Pushing a 2 MB commit fails with Write failed: Connection reset by peer

I'm trying to push a 2 MB commit to a private repo. that I've been using for a few weeks. All attempts to push have failed with:

Write failed: Connection reset by peer
fatal: The remote end hung up unexpectedly
fatal: The remote end hung up unexpectedly

The compression step is slower than I've ever seen it too.

I've never seen anything like this with git. Do I need to do some repo cleanup or optimization?

I'm using git 1.7.9 on cygwin64 on Windows 7 enterprise.