Hi Experts
We are facing the below issues with our tabular model and I'm monitoring the Profiler, but couldn't able to answer below
Some Facts
- Memory shoots during Query Execution
- Query Times-out Very Often
- RAM size is 14 times bigger than Model Size. Nothing else is in server except tabular model.
Actions Performed and Results
- Applied Cumulative Hotfix 2 and it resolved 1 partially. At-least memory is released as we had NESTED IFs in calculation.
- Tried to remove calculated measures in DAX query calls, but no significant increase in performance and Timing out
- In the process of analyzing profile and could see the SQLs using events VERTIPAQ Query Begin and End, which helped to find some optimization strategy
- Server side Vertipaq Paging property is 0. We don't want paging.
Asks
Regardless of the actions performed, we have below queries
1. Profiler -> What is the meaning of SET DC_KIND ="AUTO", SET DC_KIND="C64" etc. It comes before every VERTIPAQ SQL text
2. Profiler -> In a single DAX state, the same VERTIPAQ SQL runs multiple times for different reasons (understandably), but it has different DC_KIND values. The Duration is different though with many in AUTO is 0. Ensure that the Query doesn't use DATACACHE.
3. Memory Utilization -> What operations consume memory? SUMMARIZE/SUM etc?. Is it that anything that returns a inner table requires temp table to be created in memory? How to find the temp table creation using Profiler Event.
4. Memory Utilization -> Will the temp tables created are reused across sessions? Is it that session cache based on Security group?
5. General -> Even though the calculated measures are removed from DAX queries having only the direct attributes, the query doesn't give great performance. Anything specific to look out?
Thanks for clarifications/guidance.
Regards
kart
kart