Full Import: An error occurred while evaluating a task on a worker thread. Error code 40174

In IDaaS the full import of a chris21 connector is receiving an error as logged in the log file as follows. It seems to point to a problem with SQL Error code 40174.

The cause was identified as a result of throttling on Azure DB.

Solution: Increasing the DTU capacity on the DB in Azure.

Connector Processing started for connector chris21 - POS Form (page 15)",Normal
20151023,04:20:58,UNIFY Identity Broker,List,Information,Next chunk is [1000] sub total [19000]. Duration: 00:00:10.2657290,Normal
20151023,04:21:00,UNIFY Identity Broker,Change detection engine,Information,"Started processing changes register items.
Started processing changes register items for connector chris21 - POS Form.",Normal
20151023,04:21:01,UNIFY Identity Broker,Change detection engine,Information,"Changes register item processing completed.
Changes register item processing on connector chris21 - POS Form completed.  Duration: 00:00:01.1719116",Normal
20151023,04:21:07,UNIFY Identity Broker,Connector Processor,Information,"Connector processing failed.
Connector Processing page 15 for connector chris21 - POS Form failed with reason The service has encountered an error processing your request. Please try again. Error code 40174.
A severe error occurred on the current command.  The results, if any, should be discarded.. Duration: 00:00:09.7625532. 
Error details:
System.Data.SqlClient.SqlException (0x80131904): The service has encountered an error processing your request. Please try again. Error code 40174.
A severe error occurred on the current command.  The results, if any, should be discarded.
   at System.Data.SqlClient.SqlConnection.OnError(SqlException exception, Boolean breakConnection, Action`1 wrapCloseInAction)
   at System.Data.SqlClient.TdsParser.ThrowExceptionAndWarning(TdsParserStateObject stateObj, Boolean callerHasConnectionLock, Boolean asyncClose)
   at System.Data.SqlClient.TdsParser.TryRun(RunBehavior runBehavior, SqlCommand cmdHandler, SqlDataReader dataStream, BulkCopySimpleResultSet bulkCopyHandler, TdsParserStateObject stateObj, Boolean& dataReady)
   at System.Data.SqlClient.SqlDataReader.TryHasMoreRows(Boolean& moreRows)
   at System.Data.SqlClient.SqlDataReader.TryReadInternal(Boolean setTimeout, Boolean& more)
   at System.Data.SqlClient.SqlDataReader.Read()
   at System.Data.Linq.SqlClient.ObjectReaderCompiler.ObjectReaderBase`1.Read()
   at System.Data.Linq.SqlClient.ObjectReaderCompiler.ObjectReader`2.MoveNext()
   at System.Linq.Enumerable.WhereSelectEnumerableIterator`2.MoveNext()
   at System.Linq.Buffer`1..ctor(IEnumerable`1 source)
   at System.Linq.Enumerable.ToArray[TSource](IEnumerable`1 source)
   at Unify.Framework.Data.LinqWhereQuery`5.GetEnumerator()
   at System.Linq.Buffer`1..ctor(IEnumerable`1 source)
   at System.Linq.Enumerable.ToArray[TSource](IEnumerable`1 source)
   at Unify.Product.IdentityBroker.EntityRepositoryExtensions.ConvertConnectorEntitiesWithRepositoryEntities(IEnumerable`1 connectorEntities, IMultiKey`1 schemaKey, IQueryable`1 sourceEntities, Guid connectorId, IEnumerable`1 originalEntities)
   at Unify.Product.IdentityBroker.RepositoryChangeDetectionWorkerBase.PerformChangeDetectionOnConnectorEntityPage(IEnumerable`1 connectorEntities, Int32& index, Int32 entitiesProcessedSoFar, IEntityChangesReportGenerator`2 reportGenerator)
   at Unify.Product.IdentityBroker.RepositoryChangeDetectionWorkerBase.<>c__DisplayClass3.<PerformChangeDetection>b__0(IEnumerable`1 page)
   at Unify.Framework.Visitor.ThreadsafeVisitorEvaluator`1.ThreadsafeItemEvaluator.Evaluate()
ClientConnectionId:abc9d8a7-32a0-402b-9273-7c87fc4223c4
Error Number:40197,State:3,Class:20",Normal
20151023,04:21:08,UNIFY Identity Broker,Connector Processor,Information,"Connector Processing started.
Connector Processing started for connector chris21 - POS Form (page 16)",Normal
20151023,04:21:08,UNIFY Identity Broker,List,Information,Next chunk is [1000] sub total [20000]. Duration: 00:00:10.5594588,Normal
20151023,04:21:17,UNIFY Identity Broker,List,Information,Next chunk is [1000] sub total [21000]. Duration: 00:00:08.7187876,Normal
20151023,04:21:23,UNIFY Identity Broker,Change detection engine,Error,"Change detection engine import all items failed.
Change detection engine import all items for connector chris21 - POS Form failed with reason An error occurred while evaluating a task on a worker thread.  See the inner exception details for information.. Duration: 00:06:12.2925941
Error details:
Unify.Framework.EvaluatorVisitorException: An error occurred while evaluating a task on a worker thread.  See the inner exception details for information. ---> System.Data.SqlClient.SqlException: The service has encountered an error processing your request. Please try again. Error code 40174.
A severe error occurred on the current command.  The results, if any, should be discarded.
   at System.Data.SqlClient.SqlConnection.OnError(SqlException exception, Boolean breakConnection, Action`1 wrapCloseInAction)
   at System.Data.SqlClient.TdsParser.ThrowExceptionAndWarning(TdsParserStateObject stateObj, Boolean callerHasConnectionLock, Boolean asyncClose)
   at System.Data.SqlClient.TdsParser.TryRun(RunBehavior runBehavior, SqlCommand cmdHandler, SqlDataReader dataStream, BulkCopySimpleResultSet bulkCopyHandler, TdsParserStateObject stateObj, Boolean& dataReady)
   at System.Data.SqlClient.SqlDataReader.TryHasMoreRows(Boolean& moreRows)
   at System.Data.SqlClient.SqlDataReader.TryReadInternal(Boolean setTimeout, Boolean& more)
   at System.Data.SqlClient.SqlDataReader.Read()
   at System.Data.Linq.SqlClient.ObjectReaderCompiler.ObjectReaderBase`1.Read()
   at System.Data.Linq.SqlClient.ObjectReaderCompiler.ObjectReader`2.MoveNext()
   at System.Linq.Enumerable.WhereSelectEnumerableIterator`2.MoveNext()
   at System.Linq.Buffer`1..ctor(IEnumerable`1 source)
   at System.Linq.Enumerable.ToArray[TSource](IEnumerable`1 source)
   at Unify.Framework.Data.LinqWhereQuery`5.GetEnumerator()
  at System.Linq.Buffer`1..ctor(IEnumerable`1 source)
   at System.Linq.Enumerable.ToArray[TSource](IEnumerable`1 source)
   at Unify.Product.IdentityBroker.EntityRepositoryExtensions.ConvertConnectorEntitiesWithRepositoryEntities(IEnumerable`1 connectorEntities, IMultiKey`1 schemaKey, IQueryable`1 sourceEntities, Guid connectorId, IEnumerable`1 originalEntities)
   at Unify.Product.IdentityBroker.RepositoryChangeDetectionWorkerBase.PerformChangeDetectionOnConnectorEntityPage(IEnumerable`1 connectorEntities, Int32& index, Int32 entitiesProcessedSoFar, IEntityChangesReportGenerator`2 reportGenerator)
   at Unify.Product.IdentityBroker.RepositoryChangeDetectionWorkerBase.<>c__DisplayClass3.<PerformChangeDetection>b__0(IEnumerable`1 page)
   at Unify.Framework.Visitor.ThreadsafeVisitorEvaluator`1.ThreadsafeItemEvaluator.Evaluate()
   --- End of inner exception stack trace ---
   at Unify.Framework.Visitor.ThreadsafeVisitorEvaluator`1.CheckForException()
   at Unify.Framework.Visitor.ThreadsafeVisitorEvaluator`1.WaitForAvailableThread()
   at Unify.Framework.Visitor.ThreadsafeVisitorEvaluator`1.Visit()
   at Unify.Product.IdentityBroker.RepositoryChangeDetectionWorkerBase.PerformChangeDetection(IEnumerable`1 connectorEntities)
   at Unify.Product.IdentityBroker.ChangeDetectionImportAllJob.ImportAllChangeProcess()
   at Unify.Product.IdentityBroker.ChangeDetectionImportAllJob.RunBase()
   at Unify.Framework.DefinedScopeJobAuditTrailJobDecorator.Run()
   at Unify.Product.IdentityBroker.ConnectorJobExecutor.<>c__DisplayClass29.<Run>b__27()
   at Unify.Framework.AsynchronousJobExecutor.PerformJobCallback(Object state)",Normal
20151023,04:21:34,UNIFY Identity Broker,Connector Processor,Information,"Connector processing success.
17625 entites in cumulative total. Current processing of page 16 for connector chris21 - POS Form processed 1175 entities, finding 1175 differences. Duration: 00:00:26.1862477. ",Normal
20151023,04:21:35,UNIFY Identity Broker,Change detection engine,Information,"Started processing changes register items.
Started processing changes register items for connector chris21 - POS Form.",Normal
20151023,04:21:37,UNIFY Identity Broker,Change detection engine,Information,"Changes register item processing completed.
Changes register item processing on connector chris21 - POS Form completed.  Duration: 00:00:02.0317620",Normal