How to: Launch a Stand-Alone .NET Framework Application with the Profiler to Collect Memory Data by Using the Command Line

This topic describes how to use Visual Studio Profiling Tools command-line tools to start a .NET Framework stand-alone (client) application and collect memory data.

A profiling session has three parts:

• Starting the application by using the profiler.

• Collecting profiling data.

• Ending the profiling session.

Starting the Application with the Profiler

To start a target application by using the profiler, you use the VSPerfCmd.exe/start and /launch options to initialize the profiler and start the application. You can specify /start and /launch and their respective options on one command line.

You can also add the /globaloff options to pause data collection at the start of the target application. You then use /globalon to start to collect data.

To start an application by using the Profiler

1. Open a Command Prompt window.

2. Start the profiler. Type:

   **VSPerfCmd /start:sample /output:**OutputFile [Options]

   • The /start:sample option initializes the profiler.

   • The /output**:**OutputFile option is required with /start. OutputFile specifies the name and location of the profiling data (.vsp) file.

   You can use any of the following options with the /start:sample option.

   Option	Description
   /wincounter:WinCounterPath	Specifies a Windows performance counter to be collected during profiling.
   /automark:Interval	Use with /wincounter only. Specifies the number of milliseconds between Windows performance counter collection events. Default is 500 ms.

3. Start the target application. Type:

   VSPerfCmd /launch:appName/gc:{allocation|lifetime}[Options]

   • The /gc**:**Keyword option is required to collect .NET Framework memory data. The keyword parameter specifies whether to collect memory allocation data, or to collect both memory allocation and object lifetime data.

     Keyword	Description
     allocation	Collect memory allocation data only.
     lifetime	Collect both memory allocation and object lifetime data.

   You can use any of the following options with the /launch option.

   Option	Description
   /args:Arguments	Specifies a string that contains the command-line arguments to be passed to the target application.
   /console	Starts the target command-line application in a separate window.
   /events:Config	Specifies an Event Tracing for Windows (ETW) event to be collected during profiling. ETW events are collected in a separate (.etl) file.
   /targetclr:Version	Specifies the version of the common language runtime (CLR) to profile when more than one version of the runtime is loaded in an application.

Controlling Data Collection

When the target application is running, you can control data collection by starting and stopping the writing of data to the file by using VSPerfCmd.exe options. Controlling data collection enables you to collect data for a specific part of program execution, such as starting or shutting down the application.

To start and stop data collection

• The following pairs of options start and stop data collection. Specify each option on a separate command line. You can turn data collection on and off multiple times.

  Option	Description
  /globalon /globaloff	Starts (/globalon) or stops (/globaloff) data collection for all processes.
  /processon:PIDprocessoff:PID	Starts (/processon) or stops (/processoff) data collection for the process that is specified by the process ID (PID).
  /attach:PID/detach	/attach starts to collect data for the process that is specified by PID (the process ID). /detach stops data collection for all processes.

• You can also use the VSPerfCmd.exe/mark option to insert a profiling mark into the data file. The /mark command adds an identifier, a time stamp, and an optional user-defined text string. Marks can be used to filter the data.

Ending the Profiling Session

To end a profiling session, the profiler must be detached from all profiled processes and the profiler must be explicitly shut down. You can detach the profiler from an application that was profiled by using the sampling method by closing the application or by calling the VSPerfCmd /detach option. You then call the VSPerfCmd /shutdown option to turn off the profiler and close the profiling data file. The VSPerfClrEnv /off command clears the profiling environment variables.

To end a profiling session

1. Perform one of the following steps to detach the profiler from the target application:

   • Close the target application.

     -or-

   • Type VSPerfCmd /detach

2. Shut down the profiler. Type:

   VSPerfCmd /shutdown

See Also

Concepts

Command-Line Profiling of Stand-Alone Applications

Other Resources

Profiling Tools .NET Memory Data Views