Profiling and debugging a heavily modded Forge server

[Sivertsen]

Does there exist any easy way to profile and debug the performance of a Forge server running many mods? I've tried searching for something that does, but haven't found anything particular. I know Opis exists. But it doesn't give a full image of all that is going on. For instance I had a an overstuffed pipe on a server that completely lagged down everything and nothing came up with Opis. The problem I'm having now is that my server is grinding at a measly 3 ticks per second, and the client goes into an infinite loop as soon as I log in.

 

Since I haven't found what mods that are causing the issues I'm having, reporting to the modpack author isn't of much use. I could remove half of the mods at a time and check if it's still running like a turd in a binary like search. This is however rather tedious. Especially with the long start up times.

[luacs1998]

I've found that using java profilers, such as yourkit or jvisualvm, can see which mods are causing issues.