Documentation Home
MySQL NDB Cluster 6.1 - 7.1 Release Notes
Download these Release Notes
PDF (US Ltr) - 3.0Mb
PDF (A4) - 3.0Mb

MySQL NDB Cluster 6.1 - 7.1 Release Notes  /  Changes in MySQL Cluster NDB 6.3  /  Changes in MySQL Cluster NDB 6.3.50 (5.1.66-ndb-6.3.50) (2012-12-07)

Changes in MySQL Cluster NDB 6.3.50 (5.1.66-ndb-6.3.50) (2012-12-07)

This is a bugfix release, fixing recently discovered bugs in the previous MySQL Cluster NDB 6.3 release.

Obtaining MySQL Cluster NDB 6.3.  The latest MySQL Cluster NDB 6.3 binaries for supported platforms can be obtained from Source code for the latest MySQL Cluster NDB 6.3 release can be obtained from the same location. You can also access the MySQL Cluster NDB 6.3 development source tree at

This release incorporates all bugfixes and changes made in previous MySQL Cluster releases, as well as all bugfixes and feature changes which were added in mainline MySQL 5.1 through MySQL 5.1.66 (see Changes in MySQL 5.1.66 (2012-09-28)).


Please refer to our bug database at for more details about the individual bugs fixed in this version.

Bugs Fixed

  • 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)