
The passport allows the creation of Distributed Statistics Records (DSRs) and of performance traces across component boundaries.
If statistics records are written beyond component boundaries, the passport is sent together with the communication between the components. Among other things, it contains a GUID that is generated with a new Logical Unit of Work (LUW) and which is used when calling other components within the LUW. By evaluating the DSRs globally, you can collect and analyze all of the data for a LUW. The passport contains a trace flag with which performance trace information can be written for every component involved in a LUW for exactly this LUW.
The passport corresponds to the certificate subrecord (cert subrecord) of the DSR and contains the following fields:
These fields are only filled when the passport is created. All subsequent components leave these fields unchanged.
The ID of the previous system or previous component is always filled with a system or component's own ID before the passport is sent. This means that the direct predecessor can be identified when the passport is received.
The figure below shows how the passport is forwarded and linked to the relevant statistics records: