> 3x more hardware # for Postgres

Tells you something about how insanely costly Oracle's licenses are. Whatever you say about Oracle though - Oracle DB is an incredibly well performing and reliable piece of software. (Attested by experience - we had several Oracle DBs running on HP-UX Itanium that only needed to be handled when OS and Oracle patches were needed. Massively used too - think 36 PA-RISC cores at peak, 24 IA64 ones. It also helps that there are lot of DBAs with great deal of Oracle experience.)