What is New in NDB Cluster • Disk Data and cluster restarts.   Beginning with NDB 8.0.21, an initial restart of the cluster forces the removal of all Disk Data objects such as tablespaces and log file groups, including any data files and undo log files associated with these objects. • Disk Data extent allocation.   Beginning with NDB 8.0.20, allocation of extents in data files is done in a round-robin fashion among all data files used by a given tablespace. This is expected to improve distribution of data in cases where multiple storage devices are used for Disk Data storage. • --ndb-log-fail-terminate option.   Beginning with NDB 8.0.21, you can cause the SQL node to terminate whenever it is unable to log all row events fully. This can be done by starting  mysqld  with the --ndb-log-fail-terminate  option. • AllowUnresolvedHostNames parameter.   By default, a management node refuses to start when it cannot resolve a host name present in the global configuration file, which can be problematic in some environments such as Kubernetes. Beginning with NDB 8.0.22, it is possible to override this behavior by setting  AllowUnresolvedHostNames  to  true  in the  [tcp default]  section of the cluster global confugration file ( config.ini  file). Doing so causes such errors to be treated as warnings instead, and to permit  ndb_mgmd  to continue starting • Blob write performance enhancements.   NDB 8.0.22 implements a number of improvements which allow more efficient batching when modifying multiple blob columns in the same row, or when modifying multiple rows containing blob columns in the same statement, by reducing the number of round trips required between an SQL or other API node and the data nodes when applying these modifications. The performance of many  INSERT ,  UPDATE , and  DELETE  statements can thus be improved. Examples of such statements are listed here, where  table  is an  NDB  table containing one or more Blob columns: • INSERT INTO  table  VALUES ROW(1,  blob_value1 ,  blob_value2 , ...) , that is, insertion of a row containing one or more Blob columns • INSERT INTO  table  VALUES ROW(1,  blob_value1 ), ROW(2,  blob_value2 ), ROW(3, blob_value3 ), ... , that is, insertion of multiple rows containing one or more Blob columns • UPDATE  table  SET  blob_column1  =  blob_value1 ,  blob_column2  = blob_value2 , ... • UPDATE  table  SET  blob_column  =  blob_value  WHERE  primary_key_column  in ( value_list ) , where the primary key column is not a Blob type • DELETE FROM  table  WHERE  primary_key_column  =  value , where the primary key column is not a Blob type • DELETE FROM  table  WHERE  primary_key_column  IN ( value_list ) , where the primary key column is not a Blob type Other SQL statements may benefit from these improvements as well. These include  LOAD DATA INFILE  and  CREATE TABLE ... SELECT ... . In addition,  ALTER TABLE  table  ENGINE = NDB , where  table  uses a storage engine other than  NDB  prior to execution of the statement, may also execute more efficiently. This enhancement applies to statements affecting columns of MySQL type  BLOB ,  MEDIUMBLOB , LONGBLOB ,  TEXT ,  MEDIUMTEXT , and  LONGTEXT . Statements which update  TINYBLOB  or  TINYTEXT columns (or both types) only are not affected by this work, and no changes in their performance should be expected. 3949 See Section 23.5.10, “NDB Cluster Disk Data Tables” , for more information. For more information, see Section 23.5.10.1, “NDB Cluster Disk Data Objects” .