How do Does CLR Profiler work?

In order-to-use-a profiler properly, you need-understand how the data is collected and the limitations of the tool. The CLR Profiler uses a special interface to the runtime this allows it to get callbacks when particular events happen wit Hin the runtime (msdn.microsoft.com/library/ms404511.aspx). Currently, this interface can being used only if the process being profiled are started with certain environment variables set That inform, the runtime regarding the contact mechanism to the profiler. Thus, there is some limitations, such as the inability to the attach process. CLR Profiler must start the process with the right environment variables set. For services that is typically started by the OS directly, like ASP, special procedures has to be followed (see CLR Profiler.doc from the download for details). As an aside, for certain scenarios we had added API support for attach in the. NET Framework 4 (and only the API support; Support for attaching the CLR Profiler toolwould follow soon after).

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How do Does CLR Profiler work?