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  1. Debezium
  2. DBZ-1078

Optimize sys.fn_cdc_map_lsn_to_time() calls

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      In streaming phase, a sys.fn_cdc_map_lsn_to_time() stored procedure is executed for each row. This might be a performance bottleneck.

      io.debezium.connector.sqlserver.SqlServerStreamingChangeEventSource#offsetContext

      offsetContext.setSourceTime(connection.timestampOfLsn(commitLsn));
      
      • We can take advantage of the fact that the stored procedure is called for commitLsn, which, in general, can be the same for many rows. Even having a simple LRU cache which keeps a few entries we can significantly reduce the number of such queries.
      • Updating sourceTime can be optional (via configuration).

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              • Assignee:
                Unassigned
                Reporter:
                grzegorzk Grzegorz KoĊ‚akowski
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