1795525 - WebRenderer using up much CPU and doing heavy re-rendering

Status: UNCONFIRMED

(Core :: Widget: Gtk, defect, P3)

Description

[iYx3Zp8Q08hrNVZCHTYt]

Attachment: repro_1_three_column_mode.png

User Agent: Mozilla/5.0 (X11; Linux x86_64; rv:105.0) Gecko/20100101 Firefox/105.0

Steps to reproduce:

Systems used to reproduce the issue:
1: Debian 11 "bullseye" with FF 102.3.0esr
2: Linux Mint 19.3 with FF 105.0.3

Environment:
We are an enterprise user with a terminalserver setup and 150 clients connected to the server via (x)RDP.

Preparation:
I started two instances of ff using "firefox --safe-mode".
In the first instance i opened "about:processes".
In the second instance i executed the following "Steps to reproduce".

Steps to reproduce:

1. login to https://demo.sogo.nu using username "sogo1" and password "sogo"
2. make sure the window is wide enough to show the "three column mode" (folder area left, email area middle, content area right)
3. make sure, no mails are left in the "Inbox" (delete them, if some are present)
4. change the folder to another one (say "Sent" and go back to "Inbox" (this step seems only necessary if you needed to interacted with "Inbox" in step 3)
5. write a new mail to yourself ("sogo1") (see screenshots "repro_1_three_column_mode.png" and "repro_2_new_email.png")
6. click "refresh" on the email list to show your own new mail
   => WebRenderer is going crazy (see screenshot "repro_3_webrender_going_crazy.png")

See also:
Profile: https://share.firefox.dev/3rVdcto

Actual results:

1. CPU usage rises to an unusual high level
2. the website content (and problably even the ff-window!) seems to be heavily re-rendered in full size mode
3. the RDP-traffic in the whole network rises to really huge levels
4. the clients (thinclients) were flooded with new images using up their ressources for heavy repainting
5. working is nearly impossible
6. power consumption of the server and the client side were doubled or even tripled

Expected results:

1. content: firefox should only render a new frame once as long as no motion/animation is on the website
2. ff-window: the window behavior should not be influenced (e.g. delayed reactions)
3. after refresh (step 6.) no significant CPU usage, traffic and reaction time should be noticable

Comment 1

[iYx3Zp8Q08hrNVZCHTYt]

Attachment: repro_2_new_email.png

Comment 2

[iYx3Zp8Q08hrNVZCHTYt]

Attachment: repro_3_webrender_going_crazy.png

Comment 3

[BugBot [:suhaib / :marco/ :calixte]]

The Bugbug bot thinks this bug should belong to the 'Core::Widget: Gtk' component, and is moving the bug to that component. Please correct in case you think the bot is wrong.

Comment 4

[Martin Stránský [:stransky] (ni? me)]

Can you try to get performance profile?
https://fedoraproject.org/wiki/How_to_debug_Firefox_problems#Firefox_performance_issues
Thanks.

Comment 5

[iYx3Zp8Q08hrNVZCHTYt]

I read this as an explanation how to create a ff profile.

What is the problem with the profile i already created and mentioned above (https://share.firefox.dev/3rVdcto)?