In Minecraft 1.11.2 with Forge, I see these errors in the log
[12:13:37] [Server thread/WARN] [FML]: Roguelike Dungeons loaded a new chunk (0, 43 Dimension: 0) during chunk population, causing cascading worldgen lag. Please report this to the mod's issue tracker. This log can be disabled in the Forge config.

mezz fixed a similar issue in Actually Additions with Ellpeck/ActuallyAdditions#690 , if that helps.

Mods:

• forge-1.11.2-13.20.0.2284
• Roguelike Dungeons 1.11.2-1.6.6

I just submitted several other bug reports from different mods including Embers, Inventory Pets, AbyssalCraft, Recurrent Complex, Astral Sorcery, denseores, and Roguelike Dungeons with this same log spam.

forge-1.11.2-13.20.0.2282
Roguelike Dungeons 1.11.2-1.6.6

[15:11:16] [Server thread/WARN]: Roguelike Dungeons loaded a new chunk (10, 13 Dimension: 0) during chunk population, causing cascading worldgen lag. Please report this to the mod's issue tracker. This log can be disabled in the Forge config.

capnkirok of Inventory-Pets seems to have the solution as well:

capnkirok/Inventory-Pets#170

Additional information regarding offsetting the structure "decoration" to help limit the number of extra chunks loading: https://www.reddit.com/r/feedthebeast/comments/5x0twz/investigating_extreme_worldgen_lag/

I think we can all appreciate that it's not this bad: http://i.imgur.com/SH3yRGa.png
We can additionally appreciate that that was fixed and now looks like: http://i.imgur.com/eynzCVR.png

That's a crazy amount of improvement. I had a rouge-like structure generate 31 chunks, which is luckily nowhere near that first example, still just a little high. (That being said that first example had several mods that were feeding into each other) The lower the extra chunks the less likely multiple mods are going to run away with each other and get married in Vegas estranging themselves from the family.