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Monitor Reference System

You can monitor the reference-system to find out more about the runtime behavior of your application. The reference-system ensures that each object has only one in memory representation.

Configure the Reference System Monitoring Support

First you need to add the monitoring support to the db4o configuration.

configuration.Common.Add(new ReferenceSystemMonitoringSupport());
ReferenceSystemMonitoring.cs: Add reference system monitoring
configuration.Common.Add(New ReferenceSystemMonitoringSupport())
ReferenceSystemMonitoring.vb: Add reference system monitoring

The Freespace Statistics

number of object references: Tells you how many references are currently hold in the reference-system. By default db4o uses weak references to objects. If this count is very high, you might hold unnecessary references to persisted objects in your application.