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Lowercase "firefox" process using lots of resources

  • 3 replies
  • 2 have this problem
  • 3 views
  • Last reply by FredMcD

Paulwithamac
Paulwithamac
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I recently noticed that every once in a while my Mac gets hot and busy. Checking Activity Monitor when this happens shows that lots of CPU is being used by a process called "firefox" (all lowercase, with no icon, as opposed to the main Firefox process, which is appears as "Firefox" with the first letter capitalized, and the Firefox logo next to it). When I force quit the "firefox" process, the computer calms down. Shutting down "firefox" doesn't seem to have any effect on the main "Firefox" process - the browser stays open etc.

So what is this "firefox" process? Is it actually part of Firefox? If not, what could it be? And why does it keep starting up again every once in a while after I force quit?

I recently noticed that every once in a while my Mac gets hot and busy. Checking Activity Monitor when this happens shows that lots of CPU is being used by a process called "firefox" (all lowercase, with no icon, as opposed to the main Firefox process, which is appears as "Firefox" with the first letter capitalized, and the Firefox logo next to it). When I force quit the "firefox" process, the computer calms down. Shutting down "firefox" doesn't seem to have any effect on the main "Firefox" process - the browser stays open etc. So what is this "firefox" process? Is it actually part of Firefox? If not, what could it be? And why does it keep starting up again every once in a while after I force quit?

All Replies (3)

FredMcD
FredMcD
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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 I Accept the Risk button. At the top of the screen is a search bar.

Paulwithamac
Paulwithamac Question owner
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Thanks for the info.

browser.tabs.remote.autostart.2 was set to true so I changed it. However the "firefox" process appeared again afterwards (I am pretty sure I restarted my browser in between).

However it still seems to me that the behavior of this lowercase "firefox" process is very strange. It always seems to use massive amounts of resources (to the point where computer heats up and the fan gets loud), and quitting Firefox doesn't do anything to stop "firefox". The only way I know how to stop "firefox" is by Force Quit from Activity Monitor.

Also, I can't tell what this second process is actually doing - force quit doesn't have any noticeable effect on the main "Firefox" process or the computer, except giving the CPU resources back.

FredMcD
FredMcD
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Reboot the computer. Then try Firefox again. The problem FF might be a rogue that didn't shut down.