"Urciolo, Kevin" <Kevin.Urciolo@ngc.com> writes:
> I am having a problem where row exclusive locks are causing applications
> and vacuums to hang. I shutdown all applications, but the locks remain.
> I stop and start postgres, but the locks are still there. A pid is not
> listed. This problem started showing up after switching to the XA
> datasource with the Postgres JDBC driver. Is this causing problems?
The null PID fields indicate that these locks are being held by
uncommitted prepared transactions, so the pg_prepared_xacts view might
give you useful info. I concur that this suggests an XA problem.
You might have better luck asking about that in the pgsql-jdbc list.
regards, tom lane