Reproduced in the launcher and github builds of version 4.14.3
Steps to reproduce:
Create a new project (Blank C++ project was used in this case)
Open Project Settings, leave it open
Open any blueprint (in this case \MyProject\Content\StarterContent\Blueprints\Blueprint_Effect_Explosion.uasset was used)
This freeze was also observed sometimes using Editor Settings instead of Project Settings. The engine appears to be infinitely looping inside FBlueprintEditor::CreateDefaultCommands(), inside one of the …Commands::Register() calls.
It does indeed continue to allocate memory (a few megabytes per second) during the freeze. Left alone long enough it eventually crashes the editor.
I have attached a DxDiag from this machine. I have confirmed this bug on one other machine (running a different project), but I won’t be able to get a DxDiag from it until Monday at least.
Test this again in a clean project following your steps, but before you start the test, navigate to Editor Preferences and search All Settings for Show Frame Rate and Memory and enable that.
After you’ve enabled this option, then test it again and track your memory using the in-editor display (it will show up on the top-right edge of the window, near the Close, Minimize, and Expand options).
Once you’ve done this, let me know a few things: what your memory usage starts at, what rate (approximately) you’re seeing it increase at, and what usage it reaches just before it crashes.
Also, document how long this process takes as well.
After opening the clean project and setting FR&Memory to show, it was showing 1,285.05mb and 39,793 objs. Shortly after opening the Blueprint (again, \MyProject\Content\StarterContent\Blueprints\Blueprint_Effect_Explosion.uasset) it jumped to 1,302.84mb and then stopped updating because the editor was frozen.
Task Manager and Resource Monitor started by showing the UnrealEditor process at 1,103.6mb and after opening the blueprint memory footprint increased at a rate of about 2.5mb/sec. About two minutes after opening the blueprint it showed 1,805mb, at three minutes about 2,024mb.
Interestingly it leveled off at about 2,545mb after about seven minutes. Approximately fifteen minutes after opening the blueprint, it actually opened and the editor unfroze. The FR&Memory readout in the editor showing 2,755.83mb and 62,113 objs.
I wasn’t watching it the whole time, but also of note, a few minutes after opening the Blueprint, the thread count for the UnrealEditor process in Resource Monitor was about 7,000, after opening the blueprint it was at about 10,000.
Thank you for performing those tests and logging the results. From what you’re describing, I’m not seeing anything abnormal. It’s not unusual for the editor to use upwards of even 8-10 gb of RAM depending on the project’s complexity.
I’m not sure why you’re experiencing a freeze at the usage levels you’re seeing; however.
Are your graphics card drivers fully up-to-date? If not, go ahead and update to the latest and then test it again. It’s possible that this could be responsible for the freeze as well.
Is this also occurring with a blank actor blueprint, by the way? I noticed you were using an asset from the starter content so I’d like to see what behavior you see with something much more simple.
Updated nVidia drivers to 378.49. Created a new code project with no starter content, created an Actor blueprint and later a Widget blueprint, both exhibited the above behavior. ~15 minute freeze, steady climb in memory usage and thread count up to about 2.2 gb and 10,000 threads.
I did notice however, that opening one of the blueprints before opening project settings prevented the freeze, even if that blueprint was later closed and re-opened while project settings remained open
As a result of you not experiencing this bug in 4.15 P2, I’m going to mark this topic as resolved. I imagine there was an undocumented fix put in for this as I could not find a ticket for it in our database.
Let me know if the issue pops back up in the future.