Using CPU dynamic reconfiguration (DR) to power down virtual CPUs does not work with processor sets, resource pools, or the zone's dedicated CPU feature.
When using CPU power management in elastic mode, the Solaris OS guest sees only the CPUs that are allocated to the domains that are powered on. That means that output from the psrinfo(1M) command dynamically changes depending on the number of CPUs currently power-managed. This causes an issue with processor sets and pools, which require actual CPU IDs to be static to allow allocation to their sets. This can also impact the zone's dedicated CPU feature.
Workaround: Set the performance mode for the power management policy.