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Excessive Firefox instances taking up 55% of my CPU power

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  • Last reply by cor-el

kcourcey1
kcourcey1
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I was looking at an article on CNN when the fan in my PC started winding up to its top speed. I pulled up the Task Manager and found that 29 instances of Firefox were running simultaneously! Is there a way for us to limit the number of Firefox instances so that it won't completely paralyze my computer? I remember this happening a couple of years ago and I moved to a different browser, but I'd really rather get this under control than switch browsers.

I was looking at an article on CNN when the fan in my PC started winding up to its top speed. I pulled up the Task Manager and found that 29 instances of Firefox were running simultaneously! Is there a way for us to limit the number of Firefox instances so that it won't completely paralyze my computer? I remember this happening a couple of years ago and I moved to a different browser, but I'd really rather get this under control than switch browsers.

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cor-el
cor-el
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You will see more Firefox processes running than before and when Fission is enabled you can no longer modify the number of content processes in "Settings -> General -> Performance". You can inspect the current Fission state on the "Help -> More Troubleshooting Information" (about:support) page (search for Fission and check the Remote section further down). Fission is about a new site isolation architecture in Firefox.

You can control Fission via fission.autostart on the about:config page, true to enable and false to turn it off.

  • about:config => fission.autostart = false

You need to close and restart Firefox after modifying the setting to make changes effective.

You can open the about:config page via the location/address bar. On the warning page, you can click "Accept the Risk and Continue" to open about:config.

Firefox has a Performance section in the General tab of the about:preferences page.

  • Settings -> General -> Performance

If you remove the checkmark on "Use recommended performance settings", you will see more settings (hardware acceleration and if Fission is disabled, multi-process settings).