Extreme Server Lag in Nether Only

Server Discussion
1

Hey, looking for some assistance with a Pixelmon SpongeForge server. My server runs at 20TPS consistently in all dimensions except for the Nether, which runs at approximately 8TPS. I’m trying to diagnose the issue so the game can be more playable for people, myself included. I’m relatively new to Sponge so if there’s any other information you need, I can supply it. Below are the timings I was asked to generate by the Pixelmon Generations devs; they told me it’s worldgen lag, but I wanted a second opinion because this lag happens no matter what. I have been AFK in the Nether for 20 minutes now and the TPS has not stabilized, which tells me it can’t be worldgen, unless I’m missing something.

Before Restart: Aikar's Timings Viewer
Most Recent: Aikar's Timings Viewer

2

Your lag is clearly caused by “Pixelmon::PixelmonSpawner_tickEnd (SELF)”. You have to ask Pixelmon devs what is it exactly but according to the name I doubt it is worldgen.

3

Yeah, that’s what I figured. I’m not sure what exactly it is either but I’m gonna do some troubleshooting tomorrow to see if I can figure out what causes it, since this only happens on the server and only in the Nether.

4

If anyone else has this issue with Pixelmon, hopefully this helps; in my case, it was the maximumPlants setting inside of the pixelmon.hocon file. Having that set to a large number (in my case, 512) was somehow the source of Nether lag.