mode. You can restart Firefox in Safe Mode using either:
  • "3-bar" menu button > "?" button > Restart with Add-ons Disabled
  • Help menu > Restart with Add-ons Disabled
Not all add-ons are disabled: Flash and other plugins still run After Firefox shuts down, a small dialog should appear. Click "Start in Safe Mode" (not Reset). Notice any difference over time?

Also, you might want to supplement your regular security software with some of the scanning/cleaning tools listed in our support article: Troubleshoot Firefox issues caused by malware. These on-demand scanners are free and take considerable time to run. If they finish quickly and especially if they require payment, you may have a serious infection. I suggest the specialized forums listed in the article in that case.

I ran in safe mode, problem went away mostly. Restarted FF normally and it still seems ok. If it's one of the Add-ons.. idk which one it is because it isn't acting up right now. The Add-ons that I have are , Adblock Plus, Dark Backgrounds Switcher, Easier Youtube Video Downloader, Keyconfig , RightToClick, User Agent Overrider. The last 3 I usually keep disabled.

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Firefox may have been running slowly because other programs on your computer were eating up your computer's resources, and there wasn't enough left to run it.

Modified by user1194064

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Just-A-User said

Firefox may have been running slowly because other programs on your computer were eating up your computer's resources, and there wasn't enough left to run it.

Nope, that's not it. But thanks. It's firefox loading up the CPU when this happens. I'll still have well over 2.5GB of RAM free and this still happens at random. It hasn't been happening that often. I have to leave it open for a while, sometime a few hours before it starts doing this nonsense on a page. I need a good screen recorder so I can capture this.

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Bruce0375 said

Just-A-User said
Firefox may have been running slowly because other programs on your computer were eating up your computer's resources, and there wasn't enough left to run it.

Nope, that's not it. But thanks. It's firefox loading up the CPU when this happens. I'll still have well over 2.5GB of RAM free and this still happens at random. It hasn't been happening that often. I have to leave it open for a while, sometime a few hours before it starts doing this nonsense on a page. I need a good screen recorder so I can capture this.

How powerful is your CPU? Click the Start menu, right click Computer, click "Properties", then give us this info: http://s29.postimg.org/qivcp1mh3/image.png

Also, give us some info about the processes running on your PC. Download Process Explorer by clicking here, extract the contents of the zip file that you downloaded, double-click the extracted procexp.exe, and in Process Explorer, click File>Save As. Upload the file that you saved using mega.co.nz, and send us the link to the file. The file simply contains info about the running processes on your PC, and we can determine if low RAM or too much CPU usage is the problem.

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Bruce0375 said

Just-A-User said
Firefox may have been running slowly because other programs on your computer were eating up your computer's resources, and there wasn't enough left to run it.

Nope, that's not it. But thanks. It's firefox loading up the CPU when this happens. I'll still have well over 2.5GB of RAM free and this still happens at random. It hasn't been happening that often. I have to leave it open for a while, sometime a few hours before it starts doing this nonsense on a page. I need a good screen recorder so I can capture this.

If we determine that the problem isn't due to an outdated CPU or insufficient RAM, use Firefox for a few days without any add-ons. If the problem doesn't happen after you've done that, it's definitely an add-on. As a last resort (if we can't figure out which add-on is causing the problem), we can try a refresh of Firefox or a complete reinstall.

Modified by user1194064