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Windows 7 task manager cpu usage history cycles up and down

  • 4 replies
  • 3 have this problem
  • 9 views
  • Last reply by cor-el

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Environment: i7 @2.30 GHz 16 GB RAM Windows 7 Pro SP1 64-bit Firefox 45.0.2 Browser started in safe mode

I've been trying to find out why Firefox consumes so much CPU. After reading several support notes on this subject, I started the browser in safe mode. All extensions, and plug-ins were disabled and only a blank tab is open. I also tried resetting Firefox. Prior to opening the browser, Task Manager CPU Usage History shows very little activity, if any. After starting the browser, Firefox consumes up to 14% of CPU in regular, up-and-down cycles. Is Firefox doing something at regular intervals like pinging a server somewhere? Please see the attached screenshot.

Environment: i7 @2.30 GHz 16 GB RAM Windows 7 Pro SP1 64-bit Firefox 45.0.2 Browser started in safe mode I've been trying to find out why Firefox consumes so much CPU. After reading several support notes on this subject, I started the browser in safe mode. All extensions, and plug-ins were disabled and only a blank tab is open. I also tried resetting Firefox. Prior to opening the browser, Task Manager CPU Usage History shows very little activity, if any. After starting the browser, Firefox consumes up to 14% of CPU in regular, up-and-down cycles. Is Firefox doing something at regular intervals like pinging a server somewhere? Please see the attached screenshot.

All Replies (4)

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I'm also using Win7 64bit & Ffox 45.0.2 and after having installed all the Win7 updates of last week, Firefox is running extremely slow (scrolling, pic loading, click response time, etc) and CPU usage shoots up to 14-15% and more with only 1-2 windows/tabs opened. You also experience slow scrolling? I have asked a Q about this issue yesterday, but no answers yet.

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KVCKKC said

I'm also using Win7 64bit & Ffox 45.0.2 and after having installed all the Win7 updates of last week, Firefox is running extremely slow (scrolling, pic loading, click response time, etc) and CPU usage shoots up to 14-15% and more with only 1-2 windows/tabs opened. You also experience slow scrolling? I have asked a Q about this issue yesterday, but no answers yet.

Hi KVCKKC:

Like you, I've received no answers yet. What's interesting is that for the time being, FF itself is not slow. I'm mainly looking for an explanation of the cyclical nature of the CPU graph. FF WAS very slow when I first started looking into this. I disabled some add-ons, disabled the flash protected mode and made flash always ask. This helped a lot with news sites which are loaded with crap (ads, and come to think of it, crap news too :).

But as I previously stated, I've tried the FF support notes suggesting safe mode but it still cycles the CPU.

One more thing - FF is a cpu hog no doubt. But I had overall W7 issues as well that made everything else slow too. One thing that really helped was setting Windows virtual memory to a custom size instead of letting the OS handle it automatically. I have 16G of RAM. Old school Unix rule of thumb is 2xRAM for swap. I set the initial and max size to 32GB and the system works much better now.

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Boot the computer in Windows Safe Mode with network support (press F8 on the boot screen or hold down the Shift key) to see if that has effect.