> I know that someone was working on a commercial extension to PostgreSQL
> to add clustering based on a shared disk system. Basically he was added a
> raw storage manager to PostgreSQL plus a lock manager to co-oridinate
> access to the shared disk. That way the two nodes could co-ordinate
> access to the shared disk. This is very similar to Oracle Parallel
Server.
This is sad. Good Cluster DB design is based on shared nothing architecture
and "function shipping". OPS is known to have a bad and antiquated
architecture
that only works well with extremely well thought out application design.
Andreas