Archive for November 9th, 2014

Trace Analysis Patterns (Part 93)

Sunday, November 9th, 2014

Sometimes we have several use case instances traced in one log file. Messages and Activity Regions from many Use Case Trails intermingle and make analysis difficult especially with the absence of UCID (Use Case ID), any other identification tags, or Message Links. However, initially most of the time we are interested in a sequence of Significant Events. After finding Anchor Messages we can use Time Deltas to differentiate between trace statements from different Use Case Trails. Here we assume correct Event Sequence Order. We call this pattern Event Sequence Phase by analogy with wave phases (all such individual “waves” may have different “shapes” due to various delays between different stages of their use case and implementation narratives):

In the picture above we also identified Dominant Event Sequence for use case instance C.

- Dmitry Vostokov @ DumpAnalysis.org + TraceAnalysis.org -

Trace Analysis Patterns (Part 92)

Sunday, November 9th, 2014

Use cases are implemented in various components such as subsystems, processes, modules, and source code files. Most of the time with good tracing implementation we are able to see Use Case Trails: log messages corresponding to use case scenarios. For simple systems one log may fully correspond to just one use case, but for complex systems, especially distributed client-server ones, there may be several use case instances present simultaneously in one log. One way to disentangle them in the absence of UCID (Use Case ID) or some other grouping tag is to use Event Sequence Phase, the subject of the next pattern.

Master Traces may also correspond to use cases but they should ideally correspond to only one use case instance.

- Dmitry Vostokov @ DumpAnalysis.org + TraceAnalysis.org -