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Windows7 task manager shows Three copies of firefox running in processes. Why?

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  • Last reply by FredMcD

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With Firefox running, after a few minutes, task manager in Windows7 shows ALL of my CPU resource being used. When I check processes there are THREE copies of firefox running and memory usage for this one program is often over 1GB, despite there being only one tab open! Why is Firefox so hungry for resources. It's a PITA. Has anyone got a reason why this happens, and if it shouldn't be happening then a fix for it? Thanks.

With Firefox running, after a few minutes, task manager in Windows7 shows ALL of my CPU resource being used. When I check processes there are THREE copies of firefox running and memory usage for this one program is often over 1GB, despite there being only one tab open! Why is Firefox so hungry for resources. It's a PITA. Has anyone got a reason why this happens, and if it shouldn't be happening then a fix for it? Thanks.

All Replies (2)

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sometimes when multiple copies of programs are running in mem, its due to some kind of hardware problem.

for example, the mouse may be failing. or the harddrive masterfile table, mft, is unindexed. in which case, hard drive tuning up might not be a bad idea.

what you can try is to launch firefox without the mouse, and see if multiple copies are loaded.

you can also try the above via safemode as well.

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More than one process is normal for the current Firefox. http://www.ghacks.net/2016/07/22/multi-process-firefox/

Multi-process Firefox is codenamed "e10s". https://wiki.mozilla.org/Firefox/multiprocess


Try to disable multi-process tabs in Firefox. You can disable multi-process tabs in Firefox by setting the related prefs to false on the about:config page.

browser.tabs.remote.autostart = false browser.tabs.remote.autostart.2 = false

http://www.ghacks.net/2016/07/22/multi-process-firefox/

Type about:config<enter> in the address bar. If a warning screen comes up, press the Be Careful button. At the top of the screen is a search bar.