How to Configure the Control Domain

This procedure contains examples of resources to set for your control domain. These numbers are examples only, and the values used might not be appropriate for your control domain.

For domain sizing recommendations, see Oracle VM Server for SPARC Best Practices (http://www.oracle.com/technetwork/server-storage/vm/ovmsparc-best-practices-2334546.pdf).

Assign virtual CPUs to the control domain.
Service domains, including the control domain, require CPU and memory resources to perform virtual disk and virtual network I/O operations for guest domains. The amount of CPU and memory resources to allocate depends on the workload of the guest domain.

For example, the following command assigns two CPU cores (16 virtual CPU threads) to the control domain, primary. The remainder of the virtual CPU threads are available for guest domains.
```
primary# ldm set-core 2 primary
```
You can dynamically change the actual CPU allocation based on application requirements. Use the ldm list command to determine the CPU utilization of the control domain. If the control domain has high CPU utilization, use the ldm add-core and ldm set-core commands to add CPU resources to a service domain.
Assign memory to the control domain.
For example, the following command assigns 16 Gbytes of memory to the control domain, primary. This setup leaves the remainder of the memory available to guest domains.
```
primary# ldm set-memory 16G primary
```
Save the SP configuration to the service processor (SP).
For example, the following command would add an SP configuration called initial.
```
primary# ldm add-spconfig initial
```
Verify that the SP configuration is ready to be used at the next reboot.
```
primary# ldm list-spconfig
factory-default
initial [current]
```
This ldm list-spconfig command shows that the initial configuration set will be used after you perform a power cycle.
Reboot the control domain to make the reconfiguration changes take effect.