Bug 209858 – [GTK] WebkitGTK Layout and Rendering High CPU Usage

• Status: RESOLVED
• Resolution: DUPLICATE
• Component: WebKitGTK

Created attachment 395169 [details]
High CPU Usage on Touchpad Gestures

Performing any pinch touchpad gesture causes a high CPU usage (leading to a sense of hanging up of webpage and unresponsiveness). Attached is a screenshot of WebInspector of what happens when I pinch to zoom in or zoom out. Even in general, scrolling causes a high CPU usage primarily caused by the Layout and Rendering part. In addition, this happens with and without content blocking both. Of course, without content blocking the web browser stutters even more because of a high number of Javascript events.
This is regardless of the website and is a general issue with the browser for a long time.

[Carlos Alberto Lopez Perez]

Which version of WebKitGTK its this?

Can you check what value you have for the epiphany gsetting for hardware-acceleration?

Try running this command:
$ gsettings list-recursively |grep -i epiphany|grep -i hardware-acceleration

Can you try setting it to the value 'always' and restart epiphany?
Can you still reproduce with always?

This is on WebkitGTK version 2.28.0 on Epiphany 3.36.1

I set the hardware-acceleration to ‘always’ and not only did the problem persist but I also got two new problems -
(a) Epiphany crashed the next time I opened it. I did the test after closing it and opening it later on.
(b) Kinetic Scrolling stopped working

So, hardware acceleration didn’t help.

[Carlos Alberto Lopez Perez]

Which value do you have for hardware-acceleration-policy when the bug of high CPU usage triggers? ondemand or never?

[Alice Mikhaylenko]

Duplicate of https://bugs.webkit.org/show_bug.cgi?id=197002?

The pinch zoom is pretty terrible right now, it naively tries to relayout the page on every frame. High CPU usage isn't the problem here, it's actually laggy and unresponsive.

[Michael Catanzaro]

*** This bug has been marked as a duplicate of bug 197002 ***