Package org.apache.hadoop.hbase.master.procedure

Class AbstractStateMachineRegionProcedure<TState>

java.lang.Object

org.apache.hadoop.hbase.procedure2.Procedure<TEnvironment>

org.apache.hadoop.hbase.procedure2.StateMachineProcedure<MasterProcedureEnv,TState>

org.apache.hadoop.hbase.master.procedure.AbstractStateMachineTableProcedure<TState>

org.apache.hadoop.hbase.master.procedure.AbstractStateMachineRegionProcedure<TState>

All Implemented Interfaces:

Comparable<Procedure<MasterProcedureEnv>>, TableProcedureInterface

Direct Known Subclasses:

GCRegionProcedure, MoveRegionProcedure, SplitTableRegionProcedure, TransitRegionStateProcedure, TruncateRegionProcedure

@Private
public abstract class AbstractStateMachineRegionProcedure<TState>
extends AbstractStateMachineTableProcedure<TState>

Base class for all the Region procedures that want to use a StateMachine. It provides some basic helpers like basic locking, sync latch, and toStringClassDetails(). Defaults to holding the lock for the life of the procedure.

Nested Class Summary

Nested classes/interfaces inherited from class org.apache.hadoop.hbase.procedure2.StateMachineProcedure

StateMachineProcedure.Flow

Nested classes/interfaces inherited from class org.apache.hadoop.hbase.procedure2.Procedure

Procedure.LockState

Nested classes/interfaces inherited from interface org.apache.hadoop.hbase.master.procedure.TableProcedureInterface

TableProcedureInterface.TableOperationType

Field Summary

Fields

Modifier and Type	Field	Description
private RegionInfo	hri

Fields inherited from class org.apache.hadoop.hbase.procedure2.StateMachineProcedure

stateCount

Fields inherited from class org.apache.hadoop.hbase.procedure2.Procedure

NO_PROC_ID, NO_TIMEOUT

Fields inherited from interface org.apache.hadoop.hbase.master.procedure.TableProcedureInterface

DUMMY_NAMESPACE_TABLE_NAME

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	AbstractStateMachineRegionProcedure()
protected	AbstractStateMachineRegionProcedure(MasterProcedureEnv env, RegionInfo hri)
protected	AbstractStateMachineRegionProcedure(MasterProcedureEnv env, RegionInfo hri, ProcedurePrepareLatch latch)

Method Summary

Modifier and Type	Method	Description
protected Procedure.LockState	acquireLock(MasterProcedureEnv env)	The user should override this method if they need a lock on an Entity.
protected void	deserializeStateData(ProcedureStateSerializer serializer)	Called on store load to allow the user to decode the previously serialized state.
RegionInfo	getRegion()	Returns The RegionInfo of the region we are operating on.
TableName	getTableName()	Returns the name of the table the procedure is operating on
abstract TableProcedureInterface.TableOperationType	getTableOperationType()	Given an operation type we can take decisions about what to do with pending operations.
protected boolean	holdLock(MasterProcedureEnv env)	Used to keep the procedure lock even when the procedure is yielding or suspended.
protected void	releaseLock(MasterProcedureEnv env)	The user should override this method, and release lock if necessary.
protected void	serializeStateData(ProcedureStateSerializer serializer)	The user-level code of the procedure may have some state to persist (e.g.
protected void	setFailure(Throwable cause)
protected void	setRegion(RegionInfo hri)	Used when deserializing.
void	toStringClassDetails(StringBuilder sb)	Extend the toString() information with the procedure details e.g.

Methods inherited from class org.apache.hadoop.hbase.master.procedure.AbstractStateMachineTableProcedure

checkOnline, checkTableModifiable, getUser, getWALRegionDir, isTableEnabled, preflightChecks, releaseSyncLatch, setUser, waitInitialized

Methods inherited from class org.apache.hadoop.hbase.procedure2.StateMachineProcedure

abort, addChildProcedure, execute, executeFromState, failIfAborted, getCurrentState, getCurrentStateId, getCycles, getInitialState, getState, getStateId, isEofState, isRollbackSupported, isRollbackSupported, isYieldAfterExecutionStep, isYieldBeforeExecuteFromState, rollback, rollbackState, setNextState, toStringState

Methods inherited from class org.apache.hadoop.hbase.procedure2.Procedure

addStackIndex, afterReplay, beforeReplay, bypass, compareTo, completionCleanup, doExecute, doRollback, elapsedTime, getChildrenLatch, getException, getLastUpdate, getNonceKey, getOwner, getParentProcId, getProcedureMetrics, getProcId, getProcIdHashCode, getProcName, getResult, getRootProcedureId, getRootProcId, getStackIndexes, getState, getSubmittedTime, getTimeout, getTimeoutTimestamp, hasChildren, hasException, hasLock, hasOwner, hasParent, hasTimeout, haveSameParent, incChildrenLatch, isBypass, isFailed, isFinished, isInitializing, isLockedWhenLoading, isRunnable, isSuccess, isWaiting, removeStackIndex, setAbortFailure, setChildrenLatch, setExecuted, setFailure, setFailure, setLastUpdate, setNonceKey, setOwner, setOwner, setParentProcId, setProcId, setResult, setRootProcId, setStackIndexes, setState, setSubmittedTime, setTimeout, setTimeoutFailure, shouldWaitClientAck, skipPersistence, suspend, toString, toStringClass, toStringDetails, toStringSimpleSB, updateMetricsOnFinish, updateMetricsOnSubmit, updateTimestamp, wasExecuted

Methods inherited from class java.lang.Object

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

Field Details

hri

private RegionInfo hri

Constructor Details

AbstractStateMachineRegionProcedure

protected AbstractStateMachineRegionProcedure(MasterProcedureEnv env,
 RegionInfo hri)

AbstractStateMachineRegionProcedure

protected AbstractStateMachineRegionProcedure(MasterProcedureEnv env,
 RegionInfo hri,
 ProcedurePrepareLatch latch)

AbstractStateMachineRegionProcedure

protected AbstractStateMachineRegionProcedure()

Method Details

getRegion

public RegionInfo getRegion()

Returns The RegionInfo of the region we are operating on.

setRegion

protected void setRegion(RegionInfo hri)

Used when deserializing. Otherwise, DON'T TOUCH IT!

getTableName

public TableName getTableName()

Description copied from interface: TableProcedureInterface

Returns the name of the table the procedure is operating on

Specified by:

getTableName in interface TableProcedureInterface

Specified by:

getTableName in class AbstractStateMachineTableProcedure<TState>

getTableOperationType

public abstract TableProcedureInterface.TableOperationType getTableOperationType()

Description copied from interface: TableProcedureInterface

Given an operation type we can take decisions about what to do with pending operations. e.g. if we get a delete and we have some table operation pending (e.g. add column) we can abort those operations.

Specified by:

getTableOperationType in interface TableProcedureInterface

Specified by:

getTableOperationType in class AbstractStateMachineTableProcedure<TState>

Returns:

the operation type that the procedure is executing.

toStringClassDetails

public void toStringClassDetails(StringBuilder sb)

Description copied from class: Procedure

Extend the toString() information with the procedure details e.g. className and parameters

Overrides:

toStringClassDetails in class AbstractStateMachineTableProcedure<TState>

Parameters:

sb - the string builder to use to append the proc specific information

holdLock

protected boolean holdLock(MasterProcedureEnv env)

Description copied from class: Procedure

Used to keep the procedure lock even when the procedure is yielding or suspended.

Overrides:

holdLock in class Procedure<MasterProcedureEnv>

Returns:

true if the procedure should hold on the lock until completionCleanup()

acquireLock

protected Procedure.LockState acquireLock(MasterProcedureEnv env)

Description copied from class: Procedure

The user should override this method if they need a lock on an Entity. A lock can be anything, and it is up to the implementor. The Procedure Framework will call this method just before it invokes Procedure.execute(Object). It calls Procedure.releaseLock(Object) after the call to execute.

If you need to hold the lock for the life of the Procedure -- i.e. you do not want any other Procedure interfering while this Procedure is running, see Procedure.holdLock(Object).

Example: in our Master we can execute request in parallel for different tables. We can create t1 and create t2 and these creates can be executed at the same time. Anything else on t1/t2 is queued waiting that specific table create to happen.

There are 3 LockState:

• LOCK_ACQUIRED should be returned when the proc has the lock and the proc is ready to execute.
• LOCK_YIELD_WAIT should be returned when the proc has not the lock and the framework should take care of readding the procedure back to the runnable set for retry
• LOCK_EVENT_WAIT should be returned when the proc has not the lock and someone will take care of readding the procedure back to the runnable set when the lock is available.

Overrides:

acquireLock in class AbstractStateMachineTableProcedure<TState>

Returns:

the lock state as described above.

releaseLock

protected void releaseLock(MasterProcedureEnv env)

Description copied from class: Procedure

The user should override this method, and release lock if necessary.

Overrides:

releaseLock in class AbstractStateMachineTableProcedure<TState>

setFailure

protected void setFailure(Throwable cause)

serializeStateData

protected void serializeStateData(ProcedureStateSerializer serializer)
                           throws IOException

Description copied from class: Procedure

The user-level code of the procedure may have some state to persist (e.g. input arguments or current position in the processing state) to be able to resume on failure.

Overrides:

serializeStateData in class StateMachineProcedure<MasterProcedureEnv,TState>

Parameters:

serializer - stores the serializable state

Throws:

IOException

deserializeStateData

protected void deserializeStateData(ProcedureStateSerializer serializer)
                             throws IOException

Description copied from class: Procedure

Called on store load to allow the user to decode the previously serialized state.

Overrides:

deserializeStateData in class StateMachineProcedure<MasterProcedureEnv,TState>

Parameters:

serializer - contains the serialized state

Throws:

IOException