Environment
Minecraft: 1.21.1
NeoForge: 21.1.225
Create Aeronautics: 1.2.1+mc1.21.1
Sable: 1.2.2
Dedicated Linux server
Problem description
We are experiencing severe server lag when using Honey Glue to create or modify contraptions in Create Aeronautics.
The issue starts immediately after Honey Glue is applied to connect blocks and the contraption is assembled or updated. Server TPS drops significantly and the console starts logging repeated UDP packet decode errors.
The issue is reproducible and appears to be directly related to glued contraption updates.
Observed behavior
Heavy server lag / TPS drops after using Honey Glue i.e. creating the contraption
Increased network packet processing
Repeated UDP decode failures in the server console
Contraption snapshot synchronization appears unstable
Console errors
Recurring errors:
Caused by: java.io.IOException: Received an invalid packet ID: 254
at dev.ryanhcode.sable.network.udp.SableUDPPacketDecoder.decode(...)
io.netty.handler.codec.DecoderException:
java.io.IOException: Received an invalid packet ID: 254
Failed to decode UDP packet of type SNAPSHOT
java.lang.IndexOutOfBoundsException:
readerIndex(30) + length(8) exceeds writerIndex(33)
What we tested
All players are using the exact same modpack versions
Client and server mod versions match
Turned off the UDP in the Sable config
Suspected cause
It seems that contraption snapshot synchronization in Sable’s UDP pipeline may produce malformed or incomplete packets when contraption structures are updated through Honey Glue.
Reproduction steps
Start a dedicated server
Join with a matching client modpack
Build a contraption
Use Honey Glue to connect blocks
Assemble or modify the contraption
Observe server lag and UDP decode errors in console
Additional notes
Environment
Minecraft: 1.21.1
NeoForge: 21.1.225
Create Aeronautics: 1.2.1+mc1.21.1
Sable: 1.2.2
Dedicated Linux server
Problem description
We are experiencing severe server lag when using Honey Glue to create or modify contraptions in Create Aeronautics.
The issue starts immediately after Honey Glue is applied to connect blocks and the contraption is assembled or updated. Server TPS drops significantly and the console starts logging repeated UDP packet decode errors.
The issue is reproducible and appears to be directly related to glued contraption updates.
Observed behavior
Heavy server lag / TPS drops after using Honey Glue i.e. creating the contraption
Increased network packet processing
Repeated UDP decode failures in the server console
Contraption snapshot synchronization appears unstable
Console errors
Recurring errors:
Caused by: java.io.IOException: Received an invalid packet ID: 254
at dev.ryanhcode.sable.network.udp.SableUDPPacketDecoder.decode(...)
io.netty.handler.codec.DecoderException:
java.io.IOException: Received an invalid packet ID: 254
Failed to decode UDP packet of type SNAPSHOT
java.lang.IndexOutOfBoundsException:
readerIndex(30) + length(8) exceeds writerIndex(33)
What we tested
All players are using the exact same modpack versions
Client and server mod versions match
Turned off the UDP in the Sable config
Suspected cause
It seems that contraption snapshot synchronization in Sable’s UDP pipeline may produce malformed or incomplete packets when contraption structures are updated through Honey Glue.
Reproduction steps
Start a dedicated server
Join with a matching client modpack
Build a contraption
Use Honey Glue to connect blocks
Assemble or modify the contraption
Observe server lag and UDP decode errors in console
Additional notes