StreamingEnabled: destroyed welds failing to replicate

Bug Reports Engine Bugs
#1

Reproduction Steps
Starting yesterday, my tree cutting system began to fail. The trees are made of parts and welds, and are created and manipulated entirely on the server. I have not updated the game in several weeks. Private repro file attached.

Occurs both in live servers and in studio on Win10.

Expected Behavior
When you cut a tree down, it falls down. The weld that connects the tree to its former stump is destroyed on the server and this replicates to the clients.

Actual Behavior
When you chop a tree, the tree falls correctly on the server but on the client it appears frozen in place.

You can use Settings/Physics/Are Assemblies Shown to see that the assembly is correctly broken on the server, but on the client there the whole tree is incorrectly still a single assembly.

In the explorer, you can see that there is a weld in the part “b1_1” which was destroyed on the server, but this was not replicated to the client and it still exists for the client. If you locally destroy the weld and then try to push around the new assembly, the assembly will resync after a few seconds.

Client view:

2560Ă—1417 268 KB

Server view:

2560Ă—1417 265 KB

Workaround
If you turn off StreamingEnabled, the welds replicate as expected.

Issue Area: Engine
Issue Type: Other
Impact: High
Frequency: Constantly
Date First Experienced: 2022-03-29 20:03:00 (-04:00)
A private message is associated with this bug report

12 Likes
StreamingEnabled: Constant Crashing
#2

Thanks for the bug report, we are investigating.

4 Likes
#3

Around the same time, a building tool in my game stopped replicating parts immediately.
Similarly, turning off StreamingEnabled fixes the issue.

1 Like
#4

Unsure if directly related, but having this enabled was causing my servers to crash every 30-2h. Since I had disabled it, I no longer have this issue.

1 Like
#5

Something similar happened to us

Our NPCs existed on the server, but they didnt on the client, so it looked like you were getting attacked out of nowhere XD

2 Likes
#6

What is the place id you were seeing crashes on, and when was this happening?

#7

Any chance you can share a repro place with us?

#8

This began happening frequently about 2 weeks ago, where the servers would begin crashing at a pace of 2 hours/server. This is when I decreased my server sizes to 150 players.

Once I did that, they began crashing at a rate of 30 minutes/server.

I’ve kept it disabled for ~5 days, and it no longer replicates, however it frustrates my community on lower-end devices and mobile, as it is no longer possible for them to connect, and they face crashes due to the big size of our game.

I used StreamingEnabled to well optimize this issue, however due to these issues, it causes my servers to crash at a rapid rate, so I had to resort to disabling it until it was fixed.

#9

I don’t see any server crashes for 7287725541 in the last 30 days. It looks like there were some crashes back in February, but the were all due to out of memory. If there are issues with your game related to streaming enabled, it doesn’t seem to be due to welds failing to replicate, which is the subject of this thread. Can you create a separate bug report if you believe there are issues with streaming enabled and your game?