Report performance tuning in report studio

If all reports are slow, the issue may be due to your environment or database. If all reports from a specific package are slow, the issue may due to the model design. If just one report is slow, the issue may be due to a specific report element.

1. How many queries does your report contain?
2. The number of queries on the report will proportionally affect the report execution time.
3. Does the report run slowly for everyone, or just for one user?
4. If the report runs slowly for just one user, the issue may be due to something in that user’s environment, such as virus scanning, page file size or location
5. Settings or their location on the network.
6. If many people are running the same report at the same time, you may need to scale your environment or consider using dispatcher routing rules to direct all requests for a specific package or group of users to a specific server or server group. For more information, see the IBM Cognos Business Intelligence Administration and Security Guide.
7. Do your queries require local processing?
8. The following report elements require local processing: crosstabs and charts, master relationships, unions or joins, multiple fact queries, bursting, and non-vendor specific functions. Local processing requires the IBM Cognos server to compute operations on the result set returned by the database, which can impact the SQL execution time.
9. Does your environment use a Custom Authentication Provider?
10. Using a Custom Authentication Provider could cause a memory leak if the code is not destroying objects correctly.
11. Have you reviewed the logs in the c10_location/logs directory and the audit logs?
12. They may help you identify the source of the problem. Monitoring your processes, such as the Java TM and Business Intelligence bus processes could also identify excessive memory use.
13. Is your environment tuned correctly?
14. For more information, see the Performance Tuning Settings for IBM Cognos 8 Business Intelligence and the IBM Cognos 8 Business Intelligence Performance Tuning Cheat Sheet documents available online at www.ibm.com.
15. Have you recently upgraded?
16. Ensure that any tuning settings that were applied to your previous installation are applied to the new environment. Ensure that your models have been verified, upgraded, and republished. Verify that the IBM Cognos Framework Manager governor that allows enhanced model portability at runtime is not enabled. Depending on your upgrade method, you may also need to open and save the reports again after upgrading.
17. Change the order in which items are queried from the database.
18. Create sections without creating master detail relationships.
19. Share queries between lists and crosstab.
20. Convert queries to SQL
21. Avoid using functions with limited support.
22. Be aware of the limitations of creating expressions with SAP BW data sources
23. Use Select & Search prompts instead of value prompts if your list of prompts is long
24. Provide your own prompt values in a prompt to avoid accessing the database.
25. Suppress null cells using filters.
26. Set page breaks without creating master detail relationships
27. Do not modify IBM Cognos Analysis Studio set definitions.
28. Do not put filters on non-identifiers.
29. Avoid combining large hierarchy levels and sets in a drill-through report in a way that creates large
30. Use database functions when possible.