@InterfaceAudience.Private public class FavoredStochasticBalancer extends StochasticLoadBalancer implements FavoredNodesPromoter
LoadBalancer
that assigns favored
nodes for each region. There is a Primary RegionServer that hosts the region, and then there is
Secondary and Tertiary RegionServers. Currently, the favored nodes information is used in
creating HDFS files - the Primary RegionServer passes the primary, secondary, tertiary node
addresses as hints to the DistributedFileSystem API for creating files on the filesystem. These
nodes are treated as hints by the HDFS to place the blocks of the file. This alleviates the
problem to do with reading from remote nodes (since we can make the Secondary RegionServer as the
new Primary RegionServer) after a region is recovered. This should help provide consistent read
latencies for the regions even when their primary region servers die. This provides two
CandidateGenerator
Modifier and Type | Class and Description |
---|---|
(package private) class |
FavoredStochasticBalancer.FavoredNodeLoadPicker |
private class |
FavoredStochasticBalancer.FavoredNodeLocalityPicker |
StochasticLoadBalancer.GeneratorType
Modifier and Type | Field and Description |
---|---|
private FavoredNodesManager |
fnm |
private static org.slf4j.Logger |
LOG |
candidateGenerators, COST_FUNCTIONS_COST_FUNCTIONS_KEY, DEFAULT_KEEP_REGION_LOADS, DEFAULT_MAX_RUNNING_TIME, DEFAULT_MAX_STEPS, DEFAULT_MIN_COST_NEED_BALANCE, DEFAULT_RUN_MAX_STEPS, DEFAULT_STEPS_PER_REGION, KEEP_REGION_LOADS, loads, MAX_RUNNING_TIME_KEY, MAX_STEPS_KEY, MIN_COST_NEED_BALANCE_KEY, namedQueueRecorder, OVERALL_COST_FUNCTION_NAME, RUN_MAX_STEPS_KEY, STEPS_PER_REGION_KEY
BALANCER_DECISION_BUFFER_ENABLED, BALANCER_REJECTION_BUFFER_ENABLED, clusterStatus, DEFAULT_BALANCER_DECISION_BUFFER_ENABLED, DEFAULT_BALANCER_REJECTION_BUFFER_ENABLED, DEFAULT_HBASE_MASTER_LOADBALANCE_BYTABLE, isByTable, masterServerName, metricsBalancer, MIN_SERVER_BALANCE, onlySystemTablesOnMaster, rackManager, regionFinder, services, slop, useRegionFinder
FAVORED_ALWAYS_ASSIGN_REGIONS
BOGUS_SERVER_NAME, SYSTEM_TABLES_ON_MASTER, TABLES_ON_MASTER
Constructor and Description |
---|
FavoredStochasticBalancer() |
Modifier and Type | Method and Description |
---|---|
private void |
addRegionToMap(Map<ServerName,List<RegionInfo>> assignmentMapForFavoredNodes,
RegionInfo region,
ServerName host) |
private void |
assignRegionToAvailableFavoredNode(Map<ServerName,List<RegionInfo>> assignmentMapForFavoredNodes,
RegionInfo region,
ServerName primaryHost,
ServerName secondaryHost,
ServerName tertiaryHost) |
protected List<RegionPlan> |
balanceTable(TableName tableName,
Map<ServerName,List<RegionInfo>> loadOfOneTable)
Given the cluster state this will try and approach an optimal balance.
|
protected List<CandidateGenerator> |
createCandidateGenerators() |
void |
generateFavoredNodesForDaughter(List<ServerName> servers,
RegionInfo parent,
RegionInfo regionA,
RegionInfo regionB) |
void |
generateFavoredNodesForMergedRegion(RegionInfo merged,
RegionInfo[] mergeParents) |
private Map<ServerName,List<RegionInfo>> |
generateFNForRegionsWithoutFN(FavoredNodeAssignmentHelper helper,
List<RegionInfo> regions) |
List<ServerName> |
getFavoredNodes(RegionInfo regionInfo) |
private Set<ServerName> |
getInheritedFNForDaughter(FavoredNodeAssignmentHelper helper,
List<ServerName> parentFavoredNodes,
FavoredNodesPlan.Position primary,
FavoredNodesPlan.Position secondary) |
private List<ServerName> |
getOnlineFavoredNodes(List<ServerName> onlineServers,
List<ServerName> serversWithoutStartCodes) |
protected CandidateGenerator |
getRandomGenerator()
Returns any candidate generator in random
|
private ServerName |
getServerFromFavoredNode(List<ServerName> servers,
ServerName fn) |
private void |
mergeAssignmentMaps(Map<ServerName,List<RegionInfo>> assignmentMap,
Map<ServerName,List<RegionInfo>> otherAssignments) |
ServerName |
randomAssignment(RegionInfo regionInfo,
List<ServerName> servers)
Used to assign a single region to a random server.
|
Map<ServerName,List<RegionInfo>> |
retainAssignment(Map<RegionInfo,ServerName> regions,
List<ServerName> servers)
Generates a bulk assignment startup plan, attempting to reuse the existing assignment
information from META, but adjusting for the specified list of available/online servers
available for assignment.
|
Map<ServerName,List<RegionInfo>> |
roundRobinAssignment(List<RegionInfo> regions,
List<ServerName> servers)
Generates a bulk assignment plan to be used on cluster startup using a simple round-robin
assignment.
|
private Pair<Map<ServerName,List<RegionInfo>>,List<RegionInfo>> |
segregateRegionsAndAssignRegionsWithFavoredNodes(Collection<RegionInfo> regions,
List<ServerName> onlineServers) |
void |
setMasterServices(MasterServices masterServices)
Set the master service.
|
private void |
updateFavoredNodesForRegion(RegionInfo regionInfo,
List<ServerName> newFavoredNodes) |
composeAttributeName, computeCost, getCandidateGenerators, getCostFunctionNames, initCosts, loadConf, needsBalance, nextAction, setRackManager, updateBalancerLoadInfo, updateClusterMetrics, updateCostsAndWeightsWithAction, updateMetricsSize
assignMasterSystemRegions, balanceCluster, balanceMasterRegions, getConf, getDefaultSlop, idleRegionServerExist, initialize, isStopped, onConfigurationChange, postMasterStartupInitialize, preBalanceCluster, regionOffline, regionOnline, shouldBeOnMaster, sloppyRegionServerExist, stop, toEnsumbleTableLoad, updateBalancerStatus
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
isMasterCanHostUserRegions, isSystemTablesOnlyOnMaster, isTablesOnMaster
private static final org.slf4j.Logger LOG
private FavoredNodesManager fnm
public FavoredStochasticBalancer()
protected List<CandidateGenerator> createCandidateGenerators()
createCandidateGenerators
in class StochasticLoadBalancer
protected CandidateGenerator getRandomGenerator()
getRandomGenerator
in class StochasticLoadBalancer
public void setMasterServices(MasterServices masterServices)
LoadBalancer
setMasterServices
in interface LoadBalancer
setMasterServices
in class BaseLoadBalancer
@NonNull public Map<ServerName,List<RegionInfo>> roundRobinAssignment(List<RegionInfo> regions, List<ServerName> servers) throws HBaseIOException
BaseLoadBalancer
roundRobinAssignment
in interface LoadBalancer
roundRobinAssignment
in class BaseLoadBalancer
regions
- all regionsservers
- all serversHBaseIOException
private void mergeAssignmentMaps(Map<ServerName,List<RegionInfo>> assignmentMap, Map<ServerName,List<RegionInfo>> otherAssignments)
private Map<ServerName,List<RegionInfo>> generateFNForRegionsWithoutFN(FavoredNodeAssignmentHelper helper, List<RegionInfo> regions) throws IOException
IOException
private Pair<Map<ServerName,List<RegionInfo>>,List<RegionInfo>> segregateRegionsAndAssignRegionsWithFavoredNodes(Collection<RegionInfo> regions, List<ServerName> onlineServers) throws HBaseIOException
HBaseIOException
private void addRegionToMap(Map<ServerName,List<RegionInfo>> assignmentMapForFavoredNodes, RegionInfo region, ServerName host)
private ServerName getServerFromFavoredNode(List<ServerName> servers, ServerName fn)
private void assignRegionToAvailableFavoredNode(Map<ServerName,List<RegionInfo>> assignmentMapForFavoredNodes, RegionInfo region, ServerName primaryHost, ServerName secondaryHost, ServerName tertiaryHost)
public ServerName randomAssignment(RegionInfo regionInfo, List<ServerName> servers) throws HBaseIOException
BaseLoadBalancer
randomAssignment
in interface LoadBalancer
randomAssignment
in class BaseLoadBalancer
regionInfo
- Region for which this selection is being done. nnHBaseIOException
private void updateFavoredNodesForRegion(RegionInfo regionInfo, List<ServerName> newFavoredNodes) throws IOException
IOException
@NonNull public Map<ServerName,List<RegionInfo>> retainAssignment(Map<RegionInfo,ServerName> regions, List<ServerName> servers) throws HBaseIOException
BaseLoadBalancer
Takes a map of all regions to their existing assignment from META. Also takes a list of online servers for regions to be assigned to. Attempts to retain all assignment, so in some instances initial assignment will not be completely balanced.
Any leftover regions without an existing server to be assigned to will be assigned randomly to available servers.
retainAssignment
in interface LoadBalancer
retainAssignment
in class BaseLoadBalancer
regions
- regions and existing assignment from metaservers
- available serversHBaseIOException
private List<ServerName> getOnlineFavoredNodes(List<ServerName> onlineServers, List<ServerName> serversWithoutStartCodes)
public List<ServerName> getFavoredNodes(RegionInfo regionInfo)
public void generateFavoredNodesForDaughter(List<ServerName> servers, RegionInfo parent, RegionInfo regionA, RegionInfo regionB) throws IOException
generateFavoredNodesForDaughter
in interface FavoredNodesPromoter
IOException
private Set<ServerName> getInheritedFNForDaughter(FavoredNodeAssignmentHelper helper, List<ServerName> parentFavoredNodes, FavoredNodesPlan.Position primary, FavoredNodesPlan.Position secondary) throws IOException
IOException
public void generateFavoredNodesForMergedRegion(RegionInfo merged, RegionInfo[] mergeParents) throws IOException
generateFavoredNodesForMergedRegion
in interface FavoredNodesPromoter
IOException
protected List<RegionPlan> balanceTable(TableName tableName, Map<ServerName,List<RegionInfo>> loadOfOneTable)
StochasticLoadBalancer
balanceTable
in class StochasticLoadBalancer
tableName
- the table to be balancedloadOfOneTable
- region load of servers for the specific one tableCopyright © 2007–2020 The Apache Software Foundation. All rights reserved.