org.apache.hadoop.hbase.master.assignment

Class MoveRegionProcedure

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<org.apache.hadoop.hbase.shaded.protobuf.generated.MasterProcedureProtos.MoveRegionState>

org.apache.hadoop.hbase.master.assignment.MoveRegionProcedure

All Implemented Interfaces:

Comparable<Procedure<MasterProcedureEnv>>, TableProcedureInterface

@InterfaceAudience.Private
public class MoveRegionProcedure
extends AbstractStateMachineRegionProcedure<org.apache.hadoop.hbase.shaded.protobuf.generated.MasterProcedureProtos.MoveRegionState>

Procedure that implements a RegionPlan. It first runs an unassign subprocedure followed by an assign subprocedure. It takes a lock on the region being moved. It holds the lock for the life of the procedure.

Throws exception on construction if determines context hostile to move (cluster going down or master is shutting down or table is disabled).

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 and Description
private static org.slf4j.Logger	LOG
private RegionPlan	plan

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

Constructor Summary

Constructors

Constructor and Description
MoveRegionProcedure()
MoveRegionProcedure(MasterProcedureEnv env, RegionPlan plan, boolean check)

Method Summary

Modifier and Type	Method and Description
boolean	abort(MasterProcedureEnv env) The abort() call is asynchronous and each procedure must decide how to deal with it, if they want to be abortable.
protected void	deserializeStateData(ProcedureStateSerializer serializer) Called on store load to allow the user to decode the previously serialized state.
protected StateMachineProcedure.Flow	executeFromState(MasterProcedureEnv env, org.apache.hadoop.hbase.shaded.protobuf.generated.MasterProcedureProtos.MoveRegionState state) called to perform a single step of the specified 'state' of the procedure
protected org.apache.hadoop.hbase.shaded.protobuf.generated.MasterProcedureProtos.MoveRegionState	getInitialState() Return the initial state object that will be used for the first call to executeFromState().
protected RegionPlan	getPlan()
protected org.apache.hadoop.hbase.shaded.protobuf.generated.MasterProcedureProtos.MoveRegionState	getState(int stateId) Convert an ordinal (or state id) to an Enum (or more descriptive) state object.
protected int	getStateId(org.apache.hadoop.hbase.shaded.protobuf.generated.MasterProcedureProtos.MoveRegionState state) Convert the Enum (or more descriptive) state object to an ordinal (or state id).
TableName	getTableName()
TableProcedureInterface.TableOperationType	getTableOperationType() Given an operation type we can take decisions about what to do with pending operations.
protected void	rollbackState(MasterProcedureEnv env, org.apache.hadoop.hbase.shaded.protobuf.generated.MasterProcedureProtos.MoveRegionState state) called to perform the rollback of the specified state
protected void	serializeStateData(ProcedureStateSerializer serializer) The user-level code of the procedure may have some state to persist (e.g.
void	toStringClassDetails(StringBuilder sb) Extend the toString() information with the procedure details e.g.
protected boolean	waitInitialized(MasterProcedureEnv env) The Procedure.doAcquireLock(Object, ProcedureStore) will be split into two steps, first, it will call us to determine whether we need to wait for initialization, second, it will call Procedure.acquireLock(Object) to actually handle the lock for this procedure.

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

acquireLock, checkTableModifiable, getRegion, holdLock, releaseLock, setFailure, setRegion

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

checkOnline, getRegionDir, getUser, getWALRegionDir, preflightChecks, releaseSyncLatch, setUser

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

addChildProcedure, execute, failIfAborted, getCurrentState, getCurrentStateId, getCycles, isEofState, isRollbackSupported, isYieldAfterExecutionStep, isYieldBeforeExecuteFromState, rollback, 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, setFailure, setFailure, setLastUpdate, setNonceKey, setOwner, setOwner, setParentProcId, setProcId, setResult, setRootProcId, setStackIndexes, setState, setSubmittedTime, setTimeout, setTimeoutFailure, shouldWaitClientAck, skipPersistence, 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 Detail

LOG

private static final org.slf4j.Logger LOG

plan

private RegionPlan plan

Constructor Detail

MoveRegionProcedure

public MoveRegionProcedure()

MoveRegionProcedure

public MoveRegionProcedure(MasterProcedureEnv env,
                           RegionPlan plan,
                           boolean check)
                    throws HBaseIOException

Parameters:

check - whether we should do some checks in the constructor. We will skip the checks if we are reopening a region as this may fail the whole procedure and cause stuck. We will do the check later when actually executing the procedure so not a big problem.

Throws:

IOException - If the cluster is offline or master is stopping or if table is disabled or non-existent.

HBaseIOException

Method Detail

getPlan

protected RegionPlan getPlan()

executeFromState

protected StateMachineProcedure.Flow executeFromState(MasterProcedureEnv env,
                                                      org.apache.hadoop.hbase.shaded.protobuf.generated.MasterProcedureProtos.MoveRegionState state)
                                               throws InterruptedException

Description copied from class: StateMachineProcedure

called to perform a single step of the specified 'state' of the procedure

Specified by:

executeFromState in class StateMachineProcedure<MasterProcedureEnv,org.apache.hadoop.hbase.shaded.protobuf.generated.MasterProcedureProtos.MoveRegionState>

state - state to execute

Returns:

Flow.NO_MORE_STATE if the procedure is completed, Flow.HAS_MORE_STATE if there is another step.

Throws:

InterruptedException

rollbackState

protected void rollbackState(MasterProcedureEnv env,
                             org.apache.hadoop.hbase.shaded.protobuf.generated.MasterProcedureProtos.MoveRegionState state)
                      throws IOException

Description copied from class: StateMachineProcedure

called to perform the rollback of the specified state

Specified by:

rollbackState in class StateMachineProcedure<MasterProcedureEnv,org.apache.hadoop.hbase.shaded.protobuf.generated.MasterProcedureProtos.MoveRegionState>

state - state to rollback

Throws:

IOException - temporary failure, the rollback will retry later

abort

public boolean abort(MasterProcedureEnv env)

Description copied from class: Procedure

The abort() call is asynchronous and each procedure must decide how to deal with it, if they want to be abortable. The simplest implementation is to have an AtomicBoolean set in the abort() method and then the execute() will check if the abort flag is set or not. abort() may be called multiple times from the client, so the implementation must be idempotent.

NOTE: abort() is not like Thread.interrupt(). It is just a notification that allows the procedure implementor abort.

Overrides:

abort in class StateMachineProcedure<MasterProcedureEnv,org.apache.hadoop.hbase.shaded.protobuf.generated.MasterProcedureProtos.MoveRegionState>

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 AbstractStateMachineRegionProcedure<org.apache.hadoop.hbase.shaded.protobuf.generated.MasterProcedureProtos.MoveRegionState>

Parameters:

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

getInitialState

protected org.apache.hadoop.hbase.shaded.protobuf.generated.MasterProcedureProtos.MoveRegionState getInitialState()

Description copied from class: StateMachineProcedure

Return the initial state object that will be used for the first call to executeFromState().

Specified by:

getInitialState in class StateMachineProcedure<MasterProcedureEnv,org.apache.hadoop.hbase.shaded.protobuf.generated.MasterProcedureProtos.MoveRegionState>

Returns:

the initial state enum object

getStateId

protected int getStateId(org.apache.hadoop.hbase.shaded.protobuf.generated.MasterProcedureProtos.MoveRegionState state)

Description copied from class: StateMachineProcedure

Convert the Enum (or more descriptive) state object to an ordinal (or state id).

Specified by:

getStateId in class StateMachineProcedure<MasterProcedureEnv,org.apache.hadoop.hbase.shaded.protobuf.generated.MasterProcedureProtos.MoveRegionState>

Parameters:

state - the state enum object

Returns:

stateId the ordinal() of the state enum (or state id)

getState

protected org.apache.hadoop.hbase.shaded.protobuf.generated.MasterProcedureProtos.MoveRegionState getState(int stateId)

Description copied from class: StateMachineProcedure

Convert an ordinal (or state id) to an Enum (or more descriptive) state object.

Specified by:

getState in class StateMachineProcedure<MasterProcedureEnv,org.apache.hadoop.hbase.shaded.protobuf.generated.MasterProcedureProtos.MoveRegionState>

Parameters:

stateId - the ordinal() of the state enum (or state id)

Returns:

the state enum object

getTableName

public TableName getTableName()

Specified by:

getTableName in interface TableProcedureInterface

Overrides:

getTableName in class AbstractStateMachineRegionProcedure<org.apache.hadoop.hbase.shaded.protobuf.generated.MasterProcedureProtos.MoveRegionState>

Returns:

the name of the table the procedure is operating on

getTableOperationType

public 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 AbstractStateMachineRegionProcedure<org.apache.hadoop.hbase.shaded.protobuf.generated.MasterProcedureProtos.MoveRegionState>

Returns:

the operation type that the procedure is executing.

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 AbstractStateMachineRegionProcedure<org.apache.hadoop.hbase.shaded.protobuf.generated.MasterProcedureProtos.MoveRegionState>

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 AbstractStateMachineRegionProcedure<org.apache.hadoop.hbase.shaded.protobuf.generated.MasterProcedureProtos.MoveRegionState>

Parameters:

serializer - contains the serialized state

Throws:

IOException

waitInitialized

protected boolean waitInitialized(MasterProcedureEnv env)

Description copied from class: Procedure

The Procedure.doAcquireLock(Object, ProcedureStore) will be split into two steps, first, it will call us to determine whether we need to wait for initialization, second, it will call Procedure.acquireLock(Object) to actually handle the lock for this procedure.

This is because that when master restarts, we need to restore the lock state for all the procedures to not break the semantic if Procedure.holdLock(Object) is true. But the ProcedureExecutor will be started before the master finish initialization(as it is part of the initialization!), so we need to split the code into two steps, and when restore, we just restore the lock part and ignore the waitInitialized part. Otherwise there will be dead lock.

Overrides:

waitInitialized in class AbstractStateMachineTableProcedure<org.apache.hadoop.hbase.shaded.protobuf.generated.MasterProcedureProtos.MoveRegionState>

Returns:

true means we need to wait until the environment has been initialized, otherwise true.