0% GPU Usage on iMac 2019 with Radeon Pro 560x, help!

Solution 1:

It's not an issue.

You're not seeing any GPU usage because you're not using any GPU. Rendering static pages doesn't require any significant resources. Once it does render it, since it's technically not doing anything, there's no more reason for the GPU to be utilized.

Using a GPU Benchmark tool, Unigene's Heaven, I ran a process that specifically calls the GPU. This is continually rendering a high resolution animation. As you can see from Activity monitor, the GPU is being utilized.

You can also do this with a simple video; localally via QuickTime, VLC, or Elmedia and even through a web browser like a YouTube video. Below is Activity Monitor with a YouTube video playing in a Firefox tab and again we can see GPU utilization

Solution 2:

It may well be a software bug that Activity Monitor and other tools don't report any GPU usage. Alternatively, exactly what GPU% is measuring may be not what we think. Obviously, the GPU is doing something. You may get additional information in Activity Monitor > Window > GPU History.

My 2014 MBP with an integrated graphics unit also reports 0% GPU on every process. I can just get WindowServer to report 5% by scrolling a window like mad for several seconds.

From the spec, your 2019 has only the discrete Radeon GPU (since it doesn't need to fall back to a lower-power integrated unit like a laptop). So it has to be using the GPU if you're seeing stuff on the screen.

If you're not seeing any actual problems with the display, or performance issues with 'heavy' graphics tasks, then I'd say there's nothing to worry about.

Bear in mind that a lot of common tasks are actually trivial for modern hardware these days.

"Looking at data on what the OS is doing always leads to worry about whether it's the right numbers." ;-)