SAP Datasphere Analytical Model Performance Trace & PlanViz

[christian_willi]

Hi,

I want to analyze the Performance of an Analytical Model in SAP Datasphere to identify possible design issues. Therefore I follow the SAP Help documentation to extract the MDS Statement and generate the PlanViz File.

But I currently have the following problem:

1. I execute the Model in SAC and retreive the MDS statement. Here I have a runtime of about ~40 seconds.
2. Then I call generate the MDS statement with the CALL SYS.EXECUTE_MDS(...) statement. Here I have the behaviour that this is then generated in around ~1 second and the PlanViz is not reflecting the ~40 seconds runtime in the frontend.

My current assumption is that this is due to the MDS cache. But in the Database Console also cannot flush it, due to missing authorization. 

Does anybody has had similar issues or knows any best practices to generate a correct PlanViz out of an Analytical Model MDS statement?

Thank you for your input!

Regards

Christian

[Martin_Kuma]

Hi Christian. it can indeed be that the SAC, or Browser take the time, not DSP. 

first check the menu->Perf. Optimization - Analyze story Perf. Check scripts, widgets, ... DB Calls 

you can also check the SAC statistics / Admin content --> there you will see where the time gets lost if SAC or Browser. 

I have observed in heavy stories that only a fraction of time was used in DSP, rest was SAC and about 50% was Browser. 

Martin

[christian_willi]

Hi Martin,

I agree SAC also can be a main driver in performance. For my use case I narrowed it down to a simple test story with just one table. However, I think the PlanViz would give some meaningful insights.

Thanks

Christian

[Martin_Kuma]

Hi Christian, I have created PlanViz only in DSP :(, sorry. But if you have an issue with a simple story (no scripting, no buttons, filters, ic, ...) with one table, what happens when you preview the data in AM, how fast is that (maybe persistency of the model-view would help)? If you have done that already and AM is fast, then connection. Because a simple story with one table cannot take that much time. Or maybe there is no limit on the table self - so no 'too many entries' will stop the loading. 

[christian_willi]

Hi Martin,
currently I am now creating individual PlanViz files for the single views which are executed and go from there to analyze and improve performance. But I think it would be benficial to come with a specific user selection from the frontend and get insights what is executed and how. Then you would also get a feeling how much memory is needed to execute a user execution. 
Yes persisting is also something we are already considering.