The current engine version (4.22) seems to suffer a huge performance hit when using the demo recording (demorec) feature. This issue is present in both the editor and the packaged game (developer builds). This is a regression from 4.21.2 (CL-4753647) where there was no change in FPS. From a Blank project the FPS drops from 120 to 30. In a Third Person project it drops from 120 to 15.

This was reported and tested in 4.22.2 (CL-6574378) and reproduced in 4.23 (CL-6810573)

Steps to Reproduce

1. Open the UE4 Editor and create a Blank or Third Person Template project
2. Close the project. In it's Config/DefaultEngine.ini add the following lines and then reopen the project:


3. Play in Ediotr and use "demorec" from the console. Observe the FPS. Then demostop

Results: There is a significant difference in performance (FPS) while recording a demo

Expected: No fps drop when recording a demo

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ComponentNetworking - Replay
Affects Versions4.234.22.2
Target Fix4.23
Fix Commit6849388
Main Commit6849388
CreatedJun 3, 2019
ResolvedJun 5, 2019
UpdatedJun 18, 2019