Bump floor segment size to 16MB. #14189
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This bumps the floor segment size from 2MB (`TieredMergePolicy`) / 1.6MB (`LogByteSizeMergePolicy`) to 16MB in Lucene 11. My motivation is that such small segment sizes don't make index structures actually helpful vs. linear scans, so we should avoid them. Furthermore, there has been progress on merging rules for segments below the floor size, in particular merge policies no longer perform quadratic merging (apache#900) so this change will not make indexing/merging absurdly slow if an application flushes tiny segments.
mikemccand
approved these changes
Feb 3, 2025
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Thanks for the feedback, I was hesitating. Let's pull this in 10.2 then. |
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For reference, this is roughly a 10x increase of the floor segment size, so given that |
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This PR has not had activity in the past 2 weeks, labeling it as stale. If the PR is waiting for review, notify the [email protected] list. Thank you for your contribution! |
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This bumps the floor segment size from 2MB (
TieredMergePolicy) / 1.6MB (LogByteSizeMergePolicy) to 16MB in Lucene 11.My motivation is that such small segment sizes don't make index structures actually helpful vs. linear scans, so we should avoid them. Furthermore, there has been progress on merging rules for segments below the floor size, in particular merge policies no longer perform quadratic merging (#900) so this change will not make indexing/merging absurdly slow if an application flushes tiny segments.