Return to Level1Techs.com

Firefox multithreading performance trouble

Got myself a new display and find myself with ample space to fill my screen with lots and lots of windows (5120x1440).

Before I used the tabs within a single Firefox window and never used more than one tab at a given time just because resolution wasn’t suitable to run multiple browser windows.

When watching a video on YT on e.g. “Firefox 1”, all other tabs on “Firefox 2” slow down really bad. Smooth scrolling gone and a second video resulting in dropped frames and overall worse responsiveness.

I can rule out hardware, because when running two different browsers (Firefox+forked Firefox), everything is fine. I also checked Firefox settings for the performance options and also made sure “dom.ipc.processCount” is set correctly in about:config.

In my KDE desktop I can start applications either in “new window” or “start new instance”, but pstree doesn’t show any difference and didn’t resolve any problems.

Any help? I can use multiple different browsers for each window I want to use as a workaround, but that’s not an elegant solution in the long term.

btw. 6 weeks on Linux now. Love it!

Try GNOME. Its a hog on resources, i know, but GTK seems to fare better with scteen issues like these. You could always try it on a bootable USB…

EDIT: Not to shill on GNOME too much but i was fine for me for 1080p, it could be just as bad for your monitor size. I think Qt based stuff has some compositor issues but i am unsure.

I am on the i3 window manager. I have two instances of Firefox open, in one I have YouTube running, in the other the Forum. Works flawlessly. No stutter. I wanted to ask you about your situation. I do not understand what you mean with Firefox 1 and 2 on the one hand an forked on the other hand. I do not know what you mean with that terminology. In my case I have two separate Firefox windows open and everything works.

I think what was meant was one came from the official repo and another came from the Mozilla official binary from their website. Or something like that

I used the numbers to name the two firefox windows I have opened. Two windows side-by-side. But then I installed a forked firefox (to check if my system is the problem or firefox) and opened both the standard firefox and the forked one, and suddenly no performance problems anymore. I only get bad performance when I start two windows of the same browser.

Version is 92.0.1, the latest and greatest

I think it is a problem with your graphics stack. I am on Firefox 92.0.1, too and can’t replicate this behavior. Which distribution and window manager are you on currently?

OS: Garuda Linux
Kernel: 5.14.7-zen1-1-zen
DE: Plasma 5.22.5
WM: KWin

c&p from my neofetch :slight_smile:

On Garudas download page, which ISO did you choose?

The full ISO with like 7GiB. But that was 6 weeks ago…I’m far beyond a fresh install.

Somethings wrong with you installation or your graphics stack. I installed Garuda with KDE on a notebook with Intel and Nvidia GPUs and was able to play two Youtube videos, in two different Firefox windows, simultaneously, while scrolling through Reddit, without stutter.

1 Like

Thanks. I wanted to distro hop anyway, now that I’m more familiar with modern linux (Garuda was recommended to me and served me well into my first steps back into linux).

Got some other minor things that bother me atm. I guess I check out Manjaro XFCE for the time being. Got around two months to find a lasting home until my new system arrives. Made some good progress so far :slight_smile:

1 Like