MySQL Cluster 7.4.23 has been released

[Nawaz Nazeer ahamed]

Dear MySQL Users,

MySQL Cluster is the distributed, shared-nothing variant of MySQL.  This
storage engine provides:

  - In-Memory storage - Real-time performance
  - Transparent Auto-Sharding - Read & write scalability
  - Active-Active/Multi-Master geographic replication
  - 99.999% High Availability with no single point of failure
    and on-line maintenance
  - NoSQL and SQL APIs (including C++, Java, http, Memcached
    and JavaScript/Node.js)

MySQL Cluster 7.4 makes significant advances in performance; operational
efficiency (such as enhanced reporting and faster restarts and upgrades)
and conflict detection and resolution for active-active replication
between MySQL Clusters.

MySQL Cluster 7.4.23 has been released and can be downloaded from

  http://www.mysql.com/downloads/cluster/

where you will also find Quick Start guides to help you get your first
MySQL Cluster database up and running.

The release notes are available from

  http://dev.mysql.com/doc/relnotes/mysql-cluster/7.4/en/index.html

MySQL Cluster enables users to meet the database challenges of next
generation web, cloud, and communications services with uncompromising
scalability, uptime and agility.

More details can be found at

  http://www.mysql.com/products/cluster/

Enjoy !

==============================================================================
Changes in MySQL NDB Cluster 7.4.23 (5.6.43-ndb-7.4.23) (2019-01-22,
General Availability)

   MySQL NDB Cluster 7.4.23 is a new release of MySQL NDB Cluster 7.4,
   based on MySQL Server 5.6 and including features in version 7.4 of
   the NDB storage engine, as well as fixing recently discovered bugs in
   previous NDB Cluster releases.

   Obtaining MySQL NDB Cluster 7.4.  MySQL NDB Cluster 7.4 source code
   and binaries can be obtained from
   https://dev.mysql.com/downloads/cluster/.

   For an overview of changes made in MySQL NDB Cluster 7.4, see What is
   New in NDB Cluster 7.4
(http://dev.mysql.com/doc/refman/5.6/en/mysql-cluster-what-is-new-7-4.html).

   This release also incorporates all bug fixes and changes made in
   previous NDB Cluster releases, as well as all bug fixes and feature
   changes which were added in mainline MySQL 5.6 through MySQL 5.6.43
   (see Changes in MySQL 5.6.43 (2019-01-21, General Availability)
   (http://dev.mysql.com/doc/relnotes/mysql/5.6/en/news-5-6-43.html)).

Bugs Fixed


     * NDB Replication: When writes on the master---done in such
       a way that multiple changes affecting BLOB column values
       belonging to the same primary key were part of the same
       epoch---were replicated to the slave, Error 1022 occurred due to
       constraint violations in the NDB$BLOB_id_part table.
       (Bug #28746560)

     * When only the management server but no data nodes were
       started, RESTART ALL timed out and eventually failed.  This was
       because, as part of a restart, ndb_mgmd starts a timer, sends a
       STOP_REQ signal to all the data nodes, and waits for all of them
       to reach node state SL_CMVMI. The issue arose becaue no STOP_REQ
       signals were ever sent, and thus no data nodes reached SL_CMVMI.
       This meant that the timer always expired, causing the restart to
       fail.  (Bug #28728485, Bug #28698831)
       References: See also: Bug #11757421.

     * It was possible in certain cases for nodes to hang during
       an initial restart. (Bug #28698831)
       References: See also: Bug #27622643.

     * When running a cluster with 4 or more data nodes under
       very high loads, data nodes could sometimes fail with Error 899
       Rowid already allocated. (Bug #25960230)

     * When starting, a data node copies metadata, while a local
       checkpoint updates metadata. To avoid any conflict, any ongoing
       LCP activity is paused while metadata is being copied. An issue
       arose when a local checkpoint was paused on a given node, and
       another node that was also restarting checked for a complete LCP
       on this node; the check actually caused the LCP to be completed
       before copying of metadata was complete and so ended the pause
       prematurely. Now in such cases, the LCP completion check waits to
       complete a paused LCP until copying of metadata is finished and
       the pause ends as expected, within the LCP in which it began.
       (Bug #24827685)

     * Asynchronous disconnection of mysqld from the cluster
       caused any subsequent attempt to start an NDB API transaction to
       fail. If this occurred during a bulk delete operation, the SQL
       layer called HA::end_bulk_delete(), whose implementation by
       ha_ndbcluster assumed that a transaction had been started, and
       could fail if this was not the case. This problem is fixed by
       checking that the transaction pointer used by this method is set
       before referencing it. (Bug #20116393)


Enjoy and thanks for the support!

On behalf of the MySQL Release Team,
Nawaz Nazeer Ahamed