Oracle licensing: What did your customers do?

You are talking about the soft partitioning vs hard partitioning licenses with Oracle. Soft partitioning doesn't allow a reduction in licenses here, all physical cpu cores on all physical servers must be licensed, whether used or not. It is possible to use hard partitioning as means to limit the number of software licenses required for any given server or a cluster of servers for the approved hard partitioning technologies like Solaris (PDOMS/containers/Zones), IBM LPAR, Oracle VM and Oracle Engineered systems.

So first thing you should do is verify whether your customer is using approved hard partitioning technology for license reduction.

These strategy were more relevant for the consolidation on the On-premise setup, they are not so relevant on the cloud. We usually recommend customers to decouple the Databases. In terms of real life stories we haven't seen any of the customers using EC2 Dedicated hosts (apart from vmWare on AWS).

So it is always choice between RDS or EC2 and we only recommend EC2 when some workload or features can't be fulfilled by Oracle RDS. We do have several instance type with varying level of CPU to memory ratio to help customers with the licensing. There are few other things coming up to help customers with these kind of use cases.