FMemoryWriter , lighting, and huge maps

So I made this huge map, packaged it out and gave to my friends and we played without any problems. So then I went and built the lighting then I tried to package up the map to give to my friends and I get the, FMemoryWriter does not support data larger than 2GB. I searched all over the forums and the solution is to stream my map, but streaming maps does not support multiplayer. So I have been trouble shooting this problem and I have noticed that when Im packing the map I basically run out of RAM. I have a total of 24 GB and once I go over 22 GB bam I get the FMemory error. So now Im thinking the FMemory error is caused by running out of RAM. If so the only real way to fox this would be either shrink the map or get more RAM. Can any one confirm this? Thanks

If I make a map 4033x4033, then build the lighting, then package project it, all goes well.
If I make a map 8129x8129 , then build the lighting, then package project , the UE4 engine crashes with the error FMemoryWriter does not support data larger than 2GB.
If I dont build the lighting on the 8K map you can play on map and everything works fine. I can even package project and it works just fine.
So why is this happening? Why do I get FMemoryWriter does not support data larger than 2GB only after I build the lighting?

So if I put a check mark in the box next to Force No Precomputed Lighting in the world settings under lightmaps it fixes everything. Just what all this effects is unknown for me at this time.

Thank Hitpawz, he is the one who figured it out :slight_smile: Im really surprised no one here knew that.