Any chance you could push a new version for 1.8.9 to remove constant log spam of:

[06:46:49] [Client thread/INFO] [STDOUT/]: biomesoplenty.common.world.WorldChunkManagerBOP::67]: settings for world:
[06:46:49] [Client thread/INFO] [STDOUT/]: biomesoplenty.common.world.WorldChunkManagerBOP:initialLandAndSeaLayer:99]: Setting up andmass VANILLA

Thank you.

It certainly can be removed, although currently it should only appear once each time you load a world. Is this not the case?

No, it's appearing several times a second for as long as the world is loaded...

And it seems the pastebins I use all have a file size limit the log exceeds. Sorry about the zip :/
fml-client-latest.zip

That actually seems like a bug in another mod you have installed. Someone appears to be calling worldType.getWorldChunkManager(world) multiple times when they really really shouldn't be, causing countless instances to be unnecessarily constructed. I would suggest progressively removing mods until it no longer occurs.

Even if the log messages are disabled (which they shouldn't need to be), you'll still have a massive problem that likely has performance impacts happening behind the scenes, even with world types from Vanilla.

zazpro (BStuff) author says that he's not using getWorldChunkManager at all. Any idea what else could be causing the log spam when the two mods are together? Thanks.

BStuff Issue: http://minecraft.curseforge.com/projects/baubles-stuff/issues/11

I tracked it down to Baubles Stuff, though I'm not sure why a mod that does no worldgen needs to know about how the world is generated. Thank you for the pointer.

I'll take a look myself, but I suspect he's doing it indirectly if that's the case

Okay, the problem arises from md.zazpro.mod.common.baubles.Ring_Core in his clientTick method. Doing this in a tick method is a big no-no:

Wrapper.INSTANCE.world().provider.registerWorld(Wrapper.INSTANCE.world());

I can say with almost certainty that that would be the cause of it. Also that method calls getWorldChunkManager, which is why the multiple constructions occur.