CPU pools enable management of CPU resources on Oracle Database Appliance on both bare metal and KVM deployments. There are two types of CPU pools, that is, BM and VM.
• Creating a CPU Pool in a Bare Metal or KVM Deployment
Use ODACLI commands or the Browser User Interface to create a CPU pool in a bare metal or KVM deployment.
• Viewing CPU Pools in a Bare Metal or KVM Deployment
Use ODACLI commands or the Browser User Interface to view all CPU pools or details about a CPU pool in a bare metal or KVM deployment.
• Modifying a CPU Pool in a Bare Metal or KVM Deployment
Use ODACLI commands or the Browser User Interface to modify a CPU pool in a bare metal or KVM deployment.
• Deleting a CPU Pool in a Bare Metal or KVM Deployment
Use ODACLI commands or the Browser User Interface to delete a CPU pool in a bare metal or KVM deployment.
• Viewing CPU Pool Audit Records in a Bare Metal or KVM Deployment
Use ODACLI commands or the Browser User Interface to delete a CPU pool in a bare metal or KVM deployment.
• About Over-Subscribed CPU Pools
Configure virtual machines so that they do not subscribe to more CPU resources than the resources available in CPU pools.
About CPU Pools
CPU pools enable management of CPU resources on Oracle Database Appliance on both bare metal and KVM deployments. There are two types of CPU pools, that is, BM and VM.
Use the BM CPU pool to ensure that the database on a bare metal host runs
exclusively on the CPU lists specified in the CPU pool. All Oracle processes are bound to the CPUs in this CPU pool and run only on these CPUs. The bare metal CPU pool is assigned to database by updating the init.ora parameter processor_group_name.
Use the VM CPU pools to cage and manage CPU resource allocations to workloads for virtual machines. Workloads are isolated by creating CPU pools and assigning or
pinning virtual machines to a specific CPU pool. When you pin a virtual machine to a CPU pool, you ensure that the virtual machine uses CPUs in only that CPU pool. Resources in CPU pools cannot overlap, that is, CPU pools cannot share CPUs. But one CPU pool can be assigned to multiple databases (BM CPU pool) or VMs (VM CPU pools).
Oracle Database Appliance provides ODACLI commands to create, update, modify, and delete CPU pools.
About Bare Metal CPU Pools
For new databases, you can attach the new CPU pool using the create-database
command. For existing databases, use the modify-database command to attach the
CPU pool to the database. Restart the database manually for changes to take effect. Clone, irestore and recover database operations will also try to use the same CPU pool if the CPU pool is used by the source database. Specify the --cpupool option
to use the new cpupool. The standby database uses the CPU pool configured for the primary database. Specify the --cpupool option in the irestore-database command
when restoring the backup to the standby site if you want to use a separate CPU pool on the standby site. For more details about the command syntax, see the Oracle
Database Appliance Command Line Interface chapter in this guide.
About VM CPU Pools
For new VMs, you can attach the new CPU pool using the create-vm command. For
existing VMs, use the modify-vm command to attach or update the CPU pool. Use the --live option to apply the changes to a running VM, and use the --config parameter
to persist the change. For more details about the command syntax, see the Oracle
Database Appliance Command Line Interface chapter in this guide.
About Audit Records for CPU Pools
CPU pool operations history are recorded in audit records metadata and system log for audit purposes. The CPU pool changes include create, modify, delete operations, and attach and detach operations from VMs and databases. The CPU pool audit records can be queried using odacli list-auditrecords and odacli describe- auditrecord commands but they can not be changed or deleted. For more details
about the command syntax, see the Oracle Database Appliance Command Line
Interface chapter in this guide.
Understanding the Effect of Changing the CPU Cores on CPU Pool Allocation
You may have changed the CPU core count on Oracle Database Appliance using the
odacli update-cpucore command. You must assign cores in multiples of two, with a
minimum of two cores. If you change the CPU core count, then you can subsequently only increase the CPU core count.
If you change the CPU core count in an Oracle Database Appliance environment which has CPU pools, then the following behavior is seen:
• odacli create-cpupool and odacli modify-cpupool will always select the online
CPUs. Therefore, on both bare metal and KVM deployments, any CPU pool created after running the odacli update-cpucore command, will select from the
available online CPUs.
• For existing CPU pools on bare metal and KVM deployments, some CPUs can become offline when you run the odacli update-cpucore command. Check the
CPU pools for any offline CPUs using the odacli describe-cpupool command.
You can then update the CPU pool to use available ONLINE CPUs by using the
odacli modify-cpupool command.
• If the databases use a CPU pool and some CPUs become offline, then use the
odacli modify-cpupool command to update the CPU pool. Restart the databases
to use the updated CPU pool.