Package org.apache.druid.server.coordinator.loading

Enum SegmentAction

java.lang.Object
java.lang.Enum<SegmentAction>
org.apache.druid.server.coordinator.loading.SegmentAction
All Implemented Interfaces:
Serializable, Comparable<SegmentAction>
public enum SegmentAction extends Enum<SegmentAction>
Represents actions that can be performed on a server for a single segment.

The different action types can be used to prioritize items in a LoadQueuePeon.

  • Enum Constant Details

    • DROP

      public static final SegmentAction DROP
      Drop a segment from a server.

    • LOAD

      public static final SegmentAction LOAD
      Load a segment on a server. This should be used when trying to load a segment on a tier where it is currently unavailable (i.e. no replicas loaded). This action cannot be throttled by the replicationThrottleLimit.

    • REPLICATE

      public static final SegmentAction REPLICATE
      Load a replica of a segment on a server. This should be used when trying to load more replicas of a segment on a tier where it is already available (i.e. atleast one loaded replica).

      This is different from LOAD in two ways:

      • this action can be throttled by the replicationThrottleLimit
      • it is given lower priority than LOAD on the load queue peon
      For all other purposes, REPLICATE is treated the same as LOAD.

    • MOVE_TO

      public static final SegmentAction MOVE_TO
      Move a segment to this server.

    • MOVE_FROM

      public static final SegmentAction MOVE_FROM
      Move a segment from this server to another. This is essentially a pending DROP operation, which starts only when the corresponding MOVE_TO has succeded.

  • Method Details

    • values

      public static SegmentAction[] values()
      Returns an array containing the constants of this enum type, in the order they are declared.
      Returns:
      an array containing the constants of this enum type, in the order they are declared

    • valueOf

      public static SegmentAction valueOf(String name)
      Returns the enum constant of this type with the specified name. The string must match exactly an identifier used to declare an enum constant in this type. (Extraneous whitespace characters are not permitted.)
      Parameters:
      name - the name of the enum constant to be returned.
      Returns:
      the enum constant with the specified name
      Throws:
      IllegalArgumentException - if this enum type has no constant with the specified name
      NullPointerException - if the argument is null

    • isLoad

      public boolean isLoad()
      True only if this action loads a segment on a server, i.e. LOAD, REPLICATE or MOVE_TO.