Archive for the ‘Process Monitor Log Analysis’ Category

Trace Analysis Patterns (Part 72)

Tuesday, May 21st, 2013

Sometimes we look at a trace or log and instead of Error Messages we only see their “signs” such as a DLL load event for an error or fault reporting module or a module that is related to symbol files such diasymreader.dll. We call this pattern Hidden Error by an analogy to Hidden Exception in memory dump analysis pattern catalogue although sometimes we can see such modules in memory dump Module Collection. For example, the presence of diasymreader module may signify an unreported .NET exception and suggest a dump collection strategy.

- Dmitry Vostokov @ + -

Trace Analysis Patterns (Part 64)

Friday, February 15th, 2013

Inter-Correlation analysis between a normal and a problem logs to find a Bifurcation Point (and a possible root cause) becomes a difficult task when both traces come from different environments with widely differing Background Components. Here a new analysis pattern called Sheaf of Activities (borrowed from sheaves from mathematics) can help. Basically this pattern is also a tool in tracking properties of trace message subsets. First we find out important message types around some Activity Region where we hope to find a difference between two traces:

Then we create several Adjoint Threads from different message types, for example, based on operation type or function name:

Then we analyze subtraces separately to find out a bifurcation point in each of them and then use this knowledge to find out differences between the original full traces.

- Dmitry Vostokov @ + -