Baselining performance

[Tim86]

Anyone have good suggestions for measuring performance of Cognos?  Here's my challenge:  we often get emails from users with vague comments like "Cognos seems slow today" or "my reports are taking longer than usual today".  So I spend time investigating, without knowing for certain if there is even an issue at all.  One idea I had was to create some basic benchmarking reports, that I could run and get a timing, which I could compare to some baseline timings.  Does anyone else do this, or something similar, to determine when you are truly having performance issues?  Please describe what you do, and how well it works for you.  Also, any suggestions for distinguishing performance issues with the database versus the Cognos application?

[dcsoke]

How's your server architecture setup, single install or distributed and what software is installed on each? Is it tuned appropriately according to Cognos guidelines?

"Performance" issues are difficult to pinpoint and there are no std benchmarking reports. Your server admin should be able to log the cpu usage and available memory to determine when there are spikes and how bad it actually is.

[Rahul Ganguli]

Hi,

Do you want to measure performance of your Cognos Engine? In that case you can install the samples and note the timings for samples, since the database for samples didn't changes at all you can treat this as benchmark reports.

But, if you want it for your complete BI solution, which includes the Data Warehouse also, It would be less accurate since the Database size may change, there may be something processed at cognos side which you wanted to push to DB. For this kind of performance measurement you should track performance of individual components separately.

Regards,
Rahul

[kommireddy]

Majority of performance bottlenecks are due to inefficient query performance on DB side, unless there's heavy formatting involved. If you are reporting DB fact tables gets refreshed every day through ETL process, make sure stats are updated periodically. You can capture SQL generated by your standard reports and run them directly against reporting DB to get baseline performance numbers. Apart from DB bottlenecks, network issues could also cause cognos reports run slower. Involve Network team in investigation and make sure packet sizes are acceptable between cognos application servers and DB server. One more thing to consider is number of concurrent users on system, make sure your architecture is sized to handle required concurrent users. You can install multiple dispatchers on single server to improve the performance and each dispatcher JVM is limited to use 2GB memory. I hope it helps.