MySQL Lists are EOL. Please join:

List:General Discussion« Previous MessageNext Message »
From:daniel.horecki Date:January 23 2018 3:35pm
Subject:MySQL Cluster 7.4.19 has been released
View as plain text  
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 7.4.19, has been released and can be downloaded from

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

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

Enjoy !

Changes in MySQL NDB Cluster 7.4.19 (5.6.39-ndb-7.4.19)
(2018-01-23, General Availability)

    MySQL NDB Cluster 7.4.19 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.

    NDB 7.4.19 replaces the NDB 7.4.18 release, and is the
    successor to NDB 7.4.17. Users of NDB 7.4.17 and previous NDB
    7.4 releases should upgrade directly to MySQL NDB Cluster
    7.4.19 or newer.

    Obtaining MySQL NDB Cluster 7.4.  MySQL NDB Cluster 7.4
    source code and binaries can be obtained from

    For an overview of changes made in MySQL NDB Cluster 7.4, see
    What is New in NDB Cluster 7.4

    This release also incorporates all bug fixes and changes made
    in previous NDB Cluster releases (including the NDB 7.4.18
    release which this release replaces), as well as all bug
    fixes and feature changes which were added in mainline MySQL
    5.6 through MySQL 5.6.39 (see Changes in MySQL 5.6.39
    (2018-01-15, General Availability)

    Bugs Fixed

      * NDB Replication: On an SQL node not being used for a
        replication channel with sql_log_bin=0 it was
        after creating and populating an NDB table for a
        map event to be written to the binary log for the
        table with no corresponding row events. This led to
        problems when this log was later used by a slave
        replicating from the mysqld where this table was
        Fixed this by adding support for maintaining a
        any_value bitmap for global checkpoint event
        that represents bits set consistently for all rows
of a
        specific table in a given epoch, and by adding a
check to
        determine whether all operations (rows) for a
        table are all marked as NOLOGGING, to prevent the
        addition of this table to the Table_map held by the
        binlog injector.
        As part of this fix, the NDB API adds a new
        getNextEventOpInEpoch3() method which provides
        information about any AnyValue received by making it
        possible to retrieve the cumulative any_value
        (Bug #26333981)

      * A query against the INFORMATION_SCHEMA.FILES table
        returned no results when it included an ORDER BY
        (Bug #26877788)

      * During a restart, DBLQH loads redo log part metadata for
        each redo log part it manages, from one or more redo
        files. Since each file has a limited capacity for
        metadata, the number of files which must be
        depends on the size of the redo log part. These
files are
        opened, read, and closed sequentially, but the
closing of
        one file occurs concurrently with the opening of the
        In cases where closing of the file was slow, it was
        possible for more than 4 files per redo log part to
        open concurrently; since these files were opened
        the OM_WRITE_BUFFER option, more than 4 chunks of
        buffer were allocated per part in such cases. The
        buffer pool is not unlimited; if all redo log parts
        in a similar state, the pool was exhausted, causing
        data node to shut down.
        This issue is resolved by avoiding the use of
        OM_WRITE_BUFFER during metadata reload, so that any
        transient opening of more than 4 redo log files per
        file part no longer leads to failure of the data
        (Bug #25965370)

      * When the duplicate weedout algorithm was used for
        evaluating a semi-join, the result had missing rows.
        (Bug #88117, Bug #26984919)
        References: See also: Bug #87992, Bug #26926666.

      * When representing a materialized semi-join in the query
        plan, the MySQL Optimizer inserted extra QEP_TAB and
        JOIN_TAB objects to represent access to the
        subquery result. The join pushdown analyzer did not
        properly set up its internal data structures for
        leaving them uninitialized instead. This meant that
        usage of any item objects referencing the
        semi-join accessed an initialized tableno column
        accessing a 64-bit tableno bitmask, possibly
referring to
        a point beyond its end, leading to an unplanned
        of the SQL node. (Bug #87971, Bug #26919289)

      * The NDBFS block's OM_SYNC flag is intended to make sure
        that all FSWRITEREQ signals used for a given file
        synchronized, but was ignored by platforms that do
        support O_SYNC, meaning that this feature did not
        properly on those platforms. Now the synchronization
        is used on those platforms that do not support
        (Bug #76975, Bug #21049554)

MySQL Cluster 7.4.19 has been releaseddaniel.horecki23 Jan