Package org.apache.accumulo.core.spi.balancer

Interface TabletBalancer.BalanceParameters

Enclosing interface:
TabletBalancer
public static interface TabletBalancer.BalanceParameters
An interface for grouping parameters required for the balancer to balance tablets. This interface allows for evolution of the parameter set without changing the balancer's method signature.
Since:
2.1.0

  • Method Details

    • currentStatus

      SortedMap<TabletServerId,TServerStatus> currentStatus()
      Returns:
      the current status for all tablet servers (read-only)

    • currentMigrations

      Set<TabletId> currentMigrations()
      Returns:
      the migrations that are currently in progress (read-only)

    • migrationsOut

      List<TabletMigration> migrationsOut()
      Returns:
      a write-only map for storing new assignments made by the balancer. It is important that any tablets found in currentMigrations() are not included in the output migrations.

    • partitionName

      String partitionName()
      Accumulo may partition tables in different ways and pass subsets of tables to the balancer via getTablesToBalance(). Each partition is given a unique name that is always the same for a given partition. Balancer can use this to determine if they are being called for the same or a different partition if tracking state between balance calls.
      Returns:
      name of current partition of tables to balance.
      Since:
      2.1.4

    • getTablesToBalance

      Map<String,TableId> getTablesToBalance()
      This is the set of tables the balancer should consider. Balancing any tables outside of this set will be ignored and result in an error in the logs.
      Returns:
      map of table names to table ids that should be balanced.
      Since:
      2.1.4