Resource Reconfiguration

A system that runs the Oracle VM Server for SPARC software is able to configure resources, such as virtual CPUs, virtual I/O devices, cryptographic units, and memory. Some resources can be configured dynamically on a running domain, while others must be configured on a stopped domain. If a resource cannot be dynamically configured on the control domain, you must first initiate a delayed reconfiguration. The delayed reconfiguration postpones the configuration activities until after the control domain has been rebooted.

Dynamic Reconfiguration

Dynamic reconfiguration (DR) enables resources to be added or removed while the operating system (OS) is running. The capability to perform DR of a particular resource type is dependent on having support in the OS running in the logical domain.

Dynamic reconfiguration is supported for the following resources:

• Virtual CPUs – Supported in all versions of the Oracle Solaris 10 OS

• Virtual I/O devices – Supported in at least the Solaris 10 10/08 OS

• Cryptographic units – Supported in at least the Oracle Solaris 10 9/10 OS

• Memory – Supported starting with the Oracle VM Server for SPARC 2.0 release (see Using Memory Dynamic Reconfiguration)

• Physical I/O devices – Not supported

To use the DR capability, the Logical Domains DR daemon, drd, must be running in the domain that you want to change. See the drd(1M) man page.

Delayed Reconfiguration

In contrast to DR operations that take place immediately, delayed reconfiguration operations take effect in the following circumstances:

• After the next reboot of the OS

• After a stop and start of a logical domain

Delayed reconfiguration operations are restricted to the control domain. For all other domains, you must stop the domain to modify the configuration unless the resource can be dynamically reconfigured.

When a delayed reconfiguration is in progress on the control domain, other reconfiguration requests for the control domain are deferred until it is rebooted, or stopped and started.

The ldm cancel-operation reconf command cancels delayed reconfiguration operations on the control domain. For more information about how to use the delayed reconfiguration feature, see the ldm(1M) man page.

You can use delayed reconfiguration to decrease resources on the control domain. To remove a large number of CPUs from the control domain, see Removing a Large Number of CPUs From the Control Domain in Oracle VM Server for SPARC 2.1 Release Notes. To remove large amounts of memory from the control domain, see Decrease the Control Domain's Memory.