Improve SortPreservingMerge::enable_round_robin_repartition docs #13826
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alamb
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documentation
alamb
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jayzhan211
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Dec 18, 2024
| /// | ||
| /// When true (the default) equal output rows are placed in the merged | ||
| /// stream when ready, which is faster but not stable (can vary from | ||
| /// run to run). |
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From what I remember, round robin repartition choose the smaller index if other condition is equals (value and polled count is equal). If there are 3 streams, we choose 1, 2, 3 and back to 1, 2, 3 (because we know the polled count) until the value advanced. Do you know why the result vary from run to run and is not always the same?
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Poll may be pending because of networking so value is not yet ready? Better includes the reason in the comment
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Which issue does this PR close?
Rationale for this change
While reviweing #13133 as we integrate it into InfluxDB I reviewed the behavior of
SortPreservingMergeand what it did and wanted to encode my findings in some more docsWhat changes are included in this PR?
Are these changes tested?
by CI,
Are there any user-facing changes?
Only docs, no functional changes