What happend with NavMesh baking in 5.5? Unbelievably slow!

I can't really understand... Looks like nobody has any problems with it...

I rebake my scene every now and then after I change stuff. It would take max 60 seconds to bake my whole scenes navmesh... (0.2 voxel size)

I upgraded to Unity 5.5 a few days ago and today I had to rebake my navmesh. It's ridiculously slow! I am already baking for 2 hours now and "Exporting Tiles" is around 40% at the moment. My Unity's version is 5.5.0f3 and I have a i7 6700k cpu with 16GB RAM and a geforce 1070...

Does anyone know what is going on?

 

I also noticed I cant move static objects in my scene anymore....?! They all have a "Combined Mesh (root: scene)" mesh on it. I never combined anything?! Maybe thats the cause? Is this something new?

 

I think there is a problem with "Combined Mesh (root: scene)" or something. I've got some objects with that component on it and they show up in my navmesh when they are not even navmesh static. But it gets ever more weird. They show up even after I've deleted them from the scene. So it seems unity is caching that mesh data somewhere? I think your mesh baking takes so long because unity is baking every single object that has the "Combined Mesh (root: scene)" component on it even though the objects are no nav meshes .

It seem that when one item is a nav mesh inside of the Combined Mesh it will use all mesh as a nav mesh. You could replace the Combined Mesh filter with the normal one. If you double click on the Combined mesh in the mesh filter you can see what's combined in that particular mesh filter.

 

i noticed that too, exporting tiles takes forever and it wasn't like this before.