org.apache.hadoop.hbase.master.procedure

Class AbstractStateMachineTableProcedure<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>

All Implemented Interfaces:

Comparable<Procedure<MasterProcedureEnv>>, TableProcedureInterface

Direct Known Subclasses:

AbstractStateMachineRegionProcedure, CloneSnapshotProcedure, CreateTableProcedure, DeleteTableProcedure, DisableTableProcedure, EnableTableProcedure, GCMergedRegionsProcedure, GCMultipleMergedRegionsProcedure, InitMetaProcedure, MergeTableRegionsProcedure, ModifyTableProcedure, ReopenTableRegionsProcedure, RestoreSnapshotProcedure, TruncateTableProcedure

@InterfaceAudience.Private
public abstract class AbstractStateMachineTableProcedure<TState>
extends StateMachineProcedure<MasterProcedureEnv,TState>
implements TableProcedureInterface

Base class for all the Table procedures that want to use a StateMachineProcedure. It provides helpers like basic locking, sync latch, and toStringClassDetails().

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 ProcedurePrepareLatch	syncLatch
private User	user

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

Modifier	Constructor and Description
protected	AbstractStateMachineTableProcedure()
protected	AbstractStateMachineTableProcedure(MasterProcedureEnv env)
protected	AbstractStateMachineTableProcedure(MasterProcedureEnv env, ProcedurePrepareLatch latch)

Method Summary

Modifier and Type	Method and Description
protected Procedure.LockState	acquireLock(MasterProcedureEnv env) The user should override this method if they need a lock on an Entity.
protected static void	checkOnline(MasterProcedureEnv env, RegionInfo ri) Check region is online.
protected void	checkTableModifiable(MasterProcedureEnv env) Check whether a table is modifiable - exists and either offline or online with config set
abstract TableName	getTableName()
abstract TableProcedureInterface.TableOperationType	getTableOperationType() Given an operation type we can take decisions about what to do with pending operations.
protected User	getUser()
protected org.apache.hadoop.fs.Path	getWALRegionDir(MasterProcedureEnv env, RegionInfo region)
protected void	preflightChecks(MasterProcedureEnv env, Boolean enabled) Check that cluster is up and master is running.
protected void	releaseLock(MasterProcedureEnv env) The user should override this method, and release lock if necessary.
protected void	releaseSyncLatch()
protected void	setUser(User user)
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.procedure2.StateMachineProcedure

abort, addChildProcedure, deserializeStateData, execute, executeFromState, failIfAborted, getCurrentState, getCurrentStateId, getCycles, getInitialState, getState, getStateId, isEofState, isRollbackSupported, isYieldAfterExecutionStep, isYieldBeforeExecuteFromState, rollback, rollbackState, serializeStateData, 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, holdLock, 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

syncLatch

private final ProcedurePrepareLatch syncLatch

user

private User user

Constructor Detail

AbstractStateMachineTableProcedure

protected AbstractStateMachineTableProcedure()

AbstractStateMachineTableProcedure

protected AbstractStateMachineTableProcedure(MasterProcedureEnv env)

AbstractStateMachineTableProcedure

protected AbstractStateMachineTableProcedure(MasterProcedureEnv env,
                                             ProcedurePrepareLatch latch)

Parameters:

env - Uses this to set Procedure Owner at least.

Method Detail

getTableName

public abstract TableName getTableName()

Specified by:

getTableName in interface TableProcedureInterface

Returns:

the name of the table the procedure is operating on

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

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 Procedure<MasterProcedureEnv>

Parameters:

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

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 Procedure<MasterProcedureEnv>

Returns:

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

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 Procedure<MasterProcedureEnv>

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 Procedure<MasterProcedureEnv>

getUser

protected User getUser()

setUser

protected void setUser(User user)

releaseSyncLatch

protected void releaseSyncLatch()

checkTableModifiable

protected void checkTableModifiable(MasterProcedureEnv env)
                             throws IOException

Check whether a table is modifiable - exists and either offline or online with config set

Parameters:

env - MasterProcedureEnv

Throws:

IOException

getWALRegionDir

protected final org.apache.hadoop.fs.Path getWALRegionDir(MasterProcedureEnv env,
                                                          RegionInfo region)
                                                   throws IOException

Throws:

IOException

preflightChecks

protected void preflightChecks(MasterProcedureEnv env,
                               Boolean enabled)
                        throws HBaseIOException

Check that cluster is up and master is running. Check table is modifiable. If enabled, check table is enabled else check it is disabled. Call in Procedure constructor so can pass any exception to caller.

Parameters:

enabled - If true, check table is enabled and throw exception if not. If false, do the inverse. If null, do no table checks.

Throws:

HBaseIOException

checkOnline

protected static void checkOnline(MasterProcedureEnv env,
                                  RegionInfo ri)
                           throws DoNotRetryRegionException

Check region is online.

Throws:

DoNotRetryRegionException