The following list provides an overview of significant feature additions and changes made in MySQL Cluster NDB 6.2. All of the changes in this list are also available in MySQL Cluster NDB 6.3 . For more detailed information about all feature changes and bugfixes made in MySQL Cluster NDB 6.2, see Section 20.17.2, “Changes in MySQL Cluster NDB 6.2”.
Enhanced backup status reporting.
Backup status reporting has been improved, aided in part
by the introduction of a
BackupReportFrequency configuration
parameter; see
Defining
Data Nodes:
BackupReportFrequency,
for more information.
Multiple cluster connections per SQL node.
A single MySQL server acting as a MySQL Cluster SQL node
can employ multiple connections to the cluster using the
--ndb-cluster-connection-pool startup
option for mysqld. This option is
described in
MySQL
Cluster-Related Command Options for
mysqld:
--ndb-cluster-connection-pool
option.
New data access interface.
The NdbRecord interface provides a new
and simplified data handler for use in NDB API
applications. See The NdbRecord Interface,
for more information.
New reporting commands.
The new management client REPORT
BackupStatus and REPORT
MemoryUsage commands provide better access to
information about the status of MySQL Cluster backups and
how much memory is being used by MySQL Cluster for data
and index storage. See
Section 20.7.2, “Commands in the MySQL Cluster Management Client”, for
more information about the REPORT
commands. In addition, in-progress status reporting is
provided by the ndb_restore utility;
see Section 20.9.3, “ndb_restore — Restore a Cluster Backup”.
Improved memory allocation and configuration.
Memory is now allocated by the NDB
kernel to tables on a page-by-page basis, which
significantly reduces the memory overhead required for
maintaining NDBCLUSTER tables. In
addition, the MaxAllocate configuration
parameter now makes it possible to set the maximum size of
the allocation unit used for table memory; for more
information about this configuration parameter, see
Defining
Data Nodes:
MaxAllocate.
Choice of fixed-width or variable-width columns.
You can control whether fixed-width or variable-width
storage is used for a given column of an
NDB table by employing of the
COLUMN_FORMAT specifier as part of the
column's definition in a CREATE
TABLE or ALTER TABLE
statement. In addition, the ability to control whether a
given column of an NDB table is stored
in memory or on disk, using the STORAGE
specifier as part of the column's definition in a
CREATE TABLE or ALTER
TABLE statement. For more information, see
Section 12.1.10, “CREATE TABLE Syntax”, and
Section 12.1.4, “ALTER TABLE Syntax”.
Controlling management client connections.
The --bind-address cluster management
server startup option makes it possible to restrict
management client connections to
ndb_mgmd to a single host (IP address
or hostname) and port, which can make MySQL Cluster
management operations more secure. For more information
about this option, see
Section 20.6.5.2, “Command Options for ndb_mgmd”.
Micro-GCPs.
Due to a change in the protocol for handling of global
checkpoints (GCPs handled in this manner sometimes being
referred to as “micro-GCPs”), it is now
possible to control how often the GCI number is updated,
and how often global checkpoints are written to disk,
using the TimeBetweenEpochs
configuration parameter. This improves the reliability and
performance of MySQL Cluster Replication. For more
information, see
Defining
Data Nodes:
TimeBetweenEpochs
and
Defining
Data Nodes:
TimeBetweenEpochsTimeout.
Core online schema change support.
Support for the online ALTER TABLE
operations ADD COLUMN, ADD
INDEX, and DROP INDEX is
available. When the ONLINE keyword is
used, the ALTER TABLE is non-copying,
which means that indexes do not have to be re-created,
which provides these benefits:
Single user mode is no longer required for
ALTER TABLE operations that can
be performed online.
Transactions can continue during ALTER
TABLE operations that can be performed
online.
Tables being altered online are not locked.
Online CREATE INDEX and DROP
INDEX statements are also supported. Online
changes can be suppressed using the
OFFLINE key word. See
Section 12.1.4, “ALTER TABLE Syntax”,
Section 12.1.7, “CREATE INDEX Syntax”, and
Section 12.1.13, “DROP INDEX Syntax”, for more detailed
information.
mysql.ndb_binlog_index improvements.
More information has been added to the
mysql.ndb_binlog_index table so that it
is possible to determine which originating epochs have
been applied inside an epoch. This is particularly useful
for 3-way replication. See
Section 20.11.4, “Cluster Replication Schema and Tables”, for
more information.
Epoch lag control.
The MaxBufferedEpochs data node
configuration parameter provides a means to control the
maximum number of unprocessed epochs by which a
subscribing node can lag. Subscribers which exceed this
number are disconnected and forced to reconnect. For a
discussion of this configuration parameter, see
Defining
Data Nodes:
MaxBufferedEpochs.

User Comments
Add your own comment.