Typically the real execution flow in the applications based on Intel® Threading Building Blocks (Intel TBB) or OpenMP* is very different from the code flow. During the user-mode sampling and tracing analysis of an Intel TBB-based application or an OpenMP application using Intel runtime libraries, the Intel® VTune™ Amplifier automatically enables the Stitch stacks option to restore a logical call tree by catching notifications from the runtime and attach stacks to a point introducing a parallel workload. To view the OpenMP or Intel TBB objects hierarchy, explore the data provided in the Top-down Tree pane.
Note
To analyze a logically structured OpenMP call flow, make sure to compile and run your code with the Intel® Compiler 13.1 Update 3 or higher (part of the Intel Composer XE 2013 Update 3).
Stack stitching is available when you run the application from the VTune Amplifier (the Launch Application target type). It does not work when attaching to the application (the Attach to Process target type).
To disable stack stitching for your custom user-mode sampling and tracing analysis type, deselect the Stitch stacks option in the Custom Analysis dialog box. In this case, the Top-down Tree pane displays separate entries for OpenMP worker threads.
