Update: Notch has increased the amount of memory allocated to Minecraft when you start the game up using the .exe launcher. Following my advice below is no longer necessary.
I'm not much of a gamer, but I have been intrigued by Minecraft since seeing some of it's videos online. I promptly purchased the game to see what it is like. Unfortunately, after a while it started to crash within 5-10 minutes of starting the game up, and the screen would just go black.
Being that Minecraft is written in Java, and I work for Oracle in the Java organisation, I thought I'd see if I could improve it. After observing the memory usage (which you can see in game by holding F3), it seemed like there just wasn't enough memory being allocated to minecraft. To fix this you need to create a batch file (i.e. create a text document, and rename it to end in .bat), and put the following text inside it.
@echo off cd %AppData%\.minecraft start javaw -Xms1024m -Xmx1024m -Djava.library.path=".\bin\natives" -classpath "bin\minecraft.jar;bin\jinput.jar;bin\lwjgl.jar;bin\lwjgl_util.jar" net.minecraft.client.Minecraft
This batch file basically tells Minecraft to use more memory than what it is given by default. On my machine, this really helps to prevent the crashing, and also has the nice side-effect of improving performance due to minimising the need for frequent garbage collection. I have only tested this on my Windows 7 machine, so your mileage may vary - let me know how it works for you. This is definitely a Windows-only fix, although it's trivial for someone to create a shell script for Mac OS and Linux based on the above.