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ENGINE NDBCLUSTER; 

This logfile group is created when the data nodes are started with --initial . 

Resources for the initial log file group are added to the global memory pool along with those indicated by the value of SharedGlobalMemory . 

This parameter, if used, should always be set in the [ndbd default]  section of the config.ini file. The behavior of an NDB Cluster when different values are set on different data nodes is not defined. 

• InitialTablespace 

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This parameter can be used to specify an NDB Cluster Disk Data tablespace that is created when performing an initial start of the cluster. InitialTablespace  is specified as shown here: 

InitialTablespace = [name= name ;] [extent_size= size ;] file-specification-list 

The name  of the tablespace is optional and defaults to DEFAULT-TS . The extent_size  is also optional; it defaults to 1M . The file-specification-list  uses the same syntax as shown with the InitialLogfileGroup  parameter, the only difference being that each file-specification used with InitialTablespace  corresponds to a data file. At least one must be specified in the file-specification-list . Data files are placed according to any values that have been set for FileSystemPath , FileSystemPathDD , and FileSystemPathDataFiles , just as if they had been created as the result of a CREATE TABLESPACE  or ALTER TABLESPACE  statement. 

For example, consider the following line specifying InitialTablespace  in the [ndbd default] section of the config.ini  file (as with InitialLogfileGroup , this parameter should always be set in the [ndbd default]  section, as the behavior of an NDB Cluster when different values are set on different data nodes is not defined): 

InitialTablespace = name=TS1; extent_size=8M; data1.dat:2G; data2.dat:4G 

This is equivalent to the following SQL statements: 

CREATE TABLESPACE TS1 ADD DATAFILE ’data1.dat’ EXTENT_SIZE 8M INITIAL_SIZE 2G ENGINE NDBCLUSTER; ALTER TABLESPACE TS1 ADD DATAFILE ’data2.dat’ INITIAL_SIZE 4G ENGINE NDBCLUSTER; 

This tablespace is created when the data nodes are started with --initial , and can be used whenever creating NDB Cluster Disk Data tables thereafter. 

• Disk Data latency parameters.  The two parameters listed here can be used to improve handling of latency issues with NDB Cluster Disk Data tables. 

