Package org.apache.solr.cluster.placement

Interface BalanceRequest

All Superinterfaces:

ModificationRequest

All Known Implementing Classes:

BalanceRequestImpl

public interface BalanceRequest
extends ModificationRequest

A cluster related placement request that Solr asks a PlacementPlugin to resolve and compute replica balancing plan for replicas that already exist across a set of Nodes.

The set of Nodes on which the replicas should be balanced across is specified (defaults to being equal to the set returned by Cluster.getLiveDataNodes()).

Method Summary

Modifier and Type	Method	Description
int	getMaximumBalanceSkew()
Set<Node>	getNodes()	Replicas should only be balanced on nodes in the set returned by this method.

Methods inherited from interface org.apache.solr.cluster.placement.ModificationRequest

getCollection

Method Detail

getNodes

Set<Node> getNodes()

Replicas should only be balanced on nodes in the set returned by this method.

When Collection API calls do not specify a specific set of nodes, replicas can be balanced on all live nodes in the cluster. In such cases, this set will be equal to the set of all live nodes. The plugin placement code does not need to worry (or care) if a set of nodes was explicitly specified or not.

Returns:

never null and never empty set (if that set was to be empty for any reason, no balance would be possible and the Solr infrastructure driving the plugin code would detect the error itself rather than calling the plugin).

getMaximumBalanceSkew

int getMaximumBalanceSkew()