"Jason Palmer" <jpalmer@dlife.com> writes:
> ...  What we experience is bizarre.  We can always
> create tables with no sequences.  But occasionally the database will hang
> when we attempt to create a table with a sequence or foreign key.
Yup, that's pretty bizarre.  Is the backend consuming CPU (or I/O) in
this state, or is it just waiting?  If the latter, it's presumably
blocked on some lock, and you need to find out what.  First try looking
in pg_locks to see if it's blocked on a user-level lock.  If you don't
see anything there, then it's blocked on some internal lock (LWLock or
spinlock) --- you'll need to attach to the backend process with gdb and
get a stack trace to get some clue what's up.
            regards, tom lane