Earlier generations of virtualized environments could take 10 - 20% overhead versus a physical server. Today virtualized environments are taking 5 - 10% overhead while providing all the benefits and cost savings of a virtualized environment. Hardware and VMs are getting faster with every release. CPU vendors are now customizing their products for virtualization.
Virtualized Environments can run Faster than Physical Environments
There are also now a number of cases where a virtualized environment runs faster than a physical environment. Virtualized environments offer a number of advantages not available when running a traditional physical server. I am now running into customers that are virtualizing their application servers and database servers and seeing tremendous advantages over physical (non-virtualized) environments.
Oracle Does Provide Support for Databases Running on VMware
Oracle does provide support for Oracle database servers running virtualized. It makes sense because the Operating System and the Oracle Database Server do not realize they are running in a virtual machine, so there is no reason for virtualized environment to create a bug for Oracle. In fact, there are no Oracle bugs in the Oracle Metalink that are tied to the VMware ESX/ESXi virtualized environments. A few points that some customers do not understand:
- Oracle does provide support on VMware for bugs already known to Oracle.
- Oracle can support bugs on VMware if those bugs are not identified as being caused by virtualization software.
- Oracle does not support Oracle RAC in a VMware virtual environment but they do not prevent you from doing this. A number of customers are moving forward due to the tremendous advantages of running virtualized databases.
- Oracle may require the environment be recreated on a physical server if they believe it is due to a virtualization error.