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#28: Oracle Linux KVM is now accepted as Hard Partitioning technology
When aiming to limit the number of Oracle Processor licenses required, always take notice of Oracle’s Partitioning Policy. The content however, should remain considered “for educational purposes only”.
The Partitioning Policy is still a non-contractual document, that only provides guidelines regarding Oracle's “policies”. What do these guidelines include?
Partitioning, a recap
Partitioning occurs when CPU’s on a server are separated into individual sections, where each section acts as a separate system. Several virtualisation technologies are available for partitioning purposes.
- Hard Partitioning: Oracle-approved hard partitioning technologies as listed in the policy document are permitted as a means to limit the number of software licenses required for any given server or a cluster of servers;
- Soft Partitioning: Any technology not listed in the Hard Partitioning list, is considered soft partitioning. The use of vSphere (VMWare) is considered as Soft partitioning technologies. This results in a licensing need of all Hosts in the applicable Cluster/vCenter(s), depending on the Esxi-version used;
- Oracle Trusted Partitions: For approved Oracle Engineered Systems, Oracle permits the use of Oracle VM Server (OVM);
- Capacity on Demand: “Pay as You Grow” models. Oracle allows customers to license only the number of cores that are activated when the server is shipped.
So far for the items that contribute to a possible limitation on your use rights. It is probably a matter of time before Oracle decides its Partitioning Policy is outdated, should be adjusted and added to new contracts to be a real contractual binding.
The change: Oracle Linux KVM is now accepted as a Hard Partitioning technology
In the meanwhile, however, a small step was made, resulting into the following addition: Hard partitioning with Oracle Linux KVM in conjunction with Oracle Linux Virtualization Manager is now accepted by Oracle, when used in accordance with Oracle’s hard partition licensing requirements.
In this case, one must bind a virtual machine to physical CPUs or cores, preventing the software to run on other physical cores than the ones specified. Dedicated CPU resources are used by a VM instead of using all available CPUs of the server.
Even though this technology is accepted, some requirements and configurations are applicable:
- On a x86-based system, a CPU core (no hyperthreading enabled) or a CPU thread (hyperthreading enabled) within a core is presented as a physical CPU by the hypervisor;
- vCPUs (virtual CPUs) are exposed to the guest virtual machine as CPUs: the guest schedules applications on these vCPUs, and the hypervisor schedules these vCPU’s over the physical CPU cores or threads. All vCPUs from a guest are symmetrical. Oracle Linux KVM treats these equally, as long as scheduling parameters such as using CPU pinning have not changed;
- Oracle Linux KVM offers an advanced feature for hard partitioning, also known as CPU pinning. Hard partitioning means binding vCPUs to physical CPU threads or cores, and preventing these vCPUs from being scheduled on physical CPUs - threads or cores other than the ones specified;
- Live migration of CPU pinned virtual machines to another Oracle Linux KVM node is not permitted. Consequently, the cluster containing a pool of Oracle Linux KVM nodes with shared storage must not be configured with any scheduling policy available on Oracle Linux Virtualization Manager;
- When live migration is used with pinned virtual machines running Oracle software in an Oracle Linux KVM cluster, hard partition licensing for Oracle software is not applicable. You must determine the number of virtual machines running the Oracle software and then license the same number of physical servers (starting with the largest servers based on the CPU core count) up to the total number of the physical servers in the cluster;
- Live migration of other virtual machines with non-Oracle software within the server pool is not relevant to Oracle software hard partitioning or has no licensing impact;
- “Trusted Partitions” allow subset licensing without limitation on live migration, but only available on the approved Oracle Engineered Systems listed on Oracle licensing policies for partitioned environments.