org.apache.druid.server.coordinator.rules

Class LoadRule

java.lang.Object

org.apache.druid.server.coordinator.rules.LoadRule

All Implemented Interfaces:

Rule

Direct Known Subclasses:

ForeverLoadRule, IntervalLoadRule, PeriodLoadRule

public abstract class LoadRule
extends Object
implements Rule

LoadRules indicate the number of replicants a segment should have in a given tier.

Field Summary

Fields

Modifier and Type	Field and Description
String	NON_PRIMARY_ASSIGNED_COUNT
static String	REQUIRED_CAPACITY

Constructor Summary

Constructors

Constructor and Description
LoadRule()

Method Summary

Modifier and Type	Method and Description
boolean	canLoadSegments() Return true if this Rule can load segment onto one or more type of Druid node, otherwise return false.
abstract int	getNumReplicants(String tier)
abstract Map<String,Integer>	getTieredReplicants()
CoordinatorStats	run(DruidCoordinator coordinator, DruidCoordinatorRuntimeParams params, DataSegment segment) DruidCoordinatorRuntimeParams.getUsedSegments() must not be called in Rule's code, because the used segments are not specified for the DruidCoordinatorRuntimeParams passed into Rule's code.
void	updateUnderReplicated(Map<String,it.unimi.dsi.fastutil.objects.Object2LongMap<String>> underReplicatedPerTier, SegmentReplicantLookup segmentReplicantLookup, DataSegment segment) This method should update the with the replication count of the .
void	updateUnderReplicatedWithClusterView(Map<String,it.unimi.dsi.fastutil.objects.Object2LongMap<String>> underReplicatedPerTier, SegmentReplicantLookup segmentReplicantLookup, DruidCluster cluster, DataSegment segment) This method should update the with the replication count of the taking into consideration the number of servers available in cluster that the segment can be replicated on.
protected static void	validateTieredReplicants(Map<String,Integer> tieredReplicants)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface org.apache.druid.server.coordinator.rules.Rule

appliesTo, appliesTo, getType

Field Detail

NON_PRIMARY_ASSIGNED_COUNT

public final String NON_PRIMARY_ASSIGNED_COUNT

See Also:

Constant Field Values

REQUIRED_CAPACITY

public static final String REQUIRED_CAPACITY

See Also:

Constant Field Values

Constructor Detail

LoadRule

public LoadRule()

Method Detail

run

public CoordinatorStats run(DruidCoordinator coordinator,
                            DruidCoordinatorRuntimeParams params,
                            DataSegment segment)

Description copied from interface: Rule

DruidCoordinatorRuntimeParams.getUsedSegments() must not be called in Rule's code, because the used segments are not specified for the DruidCoordinatorRuntimeParams passed into Rule's code. This is because DruidCoordinatorRuntimeParams entangles two slightly different (nonexistent yet) abstractions: "CoordinatorDutyParams" and "RuleParams" which contain params that only CoordinatorDuty objects and Rules need, respectively. For example, ReplicationThrottler needs to belong only to "RuleParams", but not to "CoordinatorDutyParams". The opposite for the collection of used segments and DataSourcesSnapshot. See https://github.com/apache/druid/issues/7228

Specified by:

run in interface Rule

canLoadSegments

public boolean canLoadSegments()

Description copied from interface: Rule

Return true if this Rule can load segment onto one or more type of Druid node, otherwise return false. Any Rule that returns true for this method should implement logic for calculating segment under replicated in Rule.updateUnderReplicated(java.util.Map<java.lang.String, it.unimi.dsi.fastutil.objects.Object2LongMap<java.lang.String>>, org.apache.druid.server.coordinator.SegmentReplicantLookup, org.apache.druid.timeline.DataSegment)

Specified by:

canLoadSegments in interface Rule

updateUnderReplicated

public void updateUnderReplicated(Map<String,it.unimi.dsi.fastutil.objects.Object2LongMap<String>> underReplicatedPerTier,
                                  SegmentReplicantLookup segmentReplicantLookup,
                                  DataSegment segment)

Description copied from interface: Rule

This method should update the with the replication count of the . Rule that returns true for Rule.canLoadSegments() must override this method. Note that is a map of tier -> { dataSource -> underReplicationCount }

Specified by:

updateUnderReplicated in interface Rule

updateUnderReplicatedWithClusterView

public void updateUnderReplicatedWithClusterView(Map<String,it.unimi.dsi.fastutil.objects.Object2LongMap<String>> underReplicatedPerTier,
                                                 SegmentReplicantLookup segmentReplicantLookup,
                                                 DruidCluster cluster,
                                                 DataSegment segment)

Description copied from interface: Rule

This method should update the with the replication count of the taking into consideration the number of servers available in cluster that the segment can be replicated on. Rule that returns true for Rule.canLoadSegments() must override this method. Note that is a map of tier -> { dataSource -> underReplicationCount }

Specified by:

updateUnderReplicatedWithClusterView in interface Rule

validateTieredReplicants

protected static void validateTieredReplicants(Map<String,Integer> tieredReplicants)

getTieredReplicants

public abstract Map<String,Integer> getTieredReplicants()

getNumReplicants

public abstract int getNumReplicants(String tier)