Google Desktop Search size

I flattened my desktop machine last week, reinstalling all the software again. Google Desktop Search spent the weekend reindexing. Today I arrive at work and see:

Google Desktop Search has reached its maximum size. New items will no longer be indexed. You can still search for old items.

Searching with google found only one bit of info, on webjunkies.  It's fine info, but I'm stuck on editing a QWORD in the registry.  What's the byte order?

Looks like I'll have to write a small app...