com.bigdata.service
Class MetadataService.DropScaleOutIndexTask

java.lang.Object
  com.bigdata.journal.AbstractTask
      com.bigdata.service.MetadataService.DropScaleOutIndexTask

All Implemented Interfaces:

ITask, Callable

Enclosing class:

MetadataService

public static class MetadataService.DropScaleOutIndexTask
extends AbstractTask

Drops a scale-out index.

Since this task is unisolated, it basically has a lock on the writable version of the metadata index. It drops each index partition and finally drops the metadata index itself.

Historical reads against the metadata index will continue to succeed both during and after this operation has completed successfully. However, ITx.READ_COMMITTED operations will succeed only until this operation completes at which point the scale-out index will no longer be visible.

The data comprising the scale-out index will remain available for historical reads until it is released by whatever policy is in effect for the ResourceManagers for the DataServices on which that data resides.

TODO:

This does not try to handle errors gracefully. E.g., if there is a problem with one of the data services hosting an index partition it does not fail over to the next data service for that index partition.

Nested Class Summary

Nested classes/interfaces inherited from class com.bigdata.journal.AbstractTask

AbstractTask.DelegateTask<T>, AbstractTask.InnerReadWriteTxServiceCallable, AbstractTask.InnerWriteServiceCallable<T>, AbstractTask.ResubmitException

Field Summary

Fields inherited from class com.bigdata.journal.AbstractTask

checkpointNanoTime, concurrencyManager, DEBUG, INFO, isReadWriteTx, log, nanoTime_assignedWorker, nanoTime_beginWork, nanoTime_finishedWork, nanoTime_submitTask, readOnly, resourceManager, taskCounters, timestamp, transactionManager, tx

Constructor Summary

protected

MetadataService.DropScaleOutIndexTask(IBigdataFederation fed, ConcurrencyManager concurrencyManager, String name)

Method Summary

protected Object

doTask() Drops the index partitions and then drops the metadata index as well.

Methods inherited from class com.bigdata.journal.AbstractTask

assertResource, assertRunning, assertUnisolated, call, clearLoggingContext, dropIndex, getCommitTime, getIndex, getJournal, getOnlyResource, getResource, getResourceManager, getTaskCounters, getTaskName, getTimestamp, isResource, registerIndex, setupLoggingContext, toString

Methods inherited from class java.lang.Object

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

Constructor Detail

MetadataService.DropScaleOutIndexTask

protected MetadataService.DropScaleOutIndexTask(IBigdataFederation fed,
                                                ConcurrencyManager concurrencyManager,
                                                String name)

Parameters:

journal -

name - The name of the metadata index for some scale-out index.

Method Detail

doTask

protected Object doTask()
                 throws Exception

Drops the index partitions and then drops the metadata index as well.

Specified by:

doTask in class AbstractTask

Returns:

The Integer #of index partitions that were dropped.

Throws:

Exception - The exception that will be thrown by AbstractTask.call() iff the operation fails.

InterruptedException - This exception SHOULD be thrown if Thread.interrupted() becomes true during execution.