Message type: E = Error
Message class:  RSO_CTC - Message class for CTC related messages 
Message number: 221
Message text: Source system &2: delta queue contains large data quantity (&1 blocks)
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The SAP error message RSO_CTC221 indicates that the delta queue for a source system contains a large quantity of data, which can lead to performance issues or delays in data extraction. This error typically occurs in the context of SAP BW (Business Warehouse) when dealing with data extraction from SAP source systems, particularly when using the delta mechanism.
Cause: Large Volume of Delta Data: The delta queue has accumulated a significant amount of data that has not yet been processed. This can happen if the data extraction process is not running frequently enough or if there are issues with the data transfer. Long Running Extractors: If the data extraction process is taking too long to complete, it can lead to a backlog in the delta queue. System Performance Issues: Performance issues in the source system or the BW system can also contribute to the accumulation of data in the delta queue.
Configuration Issues: Incorrect configuration
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