By default, each server pool is configured with the following attribute options for managing server pools:
MIN_SIZE: The minimum number of servers the server pool should contain.
If the number of servers in a server pool is below the value of this attribute, then Oracle Clusterware automatically moves servers from elsewhere into the server pool until the number of servers reaches the attribute value.
MAX_SIZE: The maximum number of servers the server pool should contain.
IMPORTANCE: A number from 0 to 1000 (0 being least important) that ranks a server pool among all other server pools in a cluster.
In addition, you can assign additional attributes to provide more granular management of server pools, as part of a cluster configuration policy. Attributes such as EXCLUSIVE_POOLS and SERVER_CATEGORY can assist you to create policies for your server pools that enhance performance and build tuning design management into your server pool.