HG - why does it cause my system to become unresponsive

I am using HG, mercurial, to backup some binary and text files (about 12G worth). I am pushing to a remote repository and my system becomes unresponsive (the mouse and keyboard don't do anything).

The CPU is busy, but not flat-lined, also, I have about 1.5GB of free memory.

What is causing my system to choke? This is the first time I have ever pushed the contents to the repositor开发者_Go百科y, so there should be about 3.5GB of total data to transmit (how much space HG is using).

Try running Process Monitor to get a log of what HG is trying to do while your computer is hung.