MySQL Cluster NDB 7.3.3 is a new release of MySQL Cluster, based
on MySQL Server 5.6 and including features from version 7.3 of the
NDB storage engine, as well as fixing
a number of recently discovered bugs in previous MySQL Cluster
Obtaining MySQL Cluster NDB 7.3. MySQL Cluster NDB 7.3 source code and binaries can be obtained from http://dev.mysql.com/downloads/cluster/.
For an overview of changes made in MySQL Cluster NDB 7.3, see MySQL Cluster Development in MySQL Cluster NDB 7.3.
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 5.6 through MySQL 5.6.14 (see Changes in MySQL 5.6.14 (2013-09-20)).
The length of time a management node waits for a heartbeat message from another management node is now configurable using the
HeartbeatIntervalMgmdMgmdmanagement node configuration parameter added in this release. The connection is considered dead after 3 missed heartbeats. The default value is 1500 milliseconds, or a timeout of approximately 6000 ms. (Bug #17807768, Bug #16426805)
The MySQL Cluster Auto-Installer now generates a
my.cnffile for each mysqld in the cluster before starting it. For more information, see Using the MySQL Cluster Auto-Installer. (Bug #16994782)
Performance: In a number of cases found in various locations in the MySQL Cluster codebase, unnecessary iterations were performed; this was caused by failing to break out of a repeating control structure after a test condition had been met. This community-contributed fix removes the unneeded repetitions by supplying the missing breaks. (Bug #16904243, Bug #69392, Bug #16904338, Bug #69394, Bug #16778417, Bug #69171, Bug #16778494, Bug #69172, Bug #16798410, Bug #69207, Bug #16801489, Bug #69215, Bug #16904266, Bug #69393)
Packaging: Portions of the documentation specific to MySQL Cluster and the
NDBstorage engine were not included when installing from RPMs. (Bug #16303451)
ndb_restore could abort during the last stages of a restore using attribute promotion or demotion into an existing table. This could happen if a converted attribute was nullable and the backup had been run on active database. (Bug #17275798)
It was not possible to start MySQL Cluster processes created by the Auto-Installer on a Windows host running freeSSHd. (Bug #17269626)
DBUTILdata node block is now less strict about the order in which it receives certain messages from other nodes. (Bug #17052422)
ALTER ONLINE TABLE ... REORGANIZE PARTITIONfailed when run against a table having or using a reference to a foreign key. (Bug #17036744, Bug #69619)
TUPKEYREQsignals are used to read data from the tuple manager block (
DBTUP), and are used for all types of data access, especially for scans which read many rows. A TUPKEYREQ specifies a series of 'columns' to be read, which can be either single columns in a specific table, or pseudocolumns, two of which—
READ_PACKED—are aliases to read all columns in a table, or some subset of these columns. Pseudocolumns are used by modern NDB API applications as they require less space in the
TUPKEYREQto specify columns to be read, and can return the data in a more compact (packed) format.
This fix moves the creation and initialization of on-stack Signal objects to only those pseudocolumn reads which need to
EXECUTE_DIRECTto other block instances, rather than for every read. In addition, the size of an on-stack signal is now varied to suit the requirements of each pseudocolumn, so that only reads of the
INDEX_STATpseudocolumn now require initialization (and 3KB memory each time this is performed). (Bug #17009502)
A race condition could sometimes occur when trying to lock receive threads to cores. (Bug #17009393)
Results from joins using a
ORDER BY ... DESCclause were not sorted properly; the
DESCkeyword in such cases was effectively ignored. (Bug #16999886, Bug #69528)
The Windows error ERROR_FILE_EXISTS was not recognized by
NDB, which treated it as an unknown error. (Bug #16970960)
RealTimeSchedulerdid not work correctly with data nodes running ndbmtd. (Bug #16961971)
File system errors occurring during a local checkpoint could sometimes cause an LCP to hang with no obvious cause when they were not handled correctly. Now in such cases, such errors always cause the node to fail. Note that the LQH block always shuts down the node when a local checkpoint fails; the change here is to make likely node failure occur more quickly and to make the original file system error more visible. (Bug #16961443)
Maintenance and checking of parent batch completion in the
SPJblock of the
NDBkernel was reimplemented. Among other improvements, the completion state of all ancestor nodes in the tree are now preserved. (Bug #16925513)
Dropping a column, which was not itself a foreign key, from an
NDBtable having foreign keys failed with ER_TABLE_DEF_CHANGED. (Bug #16912989)
The LCP fragment scan watchdog periodically checks for lack of progress in a fragment scan performed as part of a local checkpoint, and shuts down the node if there is no progress after a given amount of time has elapsed. This interval, formerly hard-coded as 60 seconds, can now be configured using the
LcpScanProgressTimeoutdata node configuration parameter added in this release.
This configuration parameter sets the maximum time the local checkpoint can be stalled before the LCP fragment scan watchdog shuts down the node. The default is 60 seconds, which provides backward compatibility with previous releases.
You can disable the LCP fragment scan watchdog by setting this parameter to 0. (Bug #16630410)
Added the ndb_error_reporter options
--connection-timeout, which makes it possible to set a timeout for connecting to nodes,
--dry-scp, which disables scp connections to remote hosts, and
--skip-nodegroup, which skips all nodes in a given node group. (Bug #16602002)
References: See also Bug #11752792, Bug #44082.
START BACKUP, if
idhad already been used for a backup ID, an error caused by the duplicate ID occurred as expected, but following this, the
START BACKUPcommand never completed. (Bug #16593604, Bug #68854)
ndb_mgm treated backup IDs provided to
ABORT BACKUPcommands as signed values, so that backup IDs greater than 231 wrapped around to negative values. This issue also affected out-of-range backup IDs, which wrapped around to negative values instead of causing errors as expected in such cases. The backup ID is now treated as an unsigned value, and ndb_mgm now performs proper range checking for backup ID values greater than
MAX_BACKUPS(232). (Bug #16585497, Bug #68798)
When trying to specify a backup ID greater than the maximum allowed, the value was silently truncated. (Bug #16585455, Bug #68796)
The unexpected shutdown of another data node as a starting data node received its node ID caused the latter to hang in Start Phase 1. (Bug #16007980)
References: See also Bug #18993037.
NDBreceive thread waited unnecessarily for additional job buffers to become available when receiving data. This caused the receive mutex to be held during this wait, which could result in a busy wait when the receive thread was running with real-time priority.
This fix also handles the case where a negative return value from the initial check of the job buffer by the receive thread prevented further execution of data reception, which could possibly lead to communication blockage or configured
ReceiveBufferMemoryunderutilization. (Bug #15907515)
When the available job buffers for a given thread fell below the critical threshold, the internal multi-threading job scheduler waited for job buffers for incoming rather than outgoing signals to become available, which meant that the scheduler waited the maximum timeout (1 millisecond) before resuming execution. (Bug #15907122)
lower_case_table_namesto 1 or 2 on Windows systems caused
ALTER TABLE ... ADD FOREIGN KEYstatements against tables with names containing uppercase letters to fail with Error 155, No such table: '(null)'. (Bug #14826778, Bug #67354)
Under some circumstances, a race occurred where the wrong watchdog state could be reported. A new state name
Packing Send Buffersis added for watchdog state number 11, previously reported as
Unknown place. As part of this fix, the state numbers for states without names are always now reported in such cases. (Bug #14824490)
When a node fails, the Distribution Handler (
DBDIHkernel block) takes steps together with the Transaction Coordinator (
DBTC) to make sure that all ongoing transactions involving the failed node are taken over by a surviving node and either committed or aborted. Transactions taken over which are then committed belong in the epoch that is current at the time the node failure occurs, so the surviving nodes must keep this epoch available until the transaction takeover is complete. This is needed to maintain ordering between epochs.
A problem was encountered in the mechanism intended to keep the current epoch open which led to a race condition between this mechanism and that normally used to declare the end of an epoch. This could cause the current epoch to be closed prematurely, leading to failure of one or more surviving data nodes. (Bug #14623333, Bug #16990394)
LongMessageBuffermemory under heavy load could cause data nodes running ndbmtd to fail. (Bug #14488185)
When using dynamic listening ports for accepting connections from API nodes, the port numbers were reported to the management server serially. This required a round trip for each API node, causing the time required for data nodes to connect to the management server to grow linearly with the number of API nodes. To correct this problem, each data node now reports all dynamic ports at once. (Bug #12593774)
ndb_error-reporter did not support the
--helpoption. (Bug #11756666, Bug #48606)
References: See also Bug #11752792, Bug #44082.
Formerly, the node used as the coordinator or leader for distributed decision making between nodes (also known as the
DICTmanager—see The DBDICT Block) was indicated in the output of the ndb_mgm client
SHOWcommand as the “master” node, although this node has no relationship to a master server in MySQL Replication. (It should also be noted that it is not necessary to know which node is the leader except when debugging
NDBCLUSTERsource code.) To avoid possible confusion, this label has been removed, and the leader node is now indicated in
SHOWcommand output using an asterisk (
*) character. (Bug #11746263, Bug #24880)
The matrix of values used for thread configuration when applying the setting of the
MaxNoOfExecutionThreadsconfiguration parameter has been improved to align with support for greater numbers of LDM threads. See Multi-Threading Configuration Parameters (ndbmtd), for more information about the changes. (Bug #75220, Bug #20215689)
Program execution failed to break out of a loop after meeting a desired condition in a number of internal methods, performing unneeded work in all cases where this occurred. (Bug #69610, Bug #69611, Bug #69736, Bug #17030606, Bug #17030614, Bug #17160263)
ABORT BACKUPin the ndb_mgm client (see Commands in the MySQL Cluster Management Client) took an excessive amount of time to return (approximately as long as the backup would have required to complete, had it not been aborted), and failed to remove the files that had been generated by the aborted backup. (Bug #68853, Bug #17719439)
Note that converted character data is not checked to conform to any character set.
When performing such promotions, the only other sort of type conversion that can be performed at the same time is between character types and binary types.
Cluster Replication: Trying to use a stale
.frmfile and encountering a mismatch bewteen table definitions could cause mysqld to make errors when writing to the binary log. (Bug #17250994)
Cluster Replication: Replaying a binary log that had been written by a mysqld from a MySQL Server distribution (and from not a MySQL Cluster distribution), and that contained DML statements, on a MySQL Cluster SQL node could lead to failure of the SQL node. (Bug #16742250)
Cluster API: The
Event::setTable()method now supports a pointer or a reference to table as its required argument. If a null table pointer is used, the method now returns -1 to make it clear that this is what has occurred. (Bug #16329082)
ndbmemcache: When attempting to start memcached with a
cache_sizelarger than that of the available memory and with
preallocate=truefailed, the error message provided only a numeric code, and did not indicate what the actual source of the error was. (Bug #17509293, Bug #70403)
ndbmemcachewrote into the source tree, preventing out-of-source builds. (Bug #14650456)
ndbmemcachedid not handle passed-in