Massive memory leak in Blueprint Editor introduced with Unreal 4.9

[Skifree]

@Syed;639598

My guess is as most others are not experiencing memory leak, it could be the certain bps or meshes in your level that are causing that. One way is elimination strategy (which may seem quite tiresome but with a bit of luck, doable in one day) - ie first try find the smallest level that can cause the memory leak. Then, start by removing half of the unique meshes. Save the level and reload the project. Do the usual stuffs and see if the memory leak is still there. If it is still leaking, remove again the half of the just halved-level, and redo the test.

Another way is to try to launch the editor from VC++, do the usual stuff and wait for it to crash. As usual, as it is run from VC++ it doesnt crash and just quit. If fact it will stop the VC++ and jump right into debugging mode and show you the exact location which causes the crash. Try to find something meaningful from there - watch the variables and see if they point to an object in the level. Check the callstack too.

Thirdly, create a new level just for repro case for Epic staff to look into. The level has to be as small as possible, and when the symptom appears upload the level into AnswerHub.

I haven’t tried reproduction in a blank project but my active project actually only consists of about 20 actors, simply hexagonal meshes with 8 faces.the rest of the level is just the normal defaults. At runtime, all classes are scooped up into class arrays and the actors are removed from the level, then everything is loaded into place via configuration - so the level itself in the editor has almost nothing in it.

I’ll have to test it out on a blank project to see if I can reproduce it.