[Solved] Video Playback Lagging with AMD EGPU
Basically the title, 4k video, especially in full-screen is borderline unplayable. I've tested w/ VLC and it stutters pretty bad, and in YouTube basically any kind of video is unplayable in full-screen or larger windowed mode. The YouTube UI is also very laggy when in full-screen, if that helps. Not sure what's going on, if anyone has any ideas please let me know!
Here's some system info:
Kernel: 5.4.0-48 generic (although I did try 5.40-2x without success)
GPU: Radeon VII
More info is needed if you want help fixing this. For example, are you using an external display connected to the eGPU and if you are, are you using any of the scripts from this forum or any other method of setting the eGPU as the primary display?
In previous versions of LM + firefox youtube would be laggy in fullscreen mode and I had to opt into Webrender and hardware compositing using flags in about:config. But since the latest update Mint 20 base and firefox 80+ I think this is on by default so there shouldn't be any need to do that.
Might as well mention checking to make sure the package: mint-meta-codecs is installed and updated
Keep in mind that video codec matters. Only H.264 and H.265 are hardware accelerated on AMD Vega and earlier. So videos from youtube that mostly stream in VP9 are expected to use the CPU to decode.
Edit: The flags I set in firefox about:config are:
gfx.webrender.all = TRUE
gfx.webrender.compositor = TRUE