This release incorporates new features in the
NDB storage engine and fixes
recently discovered bugs in previous MySQL Cluster NDB 7.0
Obtaining MySQL Cluster NDB 7.0. The latest MySQL Cluster NDB 7.0 binaries for supported platforms can be obtained from http://dev.mysql.com/downloads/cluster/. Source code for the latest MySQL Cluster NDB 7.0 release can be obtained from the same location. You can also access the MySQL Cluster NDB 7.0 development source tree at https://code.launchpad.net/~mysql/mysql-server/mysql-cluster-7.0.
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 5.1.72 (see Changes in MySQL 5.1.72 (2013-09-20)).
Please refer to our bug database at http://bugs.mysql.com/ for more details about the individual bugs fixed in this version.
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)
Monotonic timers on several platforms can experience issues which might result in the monotonic clock doing small jumps back in time. This is due to imperfect synchronization of clocks between multiple CPU cores and does not normally have an adverse effect on the scheduler and watchdog mechanisms; so we handle some of these cases by making backtick protection less strict, although we continue to ensure that the backtick is less than 10 milliseconds. This fix also removes several checks for backticks which are thereby made redundant. (Bug #17973819)
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)
DBUTILdata node block is now less strict about the order in which it receives certain messages from other nodes. (Bug #17052422)
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)
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.
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)
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)
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)
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.
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)