v.24.10Experimental Feature
Introduced experimental merge selector mode for MergeTree tables
Introduced a special (experimental) mode of a merge selector for MergeTree tables which makes it more aggressive for the partitions that are close to the limit by the number of parts. It is controlled by the merge_selector_use_blurry_base MergeTree-level setting. #70645 (Nikita Mikhaylov).Why it matters
This feature addresses the issue of partitions accumulating too many parts in MergeTree tables, which can degrade performance. By making the merge selector more aggressive for partitions close to the maximum parts limit, it helps maintain optimal table performance and resource usage.How to use it
Enable the feature by setting the MergeTree-level settingmerge_selector_use_blurry_base to 1 (or true) to activate the aggressive merge selector mode.