com.orientechnologies.orient.core.db

Class OPartitionedDatabasePool

java.lang.Object

com.orientechnologies.orient.core.OOrientListenerAbstract

com.orientechnologies.orient.core.db.OPartitionedDatabasePool

All Implemented Interfaces:

OOrientListener, OOrientShutdownListener, OOrientStartupListener

public class OPartitionedDatabasePool
extends OOrientListenerAbstract

Database pool which has good multicore scalability characteristics because of creation of several partitions for each logical thread group which drastically decrease thread contention when we acquire new connection to database.

To acquire connection from the pool call acquire() method but to release connection you just need to call ODatabase.close() method.

In case of remote storage database pool will keep connections to the remote storage till you close pool. So in case of remote storage you should close pool at the end of it's usage, it also may be closed on application shutdown but you should not rely on this behaviour.

This pool has one noticeable difference from other pools. If you perform several subsequent acquire calls in the same thread the same instance of database will be returned, but amount of calls to close method should match to amount of acquire calls to release database back in the pool. It will allow you to use such feature as transaction propagation when you perform call of one service from another one.

Given pool has two parameters now, amount of maximum connections for single partition and total amount of connections which may be hold by pool. When you start to use pool it will automatically split by several partitions, each partition is independent from other which gives us very good multicore scalability. Amount of partitions will be close to amount of cores but it is not mandatory and depends how much application is loaded. Amount of connections which may be hold by single partition is defined by user but we suggest to use default parameters if your application load is not extremely high.

If total amount of connections which allowed to be hold by this pool is reached thread will wait till free connection will be available. If total amount of connection is set to value 0 or less it means that there is no connection limit.

Since:

06/11/14

Author:

Andrey Lomakin (a.lomakin-at-orientdb.com)

Field Summary

Fields

Modifier and Type	Field and Description
protected Map<String,Object>	properties

Constructor Summary

Constructors

Constructor and Description
OPartitionedDatabasePool(String url, String userName, String password)
OPartitionedDatabasePool(String url, String userName, String password, int maxPartitionSize, int maxPoolSize)

Method Summary

Modifier and Type	Method and Description
ODatabaseDocumentTx	acquire()
void	close()
int	getAvailableConnections()
int	getCreatedInstances()
int	getMaxPartitonSize()
Object	getProperty(String iName) Gets the property value.
String	getUrl()
String	getUserName()
boolean	isAutoCreate()
boolean	isClosed()
void	onShutdown()
void	onStartup()
protected void	openDatabase(com.orientechnologies.orient.core.db.OPartitionedDatabasePool.DatabaseDocumentTxPooled db)
OPartitionedDatabasePool	setAutoCreate(boolean autoCreate)
Object	setProperty(String iName, Object iValue) Sets a property value

Methods inherited from class com.orientechnologies.orient.core.OOrientListenerAbstract

onStorageRegistered, onStorageUnregistered

Methods inherited from class java.lang.Object

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

Field Detail

properties

protected final Map<String,Object> properties

Constructor Detail

OPartitionedDatabasePool

public OPartitionedDatabasePool(String url,
                                String userName,
                                String password)

OPartitionedDatabasePool

public OPartitionedDatabasePool(String url,
                                String userName,
                                String password,
                                int maxPartitionSize,
                                int maxPoolSize)

Method Detail

getUrl

public String getUrl()

getUserName

public String getUserName()

getMaxPartitonSize

public int getMaxPartitonSize()

getAvailableConnections

public int getAvailableConnections()

getCreatedInstances

public int getCreatedInstances()

acquire

public ODatabaseDocumentTx acquire()

isAutoCreate

public boolean isAutoCreate()

setAutoCreate

public OPartitionedDatabasePool setAutoCreate(boolean autoCreate)

isClosed

public boolean isClosed()

openDatabase

protected void openDatabase(com.orientechnologies.orient.core.db.OPartitionedDatabasePool.DatabaseDocumentTxPooled db)

onShutdown

public void onShutdown()

Specified by:

onShutdown in interface OOrientListener

Specified by:

onShutdown in interface OOrientShutdownListener

Overrides:

onShutdown in class OOrientListenerAbstract

onStartup

public void onStartup()

Specified by:

onStartup in interface OOrientStartupListener

Overrides:

onStartup in class OOrientListenerAbstract

close

public void close()

setProperty

public Object setProperty(String iName,
                          Object iValue)

Sets a property value

Parameters:

iName - Property name

iValue - new value to set

Returns:

The previous value if any, otherwise null

getProperty

public Object getProperty(String iName)

Gets the property value.

Parameters:

iName - Property name

Returns:

The previous value if any, otherwise null