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How do I get Firefox to behave as if I have less RAM?

  • 6 replies
  • 2 have this problem
  • 23 views
  • Last reply by Pj

vefeve
vefeve
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I use Firefox on Windows and Firefox tries to use too much of my system's RAM. I know this is for performance reasons BUT there is very little performance gain. This behavior is fine for users who only run Firefox and little else. BUT I use other memory intensive apps not only Firefox so Firefox using up lots of my RAM is very bad for my use case.

On a system with lots of RAM when I use gmail and Facebook on Firefox the firefox processes can bloat to more than 2.5GB! And it actually seems to start getting slower at that point.

But if I run Firefox in a Windows Virtual Machine with only 1.5GB RAM and start using gmail and Facebook a lot the largest firefox process only gets to a max of 750MB. So that is proof that Firefox can actually work with less RAM without crashing.

How can I get Firefox to behave as if the system has less RAM (e.g. just set a max RAM limit) without to resorting to running it in a VM? I have tried stuff like Process Governor but Firefox tends to crash when it hits the limit instead of running the GC. In contrast on a virtual machine with less RAM Firefox doesn't seem to crash and just uses less RAM.

Is there also a way to get Firefox to automatically do what the about:memory "Minimize memory usage" button does, when it starts to go past a memory usage threshold?

I use Firefox on Windows and Firefox tries to use too much of my system's RAM. I know this is for performance reasons BUT there is very little performance gain. This behavior is fine for users who only run Firefox and little else. BUT I use other memory intensive apps not only Firefox so Firefox using up lots of my RAM is very bad for my use case. On a system with lots of RAM when I use gmail and Facebook on Firefox the firefox processes can bloat to more than 2.5GB! And it actually seems to start getting slower at that point. But if I run Firefox in a Windows Virtual Machine with only 1.5GB RAM and start using gmail and Facebook a lot the largest firefox process only gets to a max of 750MB. So that is proof that Firefox can actually work with less RAM without crashing. How can I get Firefox to behave as if the system has less RAM (e.g. just set a max RAM limit) without to resorting to running it in a VM? I have tried stuff like Process Governor but Firefox tends to crash when it hits the limit instead of running the GC. In contrast on a virtual machine with less RAM Firefox doesn't seem to crash and just uses less RAM. Is there also a way to get Firefox to automatically do what the about:memory "Minimize memory usage" button does, when it starts to go past a memory usage threshold?

All Replies (6)

WestEnd
WestEnd
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Try this.

https://support.mozilla.org/en-US/forums/support-forum-contributors/713193#post-74840

Modified by WestEnd

StevenCee
StevenCee
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His method wouldn't necessarily find out what the problem is. If the problem exists, even after uninstalling everything, then reinstalling, it doesn't prove it's not the browser at fault. That's not logical... If Firefox is the problem, then it would still be the problem, even when freshly installed.

If the newly installed browser works without eating RAM, then it would prove that something about the browser uninstalled was causing the problem. But if the problem still exists, you wouldn't conclusively know if it's Firefox, or something else that's causing it.

Pj
Pj
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vefeve said

I use Firefox on Windows and Firefox tries to use too much of my system's RAM...

There are 'tricks' in the About:Config area to set/adjust various Cache and Memory settings. I don't know if there are any detailed instructions or info on how to use/adjust all these, other than what's been posted here before with some of these adjustments.

Otherwise, I have turned-off Multi-Thread Processing and turned-off 'Hardware Acceleration' to help my FF Memory/RAM usage. Some Extensions block ads and other info to help reduce memory-eating sites.

~Pj

Pj
Pj
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  • Update:
  • Huge Memory Hog Session after Disabling and re-Enabling ABP (Ad Block Plus). My FF takes anywhere from 7 to 11 minutes to startup and stabilize before I can navigate with it. (Granted, I have over 900 Tabs with 5 or 6 browser windows - my main window has over 800 Tabs - not all active at once.)
  • I restarted FF in 'Safe Mode' and FF started up and was ready to go in less than 2-minutes!
  • After using ABP for years, I now removed it. This so far appeared to have been the main problem with Memory and probably my CPU bloat at times, as the browsing session goes on for several days or more before I needed to restart the browser (and sometime the computer, also).
  • I'm now using uBlock and will see how this one goes.
  • Memory at this moment is around 3.50GB (of 8GB). It's off to a good start, so far.


~Pj

vefeve
vefeve Question owner
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OK my workaround is to use the 32 bit version of Mozilla Firefox (uninstall 64 bit, install 32 bit, no other changes). Now all the Firefox processes tend to keep below about 1GB while behaving pretty normally even with many tabs and the exact same extensions and profiles. Performance is fine. CPU usage might be high sometimes but it still works better than when the 64 bit Mozilla bloats up to many GBs and starts getting slow.

Too bad the Mozilla developers don't make it easy to just set a simple memory limit, and/or set an automatic garbage collection interval and threshold.

Pj
Pj
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vefeve said

...Too bad the Mozilla developers don't make it easy to just set a simple memory limit, and/or set an automatic garbage collection interval and threshold.
  • Well, there are ways to work some of the Memory and Cache, but I don't know where there might be any full docs/info on how to adjust and use all of these, other than what's been posted here with the About:Config modifications.
  • Update: On my uBlock Extension vs no more ABP (AdBlock Plus). Memory is behaving better. It doesn't top-out as fast, so I can go longer before Exiting (Control-Shift-Q) and resuming my sessions. (And every so often, ReStarting my computer.)
  • Also, once I reduce my main browser's Tabs from 862 (Ouch!) down to something less ridiculous, I should have less Memory choking. Today, I Quit and ReStarted my FF, and it only took about 3-minutes to load-up and be ready to navigate. If I still had ABP, it would've been 10-to-12 minutes.
  • I'm still on FF 61.0.2, and I read that FF 63 has some more 'Memory' improvements. Can anyone notice this improvement with their Windows-7 Desktop?


~Pj

Modified by Pj