UE4 is using 100% of CPU

Hi everyone!

I know this question were asked here few times, but I couldn’t find suitable answer.

UE4 is using 100% of CPU when I want to renew material image in viewport, while I work with shaders. Also the same thing is happening while UE4 compiling materials for landscape for example.

Is it problem with UE4, or is it my hardware?

My hardwar:
Intel Core i5-6600K CPU @ 3.50GHz (4 cores)
16 gb of RAM
NVIDIA GeForce GTX 1060

Thank you.

When you compile shaders the engine will launch “ShaderCompileWorker.exe” for each core you have on your system minus a defined number based on Install Path\Engine\Config\BaseEngine.ini
These are for unused so the smaller the number the more cores are used.

The multiple instances of the compiler and the UE4 Editor all demand CPU power and you can get up to 100% easily.

There are some more flags you can tweak for debugging but turning these to false and forgetting would be a bad idea.