This is a re-visit of an already closed ticket, SERVER-21887.
- duplicates
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SERVER-23408 Use a smarter batch size for small samples
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 - Closed
 
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- is duplicated by
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SERVER-24710 Optimize $sample+$project
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 - Closed
 
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- related to
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SERVER-21887 $sample takes disproportionately long time on newly created collection
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 - Closed
 
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- links to