High lag when playing with network emulation and on LAN?

Whenever I test my game in PIE, on LAN, on one machine, using “average” network emulation, there appears to be a high amount—much higher than what should be “average”—of lag, rubber-banding, and stuttering when it comes to movement, gameplay abilities, etc. When I play the same way with a packaged build (no network emulation), there’s still lag, but I don’t know if it has something to do with the fact that one of the clients is always in the background/out of focus, and thus has a lower frame-rate.

This is the kind of lag I am talking about. The first clip is in PIE, with two clients and a dedicated server. The second clip is a listen server in the left window and a client in the right window.

I haven’t changed any of Unreal’s built-in movement, and I’m confident I’ve set up the Gameplay Ability System correctly. Is there something I did wrong, or something I forgot to do/configure?

Does anyone know what could be causing this problem, or if it’s even a problem at all?

PIE Client mode starts a server in the background and everything is run under “one process”. This is more performant than a server, and 2 client instances. Disable that and you’ll see what I mean.

The hardware you’re running on is also a huge factor. Servers (listen server hosts) need a lot of CPU and RAM.

Question I have is why are you running network emulation on a packaged build that’s networked over LAN?

Disabling “one process” unfortunately does not improve the network lag.

Question I have is why are you running network emulation on a packaged build that’s networked over LAN?

I was only running network emulation when playing on one machine in PIE. I wasn’t using network emulation in the packaged build.

The way it reads seemed as you where. All good.

Is the LAN wifi or ethernet?

I’m using WiFi, but it’s decently quick. I rarely surpass 10-15ms of latency in online games.