BaseLoadBalancer.Cluster (Apache HBase 1.2.12 API)

java.lang.Object
- org.apache.hadoop.hbase.master.balancer.BaseLoadBalancer.Cluster

Enclosing class:

BaseLoadBalancer
```
protected static class BaseLoadBalancer.Cluster
extends Object
```
An efficient array based implementation similar to ClusterState for keeping the status of the cluster in terms of region assignment and distribution. LoadBalancers, such as StochasticLoadBalancer uses this Cluster object because of hundreds of thousands of hashmap manipulations are very costly, which is why this class uses mostly indexes and arrays. Cluster tracks a list of unassigned regions, region assignments, and the server topology in terms of server names, hostnames and racks.

Nested Class Summary

Nested Classes
Modifier and Type	Class and Description
`static class`	`BaseLoadBalancer.Cluster.Action` An action to move or swap a region
`static class`	`BaseLoadBalancer.Cluster.AssignRegionAction`
`static class`	`BaseLoadBalancer.Cluster.MoveRegionAction`
`static class`	`BaseLoadBalancer.Cluster.SwapRegionsAction`

Field Summary

Fields
Modifier and Type	Field and Description
`(package private) Map<ServerName,List<HRegionInfo>>`	`clusterState`
`(package private) boolean`	`hasRegionReplicas`
`(package private) String[]`	`hosts`
`(package private) Map<String,Integer>`	`hostsToIndex`
`(package private) int[]`	`initialRegionIndexToServerIndex`
`private Comparator<Integer>`	`localityComparator`
`(package private) float[]`	`localityPerServer`
`(package private) boolean`	`multiServersPerHost`
`static BaseLoadBalancer.Cluster.Action`	`NullAction`
`(package private) int`	`numHosts`
`(package private) int[]`	`numMaxRegionsPerTable`
`(package private) int`	`numMovedRegions`
`(package private) int`	`numRacks`
`(package private) int`	`numRegions`
`private Comparator<Integer>`	`numRegionsComparator`
`(package private) int[][]`	`numRegionsPerServerPerTable`
`(package private) int`	`numServers`
`(package private) int`	`numTables`
`(package private) int[][]`	`primariesOfRegionsPerHost`
`(package private) int[][]`	`primariesOfRegionsPerRack`
`(package private) int[][]`	`primariesOfRegionsPerServer`
`protected RackManager`	`rackManager`
`(package private) String[]`	`racks`
`(package private) Map<String,Integer>`	`racksToIndex`
`private RegionLocationFinder`	`regionFinder`
`(package private) int[]`	`regionIndexToPrimaryIndex`
`(package private) int[]`	`regionIndexToServerIndex`
`(package private) int[]`	`regionIndexToTableIndex`
`(package private) Deque<RegionLoad>[]`	`regionLoads`
`(package private) int[][]`	`regionLocations`
`(package private) HRegionInfo[]`	`regions`
`(package private) int[][]`	`regionsPerHost`
`(package private) int[][]`	`regionsPerRack`
`(package private) int[][]`	`regionsPerServer`
`(package private) Map<HRegionInfo,Integer>`	`regionsToIndex`
`(package private) int[]`	`serverIndexToHostIndex`
`(package private) int[]`	`serverIndexToRackIndex`
`(package private) Integer[]`	`serverIndicesSortedByLocality`
`(package private) Integer[]`	`serverIndicesSortedByRegionCount`
`(package private) ServerName[]`	`servers`
`(package private) int[][]`	`serversPerHost`
`(package private) int[][]`	`serversPerRack`
`(package private) Map<String,Integer>`	`serversToIndex`
`(package private) ArrayList<String>`	`tables`
`(package private) Map<String,Integer>`	`tablesToIndex`

Constructor Summary

Constructors
Modifier	Constructor and Description
`protected`	`BaseLoadBalancer.Cluster(Collection<HRegionInfo> unassignedRegions, Map<ServerName,List<HRegionInfo>> clusterState, Map<String,Deque<RegionLoad>> loads, RegionLocationFinder regionFinder, RackManager rackManager)`
`protected`	`BaseLoadBalancer.Cluster(Map<ServerName,List<HRegionInfo>> clusterState, Map<String,Deque<RegionLoad>> loads, RegionLocationFinder regionFinder, RackManager rackManager)`

Method Summary

Methods
Modifier and Type	Method and Description
`(package private) int[]`	`addRegion(int[] regions, int regionIndex)`
`(package private) int[]`	`addRegionSorted(int[] regions, int regionIndex)`
`(package private) void`	`calculateRegionServerLocalities()`
`(package private) boolean`	`contains(int[] arr, int val)`
`void`	`doAction(BaseLoadBalancer.Cluster.Action action)`
`(package private) void`	`doAssignRegion(HRegionInfo regionInfo, ServerName serverName)`
`(package private) int`	`getLeastLoadedTopServerForRegion(int region)`
`(package private) float`	`getLocality(int server)`
`(package private) float`	`getLocalityOfRegion(int region, int server)`
`(package private) int`	`getLowestLocalityRegionOnServer(int serverIndex)`
`(package private) int`	`getLowestLocalityRegionServer()`
`(package private) int`	`getNumRegions(int server)`
`(package private) void`	`regionMoved(int region, int oldServer, int newServer)`
`private void`	`registerRegion(HRegionInfo region, int regionIndex, int serverIndex, Map<String,Deque<RegionLoad>> loads, RegionLocationFinder regionFinder)` Helper for Cluster constructor to handle a region
`(package private) int[]`	`removeRegion(int[] regions, int regionIndex)`
`(package private) int[]`	`replaceRegion(int[] regions, int regionIndex, int newRegionIndex)`
`(package private) void`	`sortServersByLocality()`
`(package private) void`	`sortServersByRegionCount()`
`String`	`toString()`
`(package private) boolean`	`wouldLowerAvailability(HRegionInfo regionInfo, ServerName serverName)` Return true if the placement of region on server would lower the availability of the region in question

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Detail

servers
```
ServerName[] servers
```

hosts
```
String[] hosts
```

racks
```
String[] racks
```

multiServersPerHost
```
boolean multiServersPerHost
```

tables
```
ArrayList<String> tables
```

regions
```
HRegionInfo[] regions
```

regionLoads
```
Deque<RegionLoad>[] regionLoads
```

regionFinder

private RegionLocationFinder regionFinder

regionLocations
```
int[][] regionLocations
```

serverIndexToHostIndex
```
int[] serverIndexToHostIndex
```

serverIndexToRackIndex
```
int[] serverIndexToRackIndex
```

regionsPerServer
```
int[][] regionsPerServer
```

regionsPerHost
```
int[][] regionsPerHost
```

regionsPerRack
```
int[][] regionsPerRack
```

primariesOfRegionsPerServer
```
int[][] primariesOfRegionsPerServer
```

primariesOfRegionsPerHost
```
int[][] primariesOfRegionsPerHost
```

primariesOfRegionsPerRack
```
int[][] primariesOfRegionsPerRack
```

serversPerHost
```
int[][] serversPerHost
```

serversPerRack
```
int[][] serversPerRack
```

regionIndexToServerIndex
```
int[] regionIndexToServerIndex
```

initialRegionIndexToServerIndex
```
int[] initialRegionIndexToServerIndex
```

regionIndexToTableIndex
```
int[] regionIndexToTableIndex
```

numRegionsPerServerPerTable
```
int[][] numRegionsPerServerPerTable
```

numMaxRegionsPerTable
```
int[] numMaxRegionsPerTable
```

regionIndexToPrimaryIndex
```
int[] regionIndexToPrimaryIndex
```

hasRegionReplicas
```
boolean hasRegionReplicas
```

serverIndicesSortedByRegionCount

Integer[] serverIndicesSortedByRegionCount

serverIndicesSortedByLocality
```
Integer[] serverIndicesSortedByLocality
```

serversToIndex
```
Map<String,Integer> serversToIndex
```

hostsToIndex
```
Map<String,Integer> hostsToIndex
```

racksToIndex
```
Map<String,Integer> racksToIndex
```

tablesToIndex
```
Map<String,Integer> tablesToIndex
```

regionsToIndex
```
Map<HRegionInfo,Integer> regionsToIndex
```

localityPerServer
```
float[] localityPerServer
```

numServers
```
int numServers
```

numHosts
```
int numHosts
```

numRacks
```
int numRacks
```

numTables
```
int numTables
```

numRegions
```
int numRegions
```

numMovedRegions
```
int numMovedRegions
```

clusterState

Map<ServerName,List<HRegionInfo>> clusterState

rackManager

protected final RackManager rackManager

NullAction

public static final BaseLoadBalancer.Cluster.Action NullAction

numRegionsComparator

private Comparator<Integer> numRegionsComparator

localityComparator

private Comparator<Integer> localityComparator

Constructor Detail

BaseLoadBalancer.Cluster

protected BaseLoadBalancer.Cluster(Map<ServerName,List<HRegionInfo>> clusterState,
                        Map<String,Deque<RegionLoad>> loads,
                        RegionLocationFinder regionFinder,
                        RackManager rackManager)

BaseLoadBalancer.Cluster

protected BaseLoadBalancer.Cluster(Collection<HRegionInfo> unassignedRegions,
                        Map<ServerName,List<HRegionInfo>> clusterState,
                        Map<String,Deque<RegionLoad>> loads,
                        RegionLocationFinder regionFinder,
                        RackManager rackManager)

Method Detail

registerRegion

private void registerRegion(HRegionInfo region,
                  int regionIndex,
                  int serverIndex,
                  Map<String,Deque<RegionLoad>> loads,
                  RegionLocationFinder regionFinder)

Helper for Cluster constructor to handle a region

doAction

public void doAction(BaseLoadBalancer.Cluster.Action action)

wouldLowerAvailability
```
boolean wouldLowerAvailability(HRegionInfo regionInfo,
                             ServerName serverName)
```
Return true if the placement of region on server would lower the availability of the region in question

Parameters:
server -
region -

Returns:
true or false

doAssignRegion

void doAssignRegion(HRegionInfo regionInfo,
                  ServerName serverName)

regionMoved

void regionMoved(int region,
               int oldServer,
               int newServer)

removeRegion

int[] removeRegion(int[] regions,
                 int regionIndex)

addRegion

int[] addRegion(int[] regions,
              int regionIndex)

addRegionSorted

int[] addRegionSorted(int[] regions,
                    int regionIndex)

replaceRegion

int[] replaceRegion(int[] regions,
                  int regionIndex,
                  int newRegionIndex)

sortServersByRegionCount
```
void sortServersByRegionCount()
```

getNumRegions
```
int getNumRegions(int server)
```

contains

boolean contains(int[] arr,
               int val)

sortServersByLocality
```
void sortServersByLocality()
```

getLocality
```
float getLocality(int server)
```

getLowestLocalityRegionServer
```
int getLowestLocalityRegionServer()
```

getLowestLocalityRegionOnServer

int getLowestLocalityRegionOnServer(int serverIndex)

getLocalityOfRegion

float getLocalityOfRegion(int region,
                        int server)

getLeastLoadedTopServerForRegion

int getLeastLoadedTopServerForRegion(int region)

calculateRegionServerLocalities
```
void calculateRegionServerLocalities()
```

toString
```
public String toString()
```
Overrides:

toString in class Object

Class BaseLoadBalancer.Cluster

Nested Class Summary

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

servers

hosts

racks

multiServersPerHost

tables

regions

regionLoads

regionFinder

regionLocations

serverIndexToHostIndex

serverIndexToRackIndex

regionsPerServer

regionsPerHost

regionsPerRack

primariesOfRegionsPerServer

primariesOfRegionsPerHost

primariesOfRegionsPerRack

serversPerHost

serversPerRack

regionIndexToServerIndex

initialRegionIndexToServerIndex

regionIndexToTableIndex

numRegionsPerServerPerTable

numMaxRegionsPerTable

regionIndexToPrimaryIndex

hasRegionReplicas

serverIndicesSortedByRegionCount

serverIndicesSortedByLocality

serversToIndex

hostsToIndex

racksToIndex

tablesToIndex

regionsToIndex

localityPerServer

numServers

numHosts

numRacks

numTables

numRegions

numMovedRegions

clusterState

rackManager

NullAction

numRegionsComparator

localityComparator

Constructor Detail

BaseLoadBalancer.Cluster

BaseLoadBalancer.Cluster

Method Detail

registerRegion

doAction

wouldLowerAvailability

doAssignRegion

regionMoved

removeRegion

addRegion

addRegionSorted

replaceRegion

sortServersByRegionCount

getNumRegions

contains

sortServersByLocality

getLocality

getLowestLocalityRegionServer

getLowestLocalityRegionOnServer

getLocalityOfRegion

getLeastLoadedTopServerForRegion

calculateRegionServerLocalities

toString