org.objectweb.cjdbc.controller.loadbalancer.raidb1
Class RAIDb1ec_WRR

java.lang.Object
  javax.management.StandardMBean
      org.objectweb.cjdbc.controller.jmx.AbstractStandardMBean
          org.objectweb.cjdbc.controller.loadbalancer.AbstractLoadBalancer
              org.objectweb.cjdbc.controller.loadbalancer.raidb1.RAIDb1
                  org.objectweb.cjdbc.controller.loadbalancer.raidb1.RAIDb1ec
                      org.objectweb.cjdbc.controller.loadbalancer.raidb1.RAIDb1ec_WRR

All Implemented Interfaces:

AbstractLoadBalancerMBean, javax.management.DynamicMBean, javax.management.NotificationBroadcaster, javax.management.NotificationEmitter, XmlComponent

public class RAIDb1ec_WRR

extends RAIDb1ec

RAIDb-1 Weighted Round Robin load balancer with error checking.

This load balancer tolerates byzantine failures of databases. The read requests coming from the Request Manager are sent to multiple backend nodes and the results are compared. Write requests are broadcasted to all backends.

Version:

1.0

Author:

Emmanuel Cecchet , Julie Marguerite

Nested Class Summary

Nested classes inherited from class javax.management.StandardMBean

Field Summary

private java.util.HashMap

weights

Fields inherited from class org.objectweb.cjdbc.controller.loadbalancer.raidb1.RAIDb1ec

backendReadThreads, errorCheckingPolicy, logger, nbOfConcurrentReads

Fields inherited from class org.objectweb.cjdbc.controller.loadbalancer.raidb1.RAIDb1

backendBlockingThreads, backendBlockingThreadsRWLock, backendNonBlockingThreads, backendNonBlockingThreadsRWLock, waitForCompletionPolicy

Fields inherited from class org.objectweb.cjdbc.controller.loadbalancer.AbstractLoadBalancer

macroHandler, parsingGranularity, raidbLevel, totalOrderQueue, vdb

Fields inherited from class org.objectweb.cjdbc.controller.jmx.AbstractStandardMBean

Fields inherited from class javax.management.StandardMBean

Fields inherited from interface org.objectweb.cjdbc.common.xml.XmlComponent

DOCTYPE_CONTROLLER, DOCTYPE_DB, XML_VERSION

Constructor Summary

RAIDb1ec_WRR(VirtualDatabase vdb, WaitForCompletionPolicy waitForCompletionPolicy, ErrorCheckingPolicy errorCheckingPolicy, int nbOfConcurrentReads)
Creates a new RAIDb-1 Weighted Round Robin with error checking request load balancer.

Method Summary

ControllerResultSet	execReadOnlyReadStoredProcedure(StoredProcedure proc, MetadataCache metadataCache) Not implemented.
ControllerResultSet	execReadRequest(SelectRequest request, MetadataCache metadataCache) Not implemented.
java.lang.String	getInformation() Gets information about the request load balancer.
java.lang.String	getRaidb1Xml() Surrounding raidb1 tags can be treated by getXmlImpl above, but more detailed content have to be returned by the method getRaidb1Xml below.
void	setWeight(java.lang.String name, int w) Associate a weight to a backend identified by its logical name.

Methods inherited from class org.objectweb.cjdbc.controller.loadbalancer.raidb1.RAIDb1ec

disableBackend, enableBackend, getXmlImpl

Methods inherited from class org.objectweb.cjdbc.controller.loadbalancer.raidb1.RAIDb1

begin, commit, execReadStoredProcedure, executeRequestOnBackend, executeStoredProcedureOnBackend, execWriteRequest, execWriteRequestWithKeys, execWriteStoredProcedure, getNumberOfEnabledBackends, releaseSavepoint, rollback, rollback, setSavepoint, waitForAllWritesToComplete, waitForAllWritesToComplete, waitForAllWritesToComplete

Methods inherited from class org.objectweb.cjdbc.controller.loadbalancer.AbstractLoadBalancer

executeReadStoredProcedureOnBackend, executeSelectRequestOnBackend, executeUpdateRequestOnBackend, executeUpdateRequestOnBackendWithKeys, executeWriteStoredProcedureOnBackend, getAssociatedString, getConnectionAndBeginTransaction, getParsingGranularity, getRAIDbLevel, getXml, handleMacros, removeHeadFromAndNotifyTotalOrderQueue, setMacroHandler, setParsingGranularity, setRAIDbLevel, waitForTotalOrder

Methods inherited from class org.objectweb.cjdbc.controller.jmx.AbstractStandardMBean

addNotificationListener, getDescription, getDescription, getDescription, getDescription, getDescription, getDescription, getNotificationInfo, getParameterName, getParameterName, removeNotificationListener, removeNotificationListener, sendNotification

Methods inherited from class javax.management.StandardMBean

cacheMBeanInfo, getAttribute, getAttributes, getCachedMBeanInfo, getClassName, getConstructors, getDescription, getImpact, getImplementation, getImplementationClass, getMBeanInfo, getMBeanInterface, invoke, setAttribute, setAttributes, setImplementation

Methods inherited from class java.lang.Object

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

Field Detail

weights

private java.util.HashMap weights

Constructor Detail

RAIDb1ec_WRR

public RAIDb1ec_WRR(VirtualDatabase vdb,
                    WaitForCompletionPolicy waitForCompletionPolicy,
                    ErrorCheckingPolicy errorCheckingPolicy,
                    int nbOfConcurrentReads)
             throws java.lang.Exception

Creates a new RAIDb-1 Weighted Round Robin with error checking request load balancer.

Parameters:

vdb - the virtual database this load balancer belongs to.

waitForCompletionPolicy - How many backends must complete before returning the result?

errorCheckingPolicy - policy to apply for error checking.

nbOfConcurrentReads - number of concurrent reads allowed

Throws:

java.lang.Exception - if an error occurs

Method Detail

execReadRequest

public ControllerResultSet execReadRequest(SelectRequest request,
                                           MetadataCache metadataCache)
                                    throws java.sql.SQLException

Not implemented.

Specified by:

execReadRequest in class RAIDb1

Throws:

java.sql.SQLException

See Also:

RAIDb1.execReadRequest(SelectRequest, MetadataCache)

execReadOnlyReadStoredProcedure

public ControllerResultSet execReadOnlyReadStoredProcedure(StoredProcedure proc,
                                                           MetadataCache metadataCache)
                                                    throws java.sql.SQLException

Not implemented.

Specified by:

execReadOnlyReadStoredProcedure in class AbstractLoadBalancer

Parameters:

proc - the stored procedure call

metadataCache - MetadataCache (null if none)

Returns:

a ControllerResultSet value

Throws:

java.sql.SQLException - if an error occurs

See Also:

AbstractLoadBalancer.execReadOnlyReadStoredProcedure(StoredProcedure, MetadataCache)

setWeight

public void setWeight(java.lang.String name,
                      int w)
               throws java.sql.SQLException

Description copied from class: AbstractLoadBalancer

Associate a weight to a backend identified by its logical name.

Specified by:

setWeight in interface AbstractLoadBalancerMBean

Overrides:

setWeight in class AbstractLoadBalancer

Parameters:

name - the backend name

w - the weight

Throws:

java.sql.SQLException - if an error occurs

See Also:

AbstractLoadBalancer.setWeight(String, int)

getInformation

public java.lang.String getInformation()

Gets information about the request load balancer.

Specified by:

getInformation in interface AbstractLoadBalancerMBean

Specified by:

getInformation in class AbstractLoadBalancer

Returns:

String containing information

getRaidb1Xml

public java.lang.String getRaidb1Xml()

Description copied from class: RAIDb1

Surrounding raidb1 tags can be treated by getXmlImpl above, but more detailed content have to be returned by the method getRaidb1Xml below.

Specified by:

getRaidb1Xml in class RAIDb1

Returns:

content of Raidb1 xml

See Also:

RAIDb1.getRaidb1Xml()