org.apache.hadoop.hbase.master.procedure

Class MasterProcedureQueue

java.lang.Object

org.apache.hadoop.hbase.master.procedure.MasterProcedureQueue

All Implemented Interfaces:

ProcedureRunnableSet

@InterfaceAudience.Private
@InterfaceStability.Evolving
public class MasterProcedureQueue
extends Object
implements ProcedureRunnableSet

ProcedureRunnableSet for the Master Procedures. This RunnableSet tries to provide to the ProcedureExecutor procedures that can be executed without having to wait on a lock. Most of the master operations can be executed concurrently, if the they are operating on different tables (e.g. two create table can be performed at the same, time assuming table A and table B). Each procedure should implement an interface providing information for this queue. for example table related procedures should implement TableProcedureInterface. each procedure will be pushed in its own queue, and based on the operation type we may take smarter decision. e.g. we can abort all the operations preceding a delete table, or similar.

Constructor Summary

Constructors

Constructor and Description
MasterProcedureQueue(org.apache.hadoop.conf.Configuration conf, TableLockManager lockManager)

Method Summary

Methods

Modifier and Type	Method and Description
void	addBack(Procedure proc)
void	addFront(Procedure proc)
void	clear()
void	completionCleanup(Procedure proc)
protected boolean	markTableAsDeleted(TableName table) Tries to remove the queue and the table-lock of the specified table.
Long	poll()
void	releaseTableRead(TableName table) Release the read lock taken with tryAcquireTableRead()
void	releaseTableWrite(TableName table) Release the write lock taken with tryAcquireTableWrite()
void	signalAll()
int	size()
String	toString()
boolean	tryAcquireTableRead(TableName table, String purpose) Try to acquire the read lock on the specified table.
boolean	tryAcquireTableWrite(TableName table, String purpose) Try to acquire the write lock on the specified table.
void	yield(Procedure proc)

Methods inherited from class java.lang.Object

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

Constructor Detail

MasterProcedureQueue

public MasterProcedureQueue(org.apache.hadoop.conf.Configuration conf,
                    TableLockManager lockManager)

Method Detail

addFront

public void addFront(Procedure proc)

Specified by:

addFront in interface ProcedureRunnableSet

addBack

public void addBack(Procedure proc)

Specified by:

addBack in interface ProcedureRunnableSet

yield

public void yield(Procedure proc)

Specified by:

yield in interface ProcedureRunnableSet

poll

public Long poll()

Specified by:

poll in interface ProcedureRunnableSet

signalAll

public void signalAll()

Specified by:

signalAll in interface ProcedureRunnableSet

clear

public void clear()

Specified by:

clear in interface ProcedureRunnableSet

size

public int size()

Specified by:

size in interface ProcedureRunnableSet

toString

public String toString()

Overrides:

toString in class Object

completionCleanup

public void completionCleanup(Procedure proc)

Specified by:

completionCleanup in interface ProcedureRunnableSet

tryAcquireTableRead

public boolean tryAcquireTableRead(TableName table,
                          String purpose)

Try to acquire the read lock on the specified table. other read operations in the table-queue may be executed concurrently, otherwise they have to wait until all the read-locks are released.

Parameters:

table - Table to lock

purpose - Human readable reason for locking the table

Returns:

true if we were able to acquire the lock on the table, otherwise false.

releaseTableRead

public void releaseTableRead(TableName table)

Release the read lock taken with tryAcquireTableRead()

Parameters:

table - the name of the table that has the read lock

tryAcquireTableWrite

public boolean tryAcquireTableWrite(TableName table,
                           String purpose)

Try to acquire the write lock on the specified table. other operations in the table-queue will be executed after the lock is released.

Parameters:

table - Table to lock

purpose - Human readable reason for locking the table

Returns:

true if we were able to acquire the lock on the table, otherwise false.

releaseTableWrite

public void releaseTableWrite(TableName table)

Release the write lock taken with tryAcquireTableWrite()

Parameters:

table - the name of the table that has the write lock

markTableAsDeleted

protected boolean markTableAsDeleted(TableName table)

Tries to remove the queue and the table-lock of the specified table. If there are new operations pending (e.g. a new create), the remove will not be performed.

Parameters:

table - the name of the table that should be marked as deleted

Returns:

true if deletion succeeded, false otherwise meaning that there are other new operations pending for that table (e.g. a new create).