Hi.
Im using dedicated machine form hetzner.
AMD Ryzen™ 5 3600
CPU
6 cores / 12 threads @ 3.6 GHz
Generation:
Matisse (Zen 2)
RAM
64 GB DDR4 RAM
Drives
2 x 512 GB NVMe SSD
I had a lots modpack on this machine before and no one lag, even in the late game. We recently finish Ultimate Progresion. where we play with 8 players until end game. And server did't lag.
Yesterday we decide to change pack fo ATM7. I download and install pack as ussualy. Run it. And login on the server. And from the first minutes we got tps spikes. Whatever if there is one player or 7-8 server laging. In logs constantly we have msg that player move to quick. And server can't keep up. This is my java config :

-Xms2G
-Xmx16G
-XX:+UseG1GC
-XX:+ParallelRefProcEnabled
-XX:MaxGCPauseMillis=200
-XX:+UnlockExperimentalVMOptions
-XX:+DisableExplicitGC
-XX:+AlwaysPreTouch
-XX:G1NewSizePercent=30
-XX:G1MaxNewSizePercent=40
-XX:G1HeapRegionSize=8M
-XX:G1ReservePercent=20
-XX:G1HeapWastePercent=5
-XX:G1MixedGCCountTarget=4
-XX:InitiatingHeapOccupancyPercent=15
-XX:G1MixedGCLiveThresholdPercent=90
-XX:G1RSetUpdatingPauseTimePercent=5
-XX:SurvivorRatio=32
-XX:+PerfDisableSharedMem
-XX:MaxTenuringThreshold=1

I am having similar trouble. Admittedly without as much of the power of your specs but the server shouldn't be as laggy as it is, I feel like. I am runnign the server with -Xmx6G -Xms6G inside a docker container on a Debian VM on an ESXi server hosted at Hetzner. I found however that immediately after start htop shows 10GB RAM usage eventhough the server should be capped at 6.

Now, I don't know if that is caused by the modpack, the JVM or the container but it's quite frustrating to get ported back several hundred blocks every couple of minutes.

I would be more than happy to provide any debug data needed or investigate myself if given pointers on where to start!

I believe it might be an issue with BYG, because every time my server lags hard, the console spits out something like

7578 biome parameter points were mapped for BYG region: byg:region_0
7578 biome parameter points were mapped for BYG region: byg:region_1
7578 biome parameter points were mapped for BYG region: byg:region_2
7578 biome parameter points were mapped for BYG region: byg:region_3

And keeps looping, lagging the server really hard

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

I haven't noticed any change in that regard; my server is still lagging heavily.

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.