Cognos performance tuning

Over time, you may experience an increased user population and increased processing requests. Other aspects of your infrastructure may also see increased demand. These changes can affect Cognos Analytics performance and it is important to monitor and tune your deployment regularly.

By tuning the configuration of your Cognos Analytics deployment, you can optimize the speed and efficiency of your Cognos Analytics software and the reports offered in Workforce Management. Infor has found through experience that the following settings can have an impact on your system performance. However, IBM documentation is still the best resource for information on tuning your Cognos Analytics software.

To tune performance for Cognos, you must update reportService.xml, which is located under the <cognosroot>/webapps/p2pd/WEB-INF/services folder.

Adjusting these four parameters can improve Cognos performance and resolve performance issues:

queue_time_limit_ms
Specifies a timeout limit for queues on the Cognos server. The default is 30 seconds. You can specify a higher timeout limit to give the query server enough time to process high concurrency requests (for example, sending 16K query requests to the Cognos server at the same time).
Default: 30000 ms (30 seconds)
Recommended: 120000 ms (120 seconds)
idleTimeLimitSec
Specifies how often to check for idle BIBusTKServerMain processes. The default is 15 minutes. Decrease this value to check for idle processes sooner.
Note: You may need to increase this value to a longer period if the first report of the day takes longer to execute, while the following reports seem to run much more efficiently. The likely cause of this behavior is that BIBusTKServerMain.exe is not initialized; the process takes time to initialize when there is no activity (report server process). Two processes are needed for interactive reporting.
Default: 900 seconds (15 minutes)
Recommended: 300 seconds (5 minutes)
linger_process
Specifies the minimum number of processes to keep in memory once they are started. The default is 1. Changing this value to 0 forces Cognos to recycle BIBusTKServerMain processes more frequently.
Default: 1
Recommended: 0
async_wait_timeout_ms
Specifies the asynchronous timeout. The default is 60 seconds. If you have a high user load (over 165 users) and interactive reports are running continuously in a distributed installation, you may want to increase the asynchronous timeout setting to avoid getting error messages.

Reports that run for more than 7 seconds enter an "asynchronous communication" mode. In this mode, the session sends periodic "wait()" requests to retrieve the data. If this request is not received for over 60 seconds (the default asynchronous timeout) due to delays in the architecture, the dispatcher closes the session.

This error is generated when the dispatcher then receives the "wait" request for the closed session. Adjusting the async_wait_timeout_ms setting can resolve the issue.

Default: 60000 ms (60 seconds)
Recommended: 180000 ms (180 seconds)