How To Fix CNV_DMC_HC066 - &1 - &2: Average latency (&3) has exceeded error threshold by &4

SAP Error Message - Details

• Message type: E = Error

• Message class: CNV_DMC_HC -

• Message number: 066

• Message text: &1 - &2: Average latency (&3) has exceeded error threshold by &4

What causes this issue?

SAP Landscape Transformation Replication Server calculates the time
between the recording of a change in the source system and sending this
data to the target. The respective threshold has been exceeded.

System Response

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

How to fix this error?

Many different elements influence latency. It is always a good idea with
starting to monitor the latency values over some time. You can view
historical latency information in transaction LTRC. On the tab
<ZK>Expert Functions</>, choose <ZK>Display Replication Statistics</>.
If there are consistently high latency values, there may be issues with
the connections to the source or target systems, or issues within the
operations executed in these systems.
If you see different latency values (maybe aligned your business hours),
it is likely that the amount of changes in the source system is higher
than what SAP Landscape Transformation Replication Server can transfer
with one job. If this is the case, options for improving latency include
filtering the data, or specifying ranges for the logging table (for more
information, see <ZK>Performance Options</> in transaction LTRS).

Procedure for System Administrators

Error message extract from SAP system. Copyright SAP SE.

Smart SAP Assistant

• What is the cause and solution for SAP error message CNV_DMC_HC066 - &1 - &2: Average latency (&3) has exceeded error threshold by &4 ?

  The SAP error message CNV_DMC_HC066 typically relates to data migration processes, particularly in the context of SAP Data Migration Cockpit (DMC) or SAP S/4HANA migrations. This specific error indicates that the average latency of data processing has exceeded a predefined threshold, which can lead to performance issues during the migration process.
  Cause:
  
  
  High Latency: The average latency of data processing is too high, which can be caused by various factors such as:
  
  Network issues causing delays in data transfer.
  Resource contention on the database or application server.
  Inefficient data processing logic or transformations.
  Large volumes of data being processed at once.
  
  
  
  System Performance: The underlying system may not have sufficient resources (CPU, memory, I/O) to handle the data migration workload efficiently.
  
  
  Configuration Issues: Incorrect configuration settings in the migration tools or the underlying database can lead to performance bottlenecks.
  
  
  Solution:
  
  
  Monitor System Performance: Use monitoring tools to check the performance of the database and application servers. Look for CPU, memory, and I/O bottlenecks.
  
  
  Optimize Data Migration:
  
  Break down large data migration jobs into smaller batches to reduce the load on the system.
  Review and optimize the data transformation logic to ensure it is efficient.
  
  
  
  Network Optimization: Ensure that the network connection between the source and target systems is stable and has sufficient bandwidth.
  
  
  Adjust Thresholds: If the high latency is acceptable for your specific use case, consider adjusting the error threshold settings in the migration tool configuration.
  
  
  Check Logs: Review the logs for any additional error messages or warnings that could provide more context on the issue.
  
  
  Consult Documentation: Refer to the SAP documentation for the Data Migration Cockpit for any specific recommendations or best practices related to performance tuning.
  
  
  Engage SAP Support: If the issue persists, consider reaching out to SAP support for further assistance, especially if you suspect a bug or require deeper analysis.
  
  
  Related Information:
  
  SAP Notes: Check for any relevant SAP Notes that might address known issues or provide patches related to the CNV_DMC_HC066 error.
  Performance Tuning Guides: Look for SAP performance tuning guides specific to the version of SAP you are using, as they may provide insights into optimizing data migration processes.
  Community Forums: Engage with the SAP community forums or user groups where similar issues may have been discussed, and solutions shared.
  
  By addressing the underlying causes of the high latency and optimizing the migration process, you should be able to resolve the CNV_DMC_HC066 error and improve the overall performance of your data migration activities.