Re: Help: 8.0.3 Vacuum of an empty table never completes ... - Mailing list pgsql-hackers

James Robinson <jlrobins@socialserve.com> writes:
> As fate would have it, the vacuumdb frontend and backend which were  
> initially afflicted are still in existence:

OK, so pid 19244 isn't blocked on any lmgr lock; else we'd see an entry
with granted = f for it in pg_locks.  It could be blocked on a lower
level lock though.  Can you attach to that PID with gdb and get a stack
trace?  Something like (as postgres user)
gdb /path/to/postgres-executable 19244gdb> btgdb> quitok to detach? yes
        regards, tom lane