Unable to instrument IIS Spydus application (Spydus.exe) running under FastCGI using the APM .NET agent.

Document ID : KB000040123
Last Modified Date : 14/02/2018
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  • The Spydus application (third party library management solution) is hosted by IIS
  • There are multiple Spydus application/agent processes.
  • One Spydus application can be instrumented by the .NET agent but another running under FastCGI cannot i.e. no metrics are visible for that application in the Introscope Investigator.



  • .NET version 4.0 hosted on IIS 7.5
  • APM .NET Agent had installed with version with OOTB configuration



  • The .NET Agent can monitor only those languages that conform to the Common Language Infrastructure (CLI), which compile entirely to the Common Intermediate Language (CIL) bytecode (formerly Microsoft Intermediate Language/MSIL) in order to run under the Common Language Runtime (CLR) e.g. C#.NET, VB.NET
  • The FastCGI implementation of Spydus is written in C++ which does not compile to CIL and thus cannot be instrumented by the .NET agent.