The .NET Perfmon Collector agent is showing a gradual increase in the historical metric count which if unchecked will eventually cause the agent to be clamped on the Enterprise Manager
Identified via metric count tab in the investigator using a 30 day view that the growing number of dynamic metrics were being collected under Perfmon|.NET Data Provider for SQL Server.
This was defined in the agent profile query property introscope.agent.perfmon.metric.filterPattern
This was modified and teh following string removed |.NET Data Provider*|*|* from the query
That metric branch stopped reporting after perfmon restart