Oracle 5.0 Reference Manual page 1595

This timeout parameter states how long the transaction coordinator waits for query execution by
another node before aborting the transaction, and is important for both node failure handling and
deadlock detection. In MySQL 5.0.20 and earlier versions, setting it too high could cause undesirable
behavior in situations involving deadlocks and node failure. Beginning with MySQL 5.0.21, active
transactions occurring during node failures are actively aborted by the MySQL Cluster Transaction
Coordinator, and so high settings are no longer an issue with this parameter.
The default timeout value is 1200 milliseconds (1.2 seconds). The effective minimum value is 100
milliseconds; it is possible to set it as low as 50 milliseconds, but any such value is treated as 100
ms. (Bug #44099)
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NoOfDiskPagesToDiskAfterRestartTUP
Effective Version
MySQL 5.0.0
Restart Type: N
When executing a local checkpoint, the algorithm flushes all data pages to disk. Merely doing so
as quickly as possible without any moderation is likely to impose excessive loads on processors,
networks, and disks. To control the write speed, this parameter specifies how many pages per
100 milliseconds are to be written. In this context, a "page" is defined as 8KB. This parameter is
specified in units of 80KB per second, so setting
a value of entails writing 1.6MB in data pages to disk each second during a local checkpoint.
20
This value includes the writing of UNDO log records for data pages. That is, this parameter handles
the limitation of writes from data memory. UNDO log records for index pages are handled by the
parameter NoOfDiskPagesToDiskAfterRestartACC. (See the entry for
information about index pages.)
In short, this parameter specifies how quickly to execute local checkpoints. It operates in conjunction
with NoOfFragmentLogFiles, DataMemory, and IndexMemory.
For more information about the interaction between these parameters and possible strategies
for choosing appropriate values for them, see
Parameters for Local
The default value is 40 (3.2MB of data pages per second).
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NoOfDiskPagesToDiskAfterRestartACC
Effective Version
MySQL 5.0.0
Restart Type: N
This parameter uses the same units as
similar fashion, but limits the speed of writing index pages from index memory.
The default value of this parameter is 20 (1.6MB of index memory pages per second).
•
NoOfDiskPagesToDiskDuringRestartTUP
MySQL Cluster Configuration Files
Type/Units
8K pages/100
milliseconds
Checkpoints".
Type/Units
8K pages/100
milliseconds
NoOfDiskPagesToDiskAfterRestartTUP
1575
Default
40
NoOfDiskPagesToDiskAfterRestartTUP
Section 17.3.2.11, "Configuring MySQL Cluster
Default
20
Range/Values
1 - 4G
to
for
IndexMemory
Range/Values
1 - 4G
and acts in a