Bad qtwebengine performance with lima

[WArnauer]

Hi!

I am testing the web performance with lima on a Lime2(A20) using meta-qt6 and the quicknanobrowser example. Building was pretty much straight forward with this settings(there is more but I think the rest is not relevant): MACHINEOVERRIDES .= ":use-mailine-graphics" DEFAULTTUNE = "cortexa7hf-neon-vfpv4" IMAGE_INSTALL:append = " qtwebengine "

With default settings(QTWEBENGINE_CHROMIUM_FLAGS="--no-sandbox") it's nearly unusable. Images are flickering during loading and scrolling also causes the site to jump around. Can send a video if needed. After messing around with the chromium flags I found that --disable-gpu-compositing avoids this issue and the browser becomes usable.

Performance is still worse than my old setup which is an all custom built(no yocto) 5.4.x kernel + mali-blobs + Debian Buster + Qt 5.12.x.

Any idea how to speed this up with build options, chromium flags... ? Or is it expected that lima is slower than the old mali-blobs?

Thanks, Wolfgang

[nandra]

@WArnauer just found out in my notes that running chromium using lima I was using this: chromium --no-sandbox --start-maximized --kiosk --use-gl=egl https://youtube.com so maybe --use-gl=egl can help? Just my 2 cents

[WArnauer]

There are some init parameters already set, including the egl. Not sure if any of the other messages(locale, cursor) may cause performance issues.

QTWEBENGINE_CHROMIUM_FLAGS="--no-sandbox" /config/quicknanobrowser https://orf.at
Detected locale "C" with character encoding "ANSI_X3.4-1968", which is not UTF-8.
Qt depends on a UTF-8 locale, but has failed to switch to one.
If this causes problems, reconfigure your locale. See the locale(1) manual
for more information.
QStandardPaths: XDG_RUNTIME_DIR not set, defaulting to '/tmp/runtime-root'
Failed to move cursor on screen LVDS1: -14
Failed to move cursor on screen LVDS1: -14
qt.webenginecontext:

GL Type: egl
Surface Type: OpenGLES
Surface Profile: NoProfile
Surface Version: 2.0
QSG RHI Backend: OpenGL
Using Supported QSG Backend: yes
Using Software Dynamic GL: no
Using Multithreaded OpenGL: yes

Init Parameters:
  *  application-name Quick%20Nano%20Browser
  *  browser-subprocess-path /usr/libexec/QtWebEngineProcess
  *  disable-composited-antialiasing
  *  disable-features ConsolidatedMovementXY,InstalledApp,BackgroundFetch,WebOTP,WebPayments,WebUSB,PictureInPicture
  *  disable-setuid-sandbox
  *  disable-speech-api
  *  enable-features NetworkServiceInProcess2,TracingServiceInProcess,OverlayScrollbar
  *  enable-threaded-compositing
  *  enable-viewport
  *  in-process-gpu
  *  no-sandbox
  *  use-gl egl

Detected locale "C" with character encoding "ANSI_X3.4-1968", which is not UTF-8.
Qt depends on a UTF-8 locale, but has failed to switch to one.
If this causes problems, reconfigure your locale. See the locale(1) manual
for more information.
Detected locale "C" with character encoding "ANSI_X3.4-1968", which is not UTF-8.
Qt depends on a UTF-8 locale, but has failed to switch to one.
If this causes problems, reconfigure your locale. See the locale(1) manual
for more information.

[nandra]

Don't think so it can cause an issues.

[nandra]

@WArnauer I've tried mickledore and chromium using wayland and performance seems to be fine (didn't do any measurements though). Did you check that pls? Thanks.

[nandra]

@WArnauer any update on your end please? Thanks.

[WArnauer]

I didn't manage to get the combination of mickledore + chromium + wayland working with my setup and had to pause this project for now. Still planing to test QtWebengine with Wayland as backend at some point but no planned date yet.

[nandra]

OK will close it for now, then we can re-open. Thanks!