Ue4 4.10.1 appears to have a memory leak related to the actor window that is running up 30GB’s of ram in about 3-4 hours. I can send my project privately upon request if an engineer wishes to take a look into the cause.
The bug report in the other AH thread turned out to be a duplicate of another bug report(UE-23820) which is fixed in 4.11 (Just tested it).
The reason it occurs is that you have a ton of tabs open at once, when the tabs are too small(before 4.11), it creates a memory leak. It has to do with how it handles the tab text. So the workaround is to keep your number of tabs to a minimum, especially if you don’t view the blueprints full screen.