Package org.apache.hadoop.hbase.master.balancer

Interface Summary

Interface	Description
MetricsBalancerSource
MetricsStochasticBalancerSource	This interface extends the basic metrics balancer source to add a function to report metrics that related to stochastic load balancer.

Class Summary

Class	Description
AssignRegionAction
BalanceAction	An action to move or swap a region
BalancerChore	Chore that will call HMaster.balanceHMaster.balance() when needed.
BalancerClusterState	An efficient array based implementation similar to ClusterState for keeping the status of the cluster in terms of region assignment and distribution.
BalancerClusterState.DefaultRackManager
BalancerRegionLoad	Wrapper class for the few fields required by the StochasticLoadBalancer from the full RegionMetrics.
BaseLoadBalancer	The base class for load balancers.
CandidateGenerator	Generates a candidate action to be applied to the cluster for cost function search
ClusterLoadState	Class used to hold the current state of the cluster and how balanced it is.
ClusterStatusChore	Chore that will feed the balancer the cluster status.
CostFromRegionLoadAsRateFunction	Class to be used for the subset of RegionLoad costs that should be treated as rates.
CostFromRegionLoadFunction	Base class the allows writing costs functions from rolling average of some number from RegionLoad.
CostFunction	Base class of StochasticLoadBalancer's Cost Functions.
DoubleArrayCost	A helper class to compute a scaled cost using org.apache.commons.math3.stat.descriptive.DescriptiveStatistics#DescriptiveStatistics().
FavoredStochasticBalancer	An implementation of the LoadBalancer that assigns favored nodes for each region.
HeterogeneousRegionCountCostFunction	This is an optional Cost function designed to allow region count skew across RegionServers.
LoadBalancerFactory	The class that creates a load balancer from a conf.
LoadCandidateGenerator
LocalityBasedCandidateGenerator
LocalityBasedCostFunction	Compute a cost of a potential cluster configuration based upon where HStoreFiles are located.
MaintenanceLoadBalancer	a balancer which is only used in maintenance mode.
MemStoreSizeCostFunction	Compute the cost of total memstore size.
MetricsBalancer	Faced for exposing metrics about the balancer.
MetricsBalancerSourceImpl
MetricsStochasticBalancer	This metrics balancer uses extended source for stochastic load balancer to report its related metrics to JMX.
MetricsStochasticBalancerSourceImpl
MoveCostFunction	Given the starting state of the regions and a potential ending state compute cost based upon the number of regions that have moved.
MoveRegionAction
PrimaryRegionCountSkewCostFunction	Compute the cost of a potential cluster state from skew in number of primary regions on a cluster.
RackLocalityCostFunction
RandomCandidateGenerator
ReadRequestCostFunction	Compute the cost of total number of read requests The more unbalanced the higher the computed cost will be.
RegionCountSkewCostFunction	Compute the cost of a potential cluster state from skew in number of regions on a cluster.
RegionInfoComparator	The following comparator assumes that RegionId from HRegionInfo can represent the age of the region - larger RegionId means the region is younger.
RegionLocationFinder	This will find where data for a region is located in HDFS.
RegionReplicaCandidateGenerator	Generates candidates which moves the replicas out of the region server for co-hosted region replicas
RegionReplicaGroupingCostFunction	A cost function for region replicas.
RegionReplicaHostCostFunction	A cost function for region replicas.
RegionReplicaRackCandidateGenerator	Generates candidates which moves the replicas out of the rack for co-hosted region replicas in the same rack
RegionReplicaRackCostFunction	A cost function for region replicas for the rack distribution.
ServerAndLoad	Data structure that holds servername and 'load'.
ServerLocalityCostFunction
SimpleLoadBalancer	Makes decisions about the placement and movement of Regions across RegionServers.
SimpleLoadBalancer.BalanceInfo	Stores additional per-server information about the regions added/removed during the run of the balancing algorithm.
StochasticLoadBalancer	This is a best effort load balancer.
StoreFileCostFunction	Compute the cost of total open storefiles size.
SwapRegionsAction
TableSkewCostFunction	Compute the cost of a potential cluster configuration based upon how evenly distributed tables are.
WriteRequestCostFunction	Compute the cost of total number of write requests.

Enum Summary

Enum	Description
BalanceAction.Type
BalancerClusterState.LocalityType
StochasticLoadBalancer.GeneratorType