Dear MySQL users,
MySQL Cluster is the distributed, shared-nothing variant of MySQL. This
storage engine provides:
- Real-time performance based on in-memory storage (with
checkpointing to disk)
- Read & write scalability through transparent auto-sharding
- 99.999% High Availability with no single point of failure and
- SQL and NoSQL API (including C++, Java, and http)
- Active-Active/Multi-Master geographic replication
MySQL Cluster 7.1.32, 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
Changes in MySQL Cluster NDB 7.1.32 (5.1.73-ndb-7.1.32) (2014-07-15)
MySQL Cluster NDB 7.1.32 is a new release of MySQL Cluster,
incorporating new features in the NDBCLUSTER storage engine and
fixing recently discovered bugs in previous MySQL Cluster NDB 7.1
Obtaining MySQL Cluster NDB 7.1. The latest MySQL Cluster NDB 7.1
binaries for supported platforms can be obtained from
http://dev.mysql.com/downloads/cluster/. Source code for the
latest MySQL Cluster NDB 7.1 release can be obtained from the same
location. You can also access the MySQL Cluster NDB 7.1
development source tree at
This release also 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 5.1.73 (see Changes in MySQL 5.1.73 (2013-12-03)
Functionality Added or Changed
* Cluster API: Added as an aid to debugging the ability to
specify a human-readable name for a given Ndb object and later
to retrieve it. These operations are implemented,
respectively, as the setNdbObjectName() and getNdbObjectName()
To make tracing of event handling between a user application
and NDB easier, you can use the reference (from getReference()
followed by the name (if provided) in printouts; the reference
ties together the application Ndb object, the event buffer,
and the NDB storage engine's SUMA block. (Bug #18419907)
* Processing a NODE_FAILREP signal that contained an invalid
node ID could cause a data node to fail. (Bug #18993037, Bug
References: This bug is a regression of Bug #16007980.
* ndbmtd supports multiple parallel receiver threads, each of
which performs signal reception for a subset of the remote
node connections (transporters) with the mapping of
remote_nodes to receiver threads decided at node startup.
Connection control is managed by the multi-instance TRPMAN
block, which is organized as a proxy and workers, and each
receiver thread has a TRPMAN worker running locally.
The QMGR block sends signals to TRPMAN to enable and disable
communications with remote nodes. These signals are sent to
the TRPMAN proxy, which forwards them to the workers. The
workers themselves decide whether to act on signals, based on
the set of remote nodes they manage.
The current isuue arises because the mechanism used by the
TRPMAN workers for determining which connections they are
responsible for was implemented in such a way that each worker
thought it was responsible for all connections. This resulted
in the TRPMAN actions for OPEN_COMORD, ENABLE_COMREQ, and
CLOSE_COMREQ being processed multiple times.
The fix keeps TRPMAN instances (receiver threads) executing
OPEN_COMORD, ENABLE_COMREQ and CLOSE_COMREQ requests. In
addition, the correct TRPMAN instance is now chosen when
routing from this instance for a specific remote connection.
* Executing ALTER TABLE ... REORGANIZE PARTITION after
increasing the number of data nodes in the cluster from 4 to
16 led to a crash of the data nodes. This issue was shown to
be a regression caused by previous fix which added a new dump
handler using a dump code that was already in use (7019),
which caused the command to execute two different handlers
with different semantics. The new handler was assigned a new
DUMP code (7024). (Bug #18550318)
References: This bug is a regression of Bug #14220269.
* A local checkpoint (LCP) is tracked using a global LCP state
(c_lcpState), and each NDB table has a status indicator which
indicates the LCP status of that table (tabLcpStatus). If the
global LCP state is LCP_STATUS_IDLE, then all the tables
should have an LCP status of TLS_COMPLETED.
When an LCP starts, the global LCP status is LCP_INIT_TABLES
and the thread starts setting all the NDB tables to
TLS_ACTIVE. If any tables are not ready for LCP, the LCP
initialization procedure continues with CONTINUEB signals
until all tables have become available and been marked
TLS_ACTIVE. When this initialization is complete, the global
LCP status is set to LCP_STATUS_ACTIVE.
This bug occurred when the following conditions were met:
+ An LCP was in the LCP_INIT_TABLES state, and some but not
all tables had been set to TLS_ACTIVE.
+ The master node failed before the global LCP state
changed to LCP_STATUS_ACTIVE; that is, before the LCP
could finish processing all tables.
+ The NODE_FAILREP signal resulting from the node failure
was processed before the final CONTINUEB signal from the
LCP initialization process, so that the node failure was
processed while the LCP remained in the LCP_INIT_TABLES
Following master node failure and selection of a new one, the
new master queries the remaining nodes with a MASTER_LCPREQ
signal to determine the state of the LCP. At this point, since
the LCP status was LCP_INIT_TABLES, the LCP status was reset
to LCP_STATUS_IDLE. However, the LCP status of the tables was
not modified, so there remained tables with TLS_ACTIVE.
Afterwards, the failed node is removed from the LCP. If the
LCP status of a given table is TLS_ACTIVE, there is a check
that the global LCP status is not LCP_STATUS_IDLE; this check
failed and caused the data node to fail.
Now the MASTER_LCPREQ handler ensures that the tabLcpStatus
for all tables is updated to TLS_COMPLETED when the global LCP
status is changed to LCP_STATUS_IDLE. (Bug #18044717)
* The logging of insert failures has been improved. This is
intended to help diagnose occasional issues seen when writing
to the mysql.ndb_binlog_index table. (Bug #17461625)
* Employing a CHAR column that used the UTF8 character set as a
table's primary key column led to node failure when restarting
data nodes. Attempting to restore a table with such a primary
key also caused ndb_restore to fail. (Bug #16895311, Bug
* Cluster Replication: When using NDB$EPOCH_TRANS, conflicts
between DELETE operations were handled like conflicts between
updates, with the primary rejecting the transaction and
dependents, and realigning the secondary. This meant that
their behavior with regard to subsequent operations on any
affected row or rows depended on whether they were in the same
epoch or a different one: within the same epoch, they were
considered conflicting events; in different epochs, they were
not considered in conflict.
This fix brings the handling of conflicts between deletes by
NDB$EPOCH_TRANS with that performed when using NDB$EPOCH for
conflict detection and resolution, and extends testing with
NDB$EPOCH and NDB$EPOCH_TRANS to include "delete-delete"
conflicts, and encapsulate the expected result, with
transactional conflict handling modified so that a conflict
between DELETE operations alone is not sufficient to cause a
transaction to be considered in conflict. (Bug #18459944)
* Cluster API: When an NDB data node indicates a buffer overflow
via an empty epoch, the event buffer places an inconsistent
data event in the event queue. When this was consumed, it was
not removed from the event queue as expected, causing
subsequent nextEvent() calls to return 0. This caused event
consumption to stall because the inconsistency remained
flagged forever, while event data accumulated in the queue.
Event data belonging to an empty inconsistent epoch can be
found either at the beginning or somewhere in the middle.
pollEvents() returns 0 for the first case. This fix handles
the second case: calling nextEvent() call dequeues the
inconsistent event before it returns. In order to benefit from
this fix, user applications must call nextEvent() even when
pollEvents() returns 0. (Bug #18716991)
* Cluster API: The pollEvents() method returned 1, even when
called with a wait time equal to 0, and there were no events
waiting in the queue. Now in such cases it returns 0 as
expected. (Bug #18703871)
On behalf of the MySQL Cluster and the Oracle/MySQL RE Team,
|• MySQL Cluster 7.1.32 has been released||Hery Ramilison||16 Jul 2014|