Oracle 5.0, Reference Manual

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MySQL Cluster Configuration Files
1578
RedoBuffer
Effective Version Type/Units Default Range/Values
MySQL 5.0.0 bytes 8M 1M - 4G
Restart Type: N
All update activities also need to be logged. The REDO log makes it possible to replay these updates
whenever the system is restarted. The NDB recovery algorithm uses a “fuzzy” checkpoint of the
data together with the UNDO log, and then applies the REDO log to play back all changes up to the
restoration point.
RedoBuffer
sets the size of the buffer in which the REDO log is written, and is 8MB by default. The
minimum value is 1MB.
If this buffer is too small, the NDB storage engine issues error code 1221 (
REDO log buffers
overloaded
).
Important
It is not safe to decrease the value of this parameter during a rolling restart.
Controlling log messages. In managing the cluster, it is very important to be able to control the
number of log messages sent for various event types to
stdout
. For each event category, there are
16 possible event levels (numbered 0 through 15). Setting event reporting for a given event category
to level 15 means all event reports in that category are sent to
stdout
; setting it to 0 means that there
will be no event reports made in that category.
By default, only the startup message is sent to
stdout
, with the remaining event reporting level
defaults being set to 0. The reason for this is that these messages are also sent to the management
server's cluster log.
An analogous set of levels can be set for the management client to determine which event levels to
record in the cluster log.
•
LogLevelStartup
Effective Version Type/Units Default Range/Values
MySQL 5.0.0 integer 1 0 - 15
Restart Type: N
The reporting level for events generated during startup of the process.
The default level is 1.
•
LogLevelShutdown
Effective Version Type/Units Default Range/Values
MySQL 5.0.0 integer 0 0 - 15
Restart Type: N
The reporting level for events generated as part of graceful shutdown of a node.
The default level is 0.
•