I was having a problem with a map I was building so I decided just to start over and see what happens.
I made a room about 1200X800x400 and built a building inside. Its a simple foursided building, two story, and has a row of windows that goes all the way around. A elevator in the center that is controled by func_train. The windows are all func_breakable with the window texture on them. They're covered with a hint brush to help with vvis. I have some props on each floor. The outside bo in covered with just a brick texture.
Ok, it seems like such a simple map. But my question is why does it take 4 hours to compile? Everything seems ok until it get to portalflow in the compile and it just sits there. I've made maps ten times the size and it takes twenty minutes to compile them.
I read the tutorial on optimizing a map. I'm making everything I can into a func-detail and using hint brushes where I can. But a simple map like this shouldn't take that long to compile.