I think its a temporary fix for now. We’ve started receiving the following in the log when streaming a level:
[2017.11.24-10.49.15:367][836]LogStreaming: Error: Couldn't find file for package /Script/FunctionalTesting requested by async loading code. NameToLoad: /Script/FunctionalTesting
[2017.11.24-10.49.15:368][836]LogStreaming: Error: This will hitch streaming because it ends up searching the disk instead of finding the file in the pak file.
[2017.11.24-10.49.15:369][836]LogStreaming: Error: Found 1 dependent packages...
[2017.11.24-10.49.15:369][836]LogStreaming: Error: /Game/Maps/Build/IntroLevels/Sector4/CubePlacementPart3
We’ve never had this error before, although everything still loads, there is a minor hitch when streaming this particular level in a packaged game. Other than that, this fix seems to have improved level transition loading performance and overall game performance, infact our game has never performed as well due to this hack, bar the above hitch.