This is a bugfix release, fixing recently discovered bugs in the previous MySQL Cluster NDB 6.3 release.
This release 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 5.1.29 (see Changes in MySQL 5.1.29 (2008-10-11)).
Please refer to our bug database at http://bugs.mysql.com/ for more details about the individual bugs fixed in this version.
Functionality Added or Changed
Important Change; Cluster API: MGM API applications exited without raising any errors if the connection to the management server was lost. The fix for this issue includes two changes:
The MGM API now provides its own
SIGPIPE handler to catch the
“broken pipe” error that occurs when writing
to a closed or reset socket. This means that MGM API now
behaves the same as NDB API in this regard.
A new function
has been added to the MGM API. This function makes it
possible to bypass the
provided by the MGM API.
Important Note; Cluster Replication:
This release of MySQL Cluster derives in part from MySQL 5.1.29,
where the default value for the
--binlog-format option changed to
STATEMENT. That change does
not affect this or future MySQL Cluster NDB
6.x releases, where the default value for this option remains
MIXED, since MySQL Cluster Replication does
not work with the statement-based format.
When performing an initial start of a data node, fragment log
files were always created sparsely—that is, not all bytes
were written. Now it is possible to override this behavior using
Failed operations on
TEXT columns were not always
reported correctly to the originating SQL node. Such errors were
sometimes reported as being due to timeouts, when the actual
problem was a transporter overload due to insufficient buffer
(Bug #39867, Bug #39879)
Undo logs and data files were created in 32K increments. Now these files are created in 512K increments, resulting in shorter creation times. (Bug #40815)
Redo log creation was very slow on some platforms, causing MySQL Cluster to start more slowly than necessary with some combinations of hardware and operating system. This was due to all write operations being synchronized to disk while creating a redo log file. Now this synchronization occurs only after the redo log has been created. (Bug #40734)
Transaction failures took longer to handle than was necessary.
When a data node acting as transaction coordinator (TC) failed, the surviving data nodes did not inform the API node initiating the transaction of this until the failure had been processed by all protocols. However, the API node needed only to know about failure handling by the transaction protocol—that is, it needed to be informed only about the TC takeover process. Now, API nodes (including MySQL servers acting as cluster SQL nodes) are informed as soon as the TC takeover is complete, so that it can carry on operating more quickly. (Bug #40697)
It was theoretically possible for stale data to be read from
NDBCLUSTER tables when the
transaction isolation level was set to
SET SESSION ndb_optimized_node_selection = 1
failed with an invalid warning message.
A restarting data node could fail with an error in the
DBDIH kernel block when a local or global
checkpoint was started or triggered just as the node made a
request for data from another data node.
Restoring a MySQL Cluster from a dump made using mysqldump failed due to a spurious error: Can't execute the given command because you have active locked tables or an active transaction. (Bug #40346)
O_DIRECT was incorrectly disabled when making
MySQL Cluster backups.
Heavy DDL usage caused the mysqld processes
to hang due to a timeout error (
error code 266).
Events logged after setting
STATISTICS=15 in the management client did not always
include the node ID of the reporting node.
A segfault in
ndbd to hang indefinitely. This fix improves
on an earlier one for this issue, first made in MySQL Cluster
NDB 6.2.16 and MySQL Cluster NDB 6.3.17.
References: See also Bug #38609.
Memory leaks could occur in handling of strings used for storing cluster metadata and providing output to users. (Bug #38662)
A duplicate key or other error raised when inserting into an
NDBCLUSTER table caused the current
transaction to abort, after which any SQL statement other than a
failed. With this fix, the
NDBCLUSTER storage engine now
performs an implicit rollback when a transaction is aborted in
this way; it is no longer necessary to issue an explicit
statement, and the next statement that is issued automatically
begins a new transaction.
It remains necessary in such cases to retry the complete transaction, regardless of which statement caused it to be aborted.
References: See also Bug #47654.
Error messages for
codes 1224 and 1227 were missing.
Dropping or creating an index on a partitioned table managed by
InnoDB Plugin locked the table.
GROUP statements on separate SQL nodes caused a
resource leak that led to data node crashes when these
statements were used again later.
Disk Data: Disk-based variable-length columns were not always handled like their memory-based equivalents, which could potentially lead to a crash of cluster data nodes. (Bug #39645)
O_SYNC was incorrectly disabled on platforms
that do not support
O_DIRECT. This issue was
noted on Solaris but could have affected other platforms not
Cluster API: The MGM API reset error codes on management server handles before checking them. This meant that calling an MGM API function with a null handle caused applications to crash. (Bug #40455)
It was not always possible to access parent objects directly
NdbScanOperation objects. To
alleviate this problem, a new
method has been added to
NdbBlob and new
getNdbTransaction() methods have been added to
NdbScanOperation. In addition,
a const variant of
NdbOperation::getErrorLine() is now also
getBlobHandle() failed when used with
incorrect column names or numbers.
The MGM API function
As part of this fix, it is now possible to specify bind addresses in connection strings. See MySQL Cluster Connection Strings, for more information. (Bug #38473)
Cluster API: The NDB API example programs included in MySQL Cluster source distributions failed to compile. (Bug #37491)
References: See also Bug #40238.