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PSI: Issues with WebGL

See original GitHub issue

Hi, my website can never be tested I always receive an error. I think I could track it down to one of my packages which uses WebGL + shaders.

There’s a tiny example static website as a showcase for the metaballs-js package.

Reproduction:

Run a test for https://mrtoph.github.io/metaballs-js/
See it fail with Error: Backend Error

Issue Analytics

State:
Created 4 years ago
Reactions:1
Comments:14 (5 by maintainers)

Top GitHub Comments

2reactions

pttskycommented, Jul 10, 2019

I am working on a project which is showing the same issue. Pagespeed is showing either ‘Backend error’ or metrics ‘First CPU Idle’ and ‘Main thread work’ are going crazy. It is using THREE.js. If <canvas> webgl renderer element is not appended into the DOM, these metrics are around 10-30s (here and after “normal scores” 😜 )

I have tested random sites from awwwards claiming to use three.js (https://www.awwwards.com/websites/three-js/)

Here are the scores as of July 2019: https://docs.google.com/spreadsheets/d/1Z9g0pLB3Y-2xdfZXXNtpcUrcjI-NMl8JrJKnK2mXhCU/edit?usp=sharing

2 of 22 got ‘k.o.’ in their desktop score - these are ‘Backend error’ Another 5 of 22 have oddly repeating have 133-137 seconds of first CPU idle / main thread, which looks like a bare timeout value.

It is possible to postpone embedding of <canvas> into the DOM for 1-2 seconds after window.load and get a “normal” score.

Lighthouse is crashing with similar frequency as pagespeed insights.

1reaction

connorjclarkcommented, Jun 25, 2020

unfortunately PSI has to run WebGL in software.

should we dedupe this to https://github.com/GoogleChrome/lighthouse/issues/10334#issuecomment-591127593