A slow filesystem during local checkpointing could exert undue pressure on DBDIH kernel block file page buffers, which in turn could lead to a data node crash when these were exhausted. This fix limits the number of table definition updates that DBDIH can issue concurrently. (Bug #14828998)

Setting BackupMaxWriteSize to a very large value as compared with DiskCheckpointSpeed caused excessive writes to disk and CPU usage. (Bug #14472648)

Cluster API: When the buffer pool used for KeyInfo from NDB API requests for primary key and scans was exhausted while receiving the KeyInfo, the error handling path did not correctly abort the scan request. Symptoms of this incorrect error handling included the NDB API client that requested the scan experiencing a long timeout, as well as permanent leakage of the scan record, scan fragment records, and linked operation record associated with the scan.

This issue is not present in MySQL Cluster NDB 7.0 and later, due to the replacement of the fixed-size single-purpose buffers for KeyInfo (and AttrInfo) with LongMessageBuffer, as well as improvements in error handling. (Bug #14386849)