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After testing this project with Unity 2023, 2022, and 2021, the issue does not happen there. I then tested it with 2020.3 and did indeed repro it. It seems that between 2020.3 and the next versions the profiler sends data faster and the buffer is enough. A workaround I tried for my 2020.3 test that succeeded is to follow the error message in the console that says: "Please use Profiler.maxUsedMemory API or -profiler-maxusedmemory command line parameter to increase maximum allowed memory usage." I did that by modifying the Module object in the build's loader.js file and setting the flag with a larger value as an argument like this: var Module = { arguments: ['-profiler-maxusedmemory', 100000000], canvas: canvas, webglContextAttributes: { ... } }
Reproduction steps:
1. Open the attached project ("case_1265204-WebGL Profiling.zip")
2. Open the repro scene ("SampleScene")
3. Open Profiler tab
4. Make a WebGL build (development, AutoConnect enabled) and run it
5. Go back to the Editor and inspect Profiler
6. (if no repro) Restart the build inside browser
Expected result: Build data is being flushed to the Editor and displayed in the Profiler tab
Actual result: Build data is not displayed in the Profiler tab and "Unknown profiler sampler in thread block: 578" error is thrown
Reproducible with: 2019.4.7f1, 2020.1.2f1, 2020.2.0a20
Couldn't test with 2018.4 (Graphy errors after downgrade)
Notes:
1. The issue does not reproduce on an empty project
2. The repro project is also using Graphy plugin for in-build profiling
3. The following warning is being thrown when issue is reproduced:
"Autoconnected Player Stopping profiler. Profiler is not able to flush data to a file or socket and exceeded maximum allowed memory for buffering.
Please use Profiler.maxUsedMemory API or -profiler-maxusedmemory command line parameter to increase maximum allowed memory usage.
Using 16793600 bytes while Profiler.maxUsedMemory is 16777216 bytes."
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