Dynamic properties feature in IIS7 configurtion system lets you expose dynamic data as configuration system properties. RscaExt.xml which is part of IIS7 has all the RSCA (runtime status and control APIs) functionality exposed as dynamic properties through configuration system (read more here). One of the things RSCA let you do is expose custom runtime data from a worker process using GetCustomData method. You can call GetCustomData method for a worker process instance which sends a GL_RSCA_QUERY notification to the worker process.