When the server restarts and there is a chunkloaded filler that isn't finished yet, it causes massive lag. The TPS drop to 3-4 (i used 3 fillers , each ~50x50x20, at once) until i remove the filler. Before the server restart there is no lag at all.

WAILA?

yes, WAILA is present. But it's not necessary to look at it, open its GUI or even be near it and there are no problems before the restart. but going to test without waila now

I know. Still. We've had six lag issues caused by WAILA at this point.

@m31t: ping?

ping is normal. removed WAILA. Still the same issues when using 4 Fillers
or more at once. All chunks loaded and no player online. cofh tps in
console shows bad values for overworld. But this only happens when you
restart the server after setting up the fillers.

but i have more mods running on that server. I will test this with only buildcraft (and something to load the chunks) and report back

@m31t: ping?

totally forgot about this. i used the wrong github account. :x Without WAILA i have no issues with normal sized fillers.

But there is definitly a problem with fillers exceeding the landmarks max_size of 64x64x64 (even without waila). For example if you use markerplus or any other IAreaProvider to mark for example a 256x100x256 area. Even if all chunks are loaded, the tps on the server drop to 10-15 and the server sometimes crashes. But with 16 single 64x100x64 fillers you don't have that problem.
I don't know if it's possible to avoid this with the way the filler works currently.
One solution may be to limit the max size of a filler and/or include a advanced filler that doesn't use "throwing blocks" and just fills all air blocks in the area without any exception and doesn't search spots it has placed something before again for a free spot.

Actually, the lag seems to come from sloppy coding in the blueprint system. What crashes are these? Can you provide a profiler log?

No unfortunately not. It's a while ago and currently i dont have time for minecraft because of exams.
Maybe it has to do something with storing and loading the progress of the filler from/to the world save?

@m31t - Does it still happen in BC 6.4.0?

@asiekierka cannot reproduce anymore with 6.4.0