Hello everyone. I am running a forge modded server server on my computer with 2 GB of ram allocated (I have tried with 4 and it did not help). I connect to my server via localhost and everything is fine until my Brother joins on his laptop. When he joins using my local IP 192.168.0.7 the server's tps just goes way down near 5-10 and the world gets laggy. lag between block breaks, when he walks he teleports all over. This is my start.bat java -Xms2048m -Xmx2048m -Xmn512m -XX:TargetSurvivorRatio=80 -XX:MaxTenuringThreshold=15 -XX:+UseParNewGC -XX:+UseConcMarkSweepGC -XX:+DisableExplicitGC -XX:MaxGCPauseMillis=40 -XX:GCPauseIntervalMillis=150 -XX:+AggressiveOpts -XX:PermSize=1024m -XX:+TieredCompilation -XX:ReservedCodeCacheSize=2048m -XX:+UseCodeCacheFlushing -XX:CompileThreshold=1000 -jar forge-1.7.10-10.13.4.1614-1.7.10-universal.jar nogui I am running a 1.7.10 Forge Server (forge 1.7.10-10.13.4.16.14-1.7.10-universal.jar to be exact) I have the following mods server+client side: https://imgur.com/a/YyTqPFT (obviously do not have optifine, mousetweaks and other client mods on the server side) I have tried installing Sampler to determine what was causing the issue and it said something about Chunk Update: Grass Tick Also almost constantly when we are both connected my console is always outputting this: [07:31:51] [Server thread/WARN]: Can't keep up! Did the system time change, or is the server overloaded? Running 2037ms behind, skipping 40 tick(s) The running behind delay is anywhere from 50ms to 5000ms. Not sure what is causing the low tps when he joins since it is only locally hosted. I have tried to include as much information as I knew about this problem. If you need any more information please ask. Also i'm sorry if this doesn't belong here.