Lags when I scroll or touch a button

[StendhalSyndrome]

Version: 1.46.1
Commit: cd9ea64
Date: 2020-06-19T10:53:55.306Z
Electron: 7.3.1
Chrome: 78.0.3904.130
Node.js: 12.8.1
V8: 7.8.279.23-electron.0
OS: Linux x64 5.4.0-39-generic (Ubuntu LTS 20.04)

Steps to Reproduce:

1. Open Visual Studio Code
2. Scroll/touch a button etc...

It's like very low FPS, it's jerky. I already used "window.smoothScrollingWorkaround": true.
When i minimize the window, everything go back to normal (still lags a litlle bit). It does the same thing on Atom, but not on Discord, so it's not a problem common to all electron-app. I'm using an external mouse.

Does this issue occur when all extensions are disabled?: Yes

[galich]

seems to be related to #97151

code --disable-gpu helped me, but it's not the right answer to the problem

[deepak1556]

@StendhalSyndrome can you provide the performance profile with the following steps,

• open code --disable-extensions
• Command Palette > Toggle Developer Tools
• Go to the Performance tab
• Click record profile
• Perform some scrolling that shows the lag
• Stop profiling
• Save the profile

[deepak1556]

Also what does the fps meter from devtools indicate when you scroll, you can open the fps meter by

Developer Tools > Options > More Tools > Rendering > Fps meter

[galich]

@deepak1556 here is mine from Windows

Profile-20200715T142209.zip

[deepak1556]

@galich thanks for the profile, some quick points

• Each mouse input event are more >1s and the time it waits on the main thread is not even half as close to the total time, indicating something else from script execution is blocking stuff

• Checking all the long tasks (tasks highlighted with red label) reveal that majority of the time is spent is composition layers, which indicates issue with GPU

Can you share your gpu info, also are you using an external mouse ?

The next step would be to perform an internal trace of chromium to find out what exactly is happening at the GPU layer, currently vscode only supports startup chromium tracing, will need to update it before proceeding further. Can you open a new issue to continue the conversation. The authors' issue is on linux which might have different cause, don't want to create noice here.

[galich]

@deepak1556 i've filed a new one as requested

#102661

[deepak1556]

thanks @galich

[StendhalSyndrome]

Mine:
Profile-20200716T165443.zip