Help with slow response/exceptions on new install

Greetings,

  We recently updated a sever that was previously running Web-CAT. The new server is configured as follows (reported by the Tomcat manager):

Tomcat VersionJVM VersionJVM VendorOS NameOS VersionOS ArchitectureHostnameIP AddressApache Tomcat/7.0.68 (Ubuntu)1.8.0_91-8u91-b14-3ubuntu1~16.04.1-b14Oracle CorporationLinux4.4.0-34-genericamd64pi127.0.1.1

The Perl version is 5.22.

We next performed the installation of Web-CAT through the Tomcat management interface. It seemed to hang periodically, but it was ultimately successful. This new installation was able to access/use the previous database tables in MySQL. Following this, we attempted to create a new semester and courses, then add existing assignments. All this seemed to work, but we noticed significant latency on some operations. Finally, we attempted to upload a submission to check the testing. There was a very long delay (>5 miutes) following confirmation of the submission. In the end, this operation generated a WebObjects Error page that listed a NSForwardException [java.lang.StackOverflowError]. I noticed in the call stack that this collection of calls repeats dozens of times before failure:

 

EODatabaseContext.java4660_globalIDForObjectcom.webobjects.eoaccessEODatabaseContext.java4767databaseOperationForObjectcom.webobjects.eoaccessEODatabaseContext.java6535valuesForKeyscom.webobjects.eoaccessEOObjectStoreCoordinator.java326valuesForKeyscom.webobjects.eocontrolEOQualifierSQLGeneration.java439schemaBasedQualifierWithRootEntitycom.webobjects.eoaccessERXExtensions.java316schemaBasedQualifierWithRootEntityer.extensionsEOQualifierSQLGeneration.java179_schemaBasedQualifierWithRootEntitycom.webobjects.eoaccessEODatabaseChannel.java227selectObjectsWithFetchSpecificationcom.webobjects.eoaccessEODatabaseContext.java3055_objectsWithFetchSpecificationEditingContextcom.webobjects.eoaccessEODatabaseContext.java3195objectsWithFetchSpecificationcom.webobjects.eoaccessEOObjectStoreCoordinator.java488objectsWithFetchSpecificationcom.webobjects.eocontrolEOEditingContext.java4069objectsWithFetchSpecificationcom.webobjects.eocontrolERXEC.java1114objectsWithFetchSpecificationer.extensions.eofEODatabaseContext.java4084objectsForSourceGlobalIDcom.webobjects.eoaccessEOObjectStoreCoordinator.java634objectsForSourceGlobalIDcom.webobjects.eocontrolEOEditingContext.java3923objectsForSourceGlobalIDcom.webobjects.eocontrolERXEC.java1070objectsForSourceGlobalIDer.extensions.eofEODatabaseContext.java4245_fireArrayFaultcom.webobjects.eoaccessEOAccessArrayFaultHandler.java77completeInitializationOfObjectcom.webobjects.eoaccess_EOCheapCopyMutableArray.java45willReadcom.webobjects.eocontrol_EOCheapCopyMutableArray.java103countcom.webobjects.eocontrolAssignment.java103userPresentableDescriptionorg.webcat.grader_Assignment.java1560toStringorg.webcat.graderString.java2994valueOfjava.langStringBuilder.java131appendjava.lang

 

I would appreciate some advice about how to begin troubleshotting these problems. Interaction with the Tomcat management interface is reasonably responsive. It is the latency and exceptions encountered through Web-CAT that are unusal.

Thank you,

~James

 

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