Characteristics of FastCAP and CallCAP Probes

Other versions of this page are also available for the following:

Windows Mobile Not Supported Windows Embedded CE Supported

8/27/2008

Call Profiler supports FastCAP and CallCAP probes as a means of instrumenting your code:

You insert a FastCAP probe immediately before each function call and immediately after each function return.
You insert a CallCAP probe immediately after each function call and immediately before each function return.

Note

FastCAP instrumentation is not supported on x86 microprocessors.

FastCAP Probes

FastCAP probes exhibit the following characteristics:

They do not capture the entry call from a noninstrumented module to an instrumented module.
They do not capture a call or callback from a function pointer.
They capture a call to a noninstrumented module.
FastCAP instrumentation can result in a large instrumented executable because probes are inserted at every instance of a profiled function.

CallCAP probes exhibit the following characteristics:

They capture the entry call from a noninstrumented module to an instrumented module.
They do not capture a call to a noninstrumented module.
If a function call requires the data for the function to be paged in from disk, CallCAP probes attribute the time taken for the associated page fault to the function making the call.
CallCAP instrumentation has a minimal effect on the size of the instrumented executable because CallCAP probes are inserted only in the function definition.