Minecraft Forums

So, I started MC up again after a long time without playing and decided to continue building an old map of mine. I have a VERY large black box made of black wool and I'm putting glowstone and lanterns into the ceiling to create a starry effect. However, every time I try to place a block, it takes approximately 10-20 seconds to actually place. The game freezes until it's done, almost as if the game crashed and windows "start looking for the problem" kind of freeze. This problem isn't present anywhere else on the map, just the ceiling and walls of this structure. Is this a computer problem, or an MC issue? Can I fix this or will I just have to deal with it? Any and all help is appreciated! Thanks!