I have configured our user profile imports to pull from two AD
security groups. That worked well and the number of user profiles
generated is as expected. However, the Profile and Import settings
page indicates that the Profile Import status is Idle (took over 6
hours to do a full import of approx 600 users!) but the "Membership &
BDC import status" shows as Importing with over 5,000 records. We
don't have any BDC connection set up for anything, nevermind user
profile imports. We just have the one connection to AD. Can anyone
explain what is happening here? I've made more configuration tweaks
and need to kick off another full import, but can't because
SharePoint thinks its in the middle of an import already.

Perhaps not coincidentally, our search is stuck searching as well.
Search databases (DB log files and shared services search DB mdf) are
HUGE even though this is a dev environment where we have very little
content and nothing fancy configured. Databases keep maxing out the
space/memory.

Yes, we need to clean all this up and fix this environment, but I'm
wondering if anyone can shed light on what we should be looking for.