These settings are available in system.settings and are autogenerated from the ClickHouse snapshot.
min_joined_block_size_bytes
Minimum block size in bytes for JOIN input and output blocks (if join algorithm supports it). Small blocks will be squashed. 0 means unlimited.
min_joined_block_size_rows
Minimum block size in rows for JOIN input and output blocks (if join algorithm supports it). Small blocks will be squashed. 0 means unlimited.