How To Fix SDBALM185 - Low hit rate for history/undo data in the data cache (&1&3 < &2&3)

SAP Error Message - Details

• Message type: E = Error

• Message class: SDBALM - SAP DB and liveCache Alert Monitoring

• Message number: 185

• Message text: Low hit rate for history/undo data in the data cache (&1&3 < &2&3)

Self-Explanatory Message

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• What is the cause and solution for SAP error message SDBALM185 - Low hit rate for history/undo data in the data cache (&1&3 < &2&3) ?

  The SAP error message SDBALM185 indicates that there is a low hit rate for history or undo data in the data cache. This can lead to performance issues, as the system is not efficiently retrieving data from the cache, resulting in more frequent database accesses.
  Cause:
  The low hit rate for history/undo data in the data cache can be caused by several factors, including:
  
  Insufficient Cache Size: The data cache may not be large enough to hold the required amount of history or undo data, leading to frequent cache misses.
  High Volume of Transactions: A high volume of transactions can lead to rapid turnover of data in the cache, causing older data to be evicted before it can be reused.
  Inefficient Data Access Patterns: If the application is accessing data in a way that does not take advantage of the cache, it can lead to low hit rates.
  Configuration Issues: Incorrect configuration settings for the data cache can also contribute to low hit rates.
  
  Solution:
  To address the low hit rate for history/undo data in the data cache, consider the following solutions:
  
  Increase Cache Size: Review and increase the size of the data cache if possible. This can help accommodate more history and undo data, improving hit rates.
  Optimize Data Access Patterns: Analyze the data access patterns of your applications and optimize them to make better use of the cache. This may involve changing how data is retrieved or processed.
  Monitor and Adjust Configuration: Use transaction codes like ST02 (Tune Summary) to monitor the performance of the buffer and cache. Adjust the configuration settings for the data cache based on the monitoring results.
  Regularly Clear Cache: In some cases, regularly clearing the cache can help improve performance by removing stale data. However, this should be done cautiously, as it can also lead to increased database access.
  Review System Load: If the system is under heavy load, consider scaling up resources or optimizing the workload to reduce the pressure on the cache.
  
  Related Information:
  
  Transaction Codes: Use transaction codes like ST02 (Buffer Monitor) and ST04 (Database Performance Monitor) to analyze cache performance and database access patterns.
  SAP Notes: Check for relevant SAP Notes that may provide additional insights or patches related to this error message.
  Performance Tuning: Consider engaging in performance tuning activities, which may include reviewing SQL queries, optimizing database indexes, and analyzing application performance.
  
  By addressing the underlying causes and implementing the suggested solutions, you can improve the hit rate for history/undo data in the data cache and enhance overall system performance.