Unreal Engine NOT using 100% of CPU to compile

Hi All,
When I open a project, the editor loads but it’s compiling 8000 shaders.
I have a 16 core /32 thread CPU, but my CPU is being used between 10% to 15%.
Sometimes I see my SSD go upto 100%, but regardless of SSD usage, CPU always sits around 10 to 15%.

Why is the editor not using 100% CPU power?
Is it something I need to fix with windows?

Hey @Virtual_Lens!

So one option you can do is increase the amount of usable threads for the “Shader Compile Worker” program that runs behind the scenes. That’s the program actually doing the work. To increase the amount of threads go to your Config/Base Engine.ini and change the line that says:

NumUnusedShaderCompilingThreads=x (X will be whatever the current amount is).

It’s a pretty safe setting to play with. Set that higher and watch it compile lickety split!

Thanks, I’ve done that now, but it’s still not working.
My CPU is just being used at less than 10%. I have no idea why it’s doing this?!

You can change the process priority in the task Manager

Or in the Engine installation directory: such as UE_5.0EA\ engine \Config\BaseEngine.ini,Ctrl + F search “WorkerProcessPriority”

Change -1 to 1, save and exit.

Just to confirm, none of this work. Installing a fresh OS did.

ShaderCompilerCoreCountThreshold