Hey there!

See the following website on what to do to fix the performance issue:

https://support.mozilla.org/en-US/kb/firefox-uses-too-much-memory-or-cpu-resources

Hope I helped!

Kind regards,

Bithiah

Thanks for the reply.

My point was FF doesn't seem to unload unused tabs as stated in the update release notes. May be it's configured to do to so only upon system resources reaching critically low levels. How FF determines low resources on a wide variety of system configurations across the user-base is the bone of contention here. As mentioned, I've not seen any noticeable positive impact on my machine at least.

Google Chrome (which I don't use these days) does seem to handle the Memory consumption aspect reasonably well but is quite high on CPU usage.

Anyway, happy to have learned about the "Minimize Memory Usage" tab in about:memory in the link you provided. Quite useful to clear out memory on a need-basis. Sadly, upgrading RAM/Computer is not an option :p.

Haha sorry I couldn't be more useful!

Hey there!

If your problem is solved, please mark any answer as a solution to let others know this thread is finished. Thanks!

Kind regards,

Bithiah

I understand the thread's marked solved (by me), but the recent FF update (Ver: 94) has entirely taken away the "Content Process Limit" from the settings. Now that's one less option at the end user's disposal in controlling how much Memory FF consumes.

Changing the "dom.ipc.processCount" (in about:config) to a respectable count seems to have little effect in terms keeping a check on the process limit, with the browser spawning no less than 23 separate processes for a mere 12 open tabs, and in the process gobbling up the best part of 30-40% of the total RAM allocation.

The only workaround is to use a third party add-on (Auto discard tabs) to restore some sanity. I sincerely hope and pray FF doesn't go the same way as other proprietary browsers (Read: EDGE, Safari etc) in tying the hands of us users by limiting much needed options with every future update.

Thank you

There has been a slow rollout of Fission (Site Isolation) in Firefox, so if you notice you have more content processes than in the past then you might have been selected to participate in this experiment and have Fission enabled. Fission is about a new site isolation architecture in Firefox and you will see more Firefox processes running than before and when Fission is enabled you can no longer limit the number of content processes in Settings or via dom.ipc.processCount on the about:config page. You can check the current Fission state on the "Help -> More Troubleshooting Information" (about:support) page (search for Fission).

• https://hacks.mozilla.org/2021/05/introducing-firefox-new-site-isolation-security-architecture/

(I've unmarked the solution since you didn't mark a reply that has a solution; if you intend to close the thread then mark your own reply as the solution)

@ cor-el, Thanks for the heads up on the site isolation thing. And, yes the Fission feature is indeed enabled in my case, but, I don't see any way to disable it (not that I intend to do so immediately).

Whist we appreciate the need for the same, what I fail to gather is how the number of content processes is nearly double the no. of open tabs (including a few add-ons). If not for the 'Auto Discard Tabs' I mentioned, the RAM taken up by FF easily brings my system to a crawl.

The situation could be mitigated if FF performed as claimed below: When available system memory is critically low, Firefox on Windows will automatically unload tabs based on their last access time Sadly this is not the case either.

Anyway I'll leave the thread open for now until I see some progress.

Edit: I also have Multi Account Containers enabled on my profile. Not sure if it has anything to do with the increased content processes.

Thank you

You can set fission.autostart = false on the about:config page to opt-out of this experiment and disable Fission.

• https://support.mozilla.org/en-US/kb/about-config-editor-firefox

See also the about:unloads page.

• you can open "about:" pages via the location/address bar
  this "about:" protocol is used to access special pages

Thanks again... Made the mistake of disabling Fission on the Troubleshooting page itself. Anyway nice to have learned "about:config" is the go-to when it comes to looking for answers.

Edit: Just for my understanding: Is Firefox's Site Isolation a built in alternative to "Multi Account Containers" add-on, or is MAC just a rudimentary implementation of what Site Isolation provides in terms of safety. Is one better than the other? And, does running both together explain the unexpectedly high content processes, as in my case.