Intel Xeon Phi Coprocessor 7120A for Build Lightmass?

I don’t think it can, for the price of that though you could buy a computer that’s more powerful with more memory.

The limitation for large levels is the amount of memory you have. But, if things are really big, then you might consider not using lightmaps at all, since even if you get them rendered it would take up a lot of hard drive space. That’s why open world games use dynamic lighting.