max_bytes_to_merge_at_max_space_in_pool
The maximum total parts size (in bytes) to be merged into one part, if there are enough resources available. Corresponds roughly to the maximum possible part size created by an automatic background merge. (0 means merges will be disabled) Possible values:- Any non-negative integer.
max_bytes_to_merge_at_max_space_in_pool.
Merges initiated by OPTIMIZE FINAL
ignore max_bytes_to_merge_at_max_space_in_pool (only the free disk space
is taken into account).
max_bytes_to_merge_at_min_space_in_pool
The maximum total part size (in bytes) to be merged into one part, with the minimum available resources in the background pool. Possible values:- Any positive integer.
max_bytes_to_merge_at_min_space_in_pool defines the maximum total size of
parts which can be merged despite the lack of available disk space (in pool).
This is necessary to reduce the number of small parts and the chance of
Too many parts errors.
Merges book disk space by doubling the total merged parts sizes.
Thus, with a small amount of free disk space, a situation may occur in which
there is free space, but this space is already booked by ongoing large merges,
so other merges are unable to start, and the number of small parts grows
with every insert.