Allow LogMergePolicy to merge more than mergeFactor segments together when the merge is below the min merge size.
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…ther when the merge is below the min merge size. This is essentially porting apache#266 to `LogMergePolicy`. By allowing more than `mergeFactor` segments to be merged together for small merges, the merge policy gets a lower write amplification and indexes have fewer small segments.
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@original-brownbear I remember you looked at indexes that had more segments (and more small segments in particular) than you would have liked, so you may be interested in this. |
original-brownbear
approved these changes
Jan 24, 2025
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I don't have massive experience with the performance impact of merging more segments but seeing how all of this involves tiny segments only anyway + code looks good => LGTM, thanks! Looking at the problematic segments I've observed here and there, this seems like it should prevent a good chunk of those :)
jpountz
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allow_more_than_merge_factor_segments_to_be_merged
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This is essentially porting #266 to
LogMergePolicy. By allowing more thanmergeFactorsegments to be merged together for small merges, the merge policy gets a lower write amplification and indexes have fewer small segments.