[9.0] Avoid over collecting in Limit or Lucene Operator (#123296) #123785
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Currently, we rely on signal propagation for early termination. For example, FROM index | LIMIT 10 can be executed by multiple Drivers: several Drivers to read document IDs and extract fields, and the final Driver to select at most 10 rows. In this scenario, each Lucene Driver can independently collect up to 10 rows until the final Driver has enough rows and signals them to stop collecting. In most cases, this model works fine, but when extracting fields from indices in the warm/cold tier, it can impact performance. This change introduces a Limiter used between LimitOperator and LuceneSourceOperator to avoid over-collecting. We will also need a follow-up to ensure that we do not over-collect between multiple stages of query execution.
dnhatn
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:Analytics/ES|QL
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Backports the following commits to 9.0: