How To Fix HH044 - Database buffer read quality could be better (buffers too small?)

SAP Error Message - Details

• Message type: E = Error

• Message class: HH - (Long) text for check tool 'infcfgcheck'

• Message number: 044

• Message text: Database buffer read quality could be better (buffers too small?)

What causes this issue?

This is a single 'performance' check and therefore does not
describe a critical system status. It is neither necessary nor
time-critical to perform the steps described below, but they could
help improve the overall performance of your R/3 System.

The system issues an error message and will not allow you to continue with this transaction until the error is resolved.

The 'hit rate' of pages in the database buffer in percent is not
optimal
for read accesses. A rate of at least 95% is considered to be
optimal. A better 'hit rate' can often be obtained by extending
the database buffer (thus reducing the 'displacement rate' of pages in
the buffer). On the other hand, the ONCONFIG parameter 'BUFFERS' should
not be increased if this is not necessary in order to keep the
use of Shared Memory (i.e. main memory) within reason.

System Response

How to fix this error?

Check the read quality of the database buffer regularly with
'onstat -p'. If the percent value is constantly below 95%, try
increasing the ONCONFIG paramter 'BUFFERS'. You can assume 20% of the
physical memory as a approximate value for the buffer size.
As user 'informix', edit file
'$INFORMIXDIR/etc/$ONCONFIG' ('BUFFERS' = number of pages).
CAUTION: The change will only become active when the database has
been started up.
Please also refer to Note 38307.

Error message extract from SAP system. Copyright SAP SE.

Smart SAP Assistant

• What is the cause and solution for SAP error message HH044 - Database buffer read quality could be better (buffers too small?) ?

  The SAP error message HH044, which states "Database buffer read quality could be better (buffers too small?)", indicates that the performance of the database buffer is not optimal. This can lead to inefficiencies in data retrieval and overall system performance. Here’s a breakdown of the cause, potential solutions, and related information:
  Cause:
  
  Insufficient Buffer Size: The database buffer may be too small to hold the frequently accessed data, leading to increased disk I/O operations.
  High Data Volume: If the volume of data being processed exceeds the capacity of the buffer, it can lead to performance degradation.
  Inefficient Buffer Management: Poorly configured buffer management settings can also contribute to this issue.
  Increased Workload: A sudden increase in workload or user activity can strain the existing buffer settings.
  
  Solution:
  
  
  Increase Buffer Size:
  
  Review and adjust the size of the database buffer. This can typically be done in the database configuration settings.
  For SAP systems, you can adjust the parameters in the instance profile (e.g., dbs/db_buffer for the database buffer size).
  
  
  
  Monitor Buffer Usage:
  
  Use transaction codes like ST02 (Tune Summary) to monitor the buffer usage and identify if the buffer is indeed a bottleneck.
  Analyze the buffer hit ratio to determine how often data is being read from the buffer versus the disk.
  
  
  
  Optimize Database Configuration:
  
  Ensure that the database parameters are optimized for your specific workload and data access patterns.
  Consult the database documentation for best practices on buffer management.
  
  
  
  Regular Maintenance:
  
  Perform regular database maintenance tasks such as reorganization and indexing to improve performance.
  Ensure that statistics are up to date, as this can help the database optimizer make better decisions.
  
  
  
  Consider Hardware Upgrades:
  
  If the workload has significantly increased, consider upgrading the hardware resources (CPU, RAM, Disk I/O) to better handle the load.
  
  
  
  Consult SAP Notes:
  
  Check for any relevant SAP Notes that may provide additional guidance or patches related to buffer management and performance tuning.
  
  
  
  Related Information:
  
  
  Transaction Codes: 
  
  ST02: Tune Summary for monitoring buffer performance.
  ST04: Database Performance Monitor for deeper insights into database performance.
  
  
  
  SAP Basis Administration: Understanding the role of SAP Basis in managing system performance and database configurations is crucial.
  
  
  Documentation: Refer to the official SAP documentation for your specific database (e.g., Oracle, HANA, SQL Server) for detailed configuration settings and performance tuning guidelines.
  
  
  Performance Monitoring Tools: Consider using SAP Solution Manager or other performance monitoring tools to get a comprehensive view of system performance.
  
  
  By addressing the underlying causes and implementing the suggested solutions, you can improve the database buffer read quality and enhance overall system performance.