[BUG] High CPU Usage First Launch and Later

My system is giving me high CPU warnings with Rocket, well before the app is even bootstrapped.

On first run, after all materials have been processed, and I’m presented with the New Project dialog… my system is sitting at a solid 80-90% CPU usage across all four cores.

Later after naming my project and opening the editor, I see the “Compiling Shaders” notification. Is UE4 per chance compiling shaders in the background while the New Project dialog is open as well? The notification is informative but you don’t see it until later if that’s the case.

After shader compilation is complete, I sit at about 60% CPU usage across all cores when the editor is idle and I have the default geometry (empty project) loaded.

We’re seeing the same kind of numbers here. So we’ve gone ahead and entered this issue into our database for investigation.

We’ve shipped Rocket with pre-compiled shaders, so you should never see that message more than a couple seconds. The fact that you’re compiling shaders explains the high CPU usage. I tested your installer and was unable to reproduce this. Did you by chance move/rename the Rocket install directory?

Looks like you also encountered a similar problem after your project was renamed. This broke the reference to your DDC (shader cache), so it attempted to recompile your shaders. This is a known issue that we’re looking into. Thanks for your feedback!

Sounds good. Though I’m still seeing ~40% CPU across all cores when my editor is just sitting idle and I have no meaningful project loaded.

Perhaps I have a borderline system requirements wise, but I seem to meet what is documented in the welcome PDF.

AMD Athlon II X4 630 2.8Ghz 64-Bit
6.0 GB RAM
Windows 7
GeForce GTS 250

AMD Athlon II X4 CPUs look to be 4 core. Using benchmark numbers, this definitely passes min spec but seems to be a bit slower than our targeted performance for recommended spec.

For comparison - what’s your CPU usage for a larger map such as ExampleMap? The default entry map should definitely be less taxing on your system. If not, looks like we need to do some investigating.

So with the “ExampleMap” of Example Game loaded, I’m seeing my overall CPU on all four cores level at about 65% (contrast that with the 40% of default project).

I have another PC that is 8 core and there I’m seeing about 45% across 6 of my 8 cores with ExampleMap, and a solid 30% or so with the default project.

Either way seems excessive since I’m doing nothing in the editor at the time, and I’m not in play mode or simulate mode (just an idle editor).

There is no change in CPU usage when the editor is minimized either. You’d imagine it would be straight forward to at least reduce CPU usage to 0 when minimized?