Frank Nestel Reporter
	Description • 7 years ago

User Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:55.0) Gecko/20100101 Firefox/55.0
Build ID: 20170814072924

Steps to reproduce:

I am using both ff55 and ff beta in different but similar environments/addons/tabs etc.
Starting with some ff40, ff became a memory hog, sometimes better sometimes worse. FF54 was so mediocre, so it tooks a few hours in my regular use before it grew from 1GB to 2.7GB and becomming slow. With FF55beta 12 memory usage become great. Now my other environment upgraded from ff54.0.1 to ff55.0.2 and things are again very, very bad. 


Actual results:

While ff55.0.2 is not actually slowing down, it does not need 2 hours of usage to hog its extra 1.7GB and then dies from unsufficient memory.


Expected results:

Memory should have stayed low as with ff55 beta version (and ff56 beta seemed nearly as good when I shortly tested it).

	Andre Klapper
	Comment 1 • 7 years ago

Please enter the address "about:memory?verbose" (with a lower-case "v") in the address bar and attach (using the "Attach File" link above) the output here.

	Kohei Yoshino [:kohei]
	Comment 2 • 7 years ago

Please troubleshoot with Safe Mode: https://support.mozilla.org/kb/troubleshoot-firefox-issues-using-safe-mode

	Marius Coman [:mcoman], Ecosystem QA
	Comment 3 • 7 years ago

Hi Frank,

I have tested this issue on latest Firefox release (55.0.2), on Firefox Beta (56.0b4) and latest Nightly (57.0a1) build. I think I managed to reproduce it in the following way: 

1)I've opened 71 tabs, containing youtube.com, cnn.com, nytimes.com, and IMDB.com;
2)After each page was loaded, I checked the memory usage in "about:performance". 

The used memory from all the processes sumed approximately 4GB. 

Please retest your issue in Firefox beta (55.0b12), take a look in "about:performance" and verify the used memory. Also could you please give us more information regarding the number of tabs which you have open and if possible please list some of the websites you are encoutering this on.

Thank you, 
Marius

	Frank Nestel Reporter
	Comment 4 • 7 years ago

Back from vacation I immediately got ff 55.0.3. and I am using it for a day now. This seems to behave fine again. It all gets very intransparent for me, is there somewhere a (deep) description what things change between 55.0.2 and 55.0.3, creating such a big difference?!

	Andrew McCreight [:mccr8]
	Comment 5 • 7 years ago

There are release notes here:
  https://www.mozilla.org/en-US/firefox/55.0.3/releasenotes/
I can't imagine that any memory-related changes landed that aren't there.

Maybe some addon you use updated to fix a memory issue? I'm going to close this as WORKSFORME.

	Frank Nestel Reporter
	Comment 6 • 7 years ago

Well, close it. Maybe it was a plugin, but I remember reporting memory issues at least for a year and as far as I understood something was quite a bit broken in Firefox memory management for quite a while.