Stream levels during Play in Editor

Hi,

my world is a big streamed open world city using world composition. When i package my game and start its working fine. The levels are streamed during runtime without any lags. When i start my game in the unreal editor first time it takes +5 minutes before the window game appears. When i start to move the game everytime starts to freeze and lagg when it starts to stream the parts of my city. This is very annoying when i need to test my game. I have already turned on under editor settings “Stream sub levels during play in editor” but its doesnt work. How i can force the editor to stream the sub levels during PIE from the disk (like in the packaged build) instead of duplicatem them into memory? (i think this is the reason why its so lagging) Please help

nobody can help me?