CPU/GPU Usage expectations (60-90%?)

Development Platform & Builds
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Hi, there. On builds using the shipping setting in Unreal 5.1, windows 10, I am seeing my game using around 60% of the CPU in menus and 90% of the GPU during play, while frames only take around 10ms to render.

This seems odd to me. I’ve tried to be performance conscious, not using high-res or high-poly assets, turning off ray tracing/lumen, scalability, etc… This is also a tiny project, relatively, with just a single level. Looking at stats inside the editor, I’m only seeing one number spiking there: RHIT (I don’t know what this is and googling failed, maybe someone can help there, too).

For reference, I looked at usage for a few other games on my machine, and they seem lower: Ring of Pain, which was something like 10-20% of CPU/GPU, and Sea of Thieves, which hovered around 40-50% of both and I think is made with Unreal 4.

Could I be accidentally not building for shipping properly (I think I’ve set it right, but could be wrong). Should I not be concerned about this? Is my game just using up CPU/GPU because it’s available or something? Other ideas? I’m not very knowledgeable about the performance side of things, but I would like to learn.

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The engine will use what resources are available to improve the experience.

You may be getting a higher frame rate, or the graphics driver may be spinning in a busy-wait loop waiting for the frame refresh which might count as “using the GPU” in windows instrumentation.

To figure out what it is, there are various modes you can change – draw everything with a simple shader, or draw everything with a small texture, or use a small window (320x240) and so on.

If one particular thing changes the amount of CPU used, you know that that’s the reason (e g, resolution → fill rate on the card.) If nothing changes the usage much, then it’s likely something more system-dependent, like the graphics drivers themselves.

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