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Showing posts from May, 2012

Measuring application response time using the Scenario instrumentation library.

This blog post describes the Scenario instrumentation library, a simple but useful tool for generating response time measurements from inside a Windows application. The Scenario instrumentation library uses QPC() and QTCT(), the Windows APIs discussed in an earlier blog entry, to gather elapsed times and CPU times between two explicit application-designated code markers. The application response time measurements are then written as ETW events that you can readily gather and analyze.  You can download a copy of the Scenario instrumentation library here at The Scenario class library was originally conceived as a .NET Framework-flavored version of the Application Response Measurement (ARM) standard, which was accepted and sponsored by the Open Group. The idea behind ARM was that adding application response time measurements to an application in a standardized way would promote 3rd party tool development. This was moderately successful for a spel…