Make sure you aren’t trying to track too many changes with the NetBeans mercurial plugin:
NetBeans memory - change how you start
Posted on August 14, 2007
If you’re running daily builds, and you’re seeing hangs in NetBeans Ruby, try launching with more memory:
nbrubyide_w.exe -J-Xmx256m --fontsize 12
It’s made a difference for me - haven’t seen a hang since I started doing this.