How To Fix DB6547 - Der CHNGPGS_THRESH parameter value is within the valid range

SAP Error Message - Details

• Message type: E = Error

• Message class: DB6 - DB6: Alert Monitoring and Alert Configuration

• Message number: 547

• Message text: Der CHNGPGS_THRESH parameter value is within the valid range

Copy of 1st and 2nd blocks of DB6 546

What causes this issue?

By setting this database configuration parameter (CHNGPGS_THRESH), you
determine at what number of changed pages in the buffer pool should
these be written asynchronously to the database. This is done by the
Page Cleaner.

System Response

If you set too high a value for the parameter, it may be that pages are
not written to the database on time. These pages are then written
(before they are replaced because of lack of space) synchronously; that
is, the application must wait until the page that is to be replaced has
been written.
On the other hand, if too low a value is set for the parameter, the
system will write pages to the database unnecessarily often.
You can find more information about this topic in the messages for the
<DS:NA.DB6152>Page Cleaner</>.

Error message extract from SAP system. Copyright SAP SE.

Smart SAP Assistant

• What is the cause and solution for SAP error message DB6547 - Der CHNGPGS_THRESH parameter value is within the valid range ?

  The SAP error message DB6547 indicates that the parameter CHNGPGS_THRESH is set to a value that is within the valid range, but it may not be optimal for your system's performance. This parameter is related to the database's page change threshold, which can affect how the database manages memory and handles page changes.
  Cause:
  The CHNGPGS_THRESH parameter is used to define the threshold for the number of changed pages that can be tolerated before a checkpoint is triggered. If the value is set too low, it can lead to frequent checkpoints, which may degrade performance. Conversely, if it is set too high, it can lead to excessive memory usage and potential performance issues during recovery.
  Solution:
  
  
  Review Current Settings: Check the current value of the CHNGPGS_THRESH parameter. You can do this by using the database administration tools or SQL commands, depending on your database system (e.g., Oracle, SQL Server, etc.).
  
  
  Analyze Performance: Monitor the performance of your SAP system and database. Look for signs of frequent checkpoints or high memory usage. Use performance monitoring tools to gather data on page changes and checkpoint frequency.
  
  
  Adjust Parameter Value: Based on your analysis, consider adjusting the CHNGPGS_THRESH parameter. The optimal value can vary based on your specific workload and system configuration. It may require some experimentation to find the best setting.
  
  
  Consult Documentation: Refer to the official SAP and database documentation for guidelines on recommended values for the CHNGPGS_THRESH parameter based on your database version and workload.
  
  
  Test Changes: After making adjustments, monitor the system's performance to ensure that the changes have a positive effect. Be prepared to revert to the original settings if necessary.
  
  
  Engage with SAP Support: If you are unsure about the appropriate value or if the issue persists, consider reaching out to SAP support for assistance. They can provide guidance based on your specific environment and requirements.
  
  
  Related Information:
  
  Database Documentation: Check the documentation for your specific database (e.g., Oracle, HANA, SQL Server) for detailed information on the CHNGPGS_THRESH parameter and its implications.
  SAP Notes: Look for relevant SAP Notes that may address this error or provide additional context on performance tuning for your specific SAP version.
  Performance Tuning Guides: Review performance tuning guides for SAP systems to understand best practices for managing database parameters and optimizing performance.
  
  By following these steps, you should be able to address the DB6547 error and optimize the CHNGPGS_THRESH parameter for your SAP system.