BL_CPU_PARALLELISM= Data Set Option

Specifies the number of processes or threads to use when building table objects.

Valid in:	DATA and PROC steps (when accessing DBMS data using SAS/ACCESS software)
Default:	none
Requirement:	To specify this option, you must first set BULKLOAD=YES.
Data source:	DB2 under UNIX and PC Hosts
See:	BL_DATA_BUFFER_SIZE= data set option, BL_DISK_PARALLELISM= data set option, BULKLOAD= data set option

Syntax

Details

Syntax

BL_CPU_PARALLELISM=number of processes or threads

Syntax Description

number of processes or threads: specifies the number of processes or threads that the load utility uses to parse, convert, and format data records when building table objects.

Details

This option exploits intrapartition parallelism and significantly improves load performance. It is particularly useful when loading presorted data, because record order in the source data is preserved.

The maximum allowable number is 30. If the value is 0 or has not been specified, the load utility selects an intelligent default. This default is based on the number of available CPUs on the system at run time. If there is insufficient memory to support the specified value, the utility adjusts the value.

When BL_CPU_PARALLELISM is greater than 1, the flushing operations are asynchronous, permitting the loader to exploit the CPU. If tables include either LOB or LONG VARCHAR data, parallelism is not supported and the value is set to 1—regardless of the number of system CPUs or the specified value.

Although use of this parameter is not restricted to symmetric multiprocessor (SMP) hardware, you might not obtain any discernible performance benefit from using it in non-SMP environments.

For more information about using BL_CPU_PARALLELISM=, see the CPU_PARALLELISM parameter in the IBM DB2 Universal Database Data Movement Utilities Guide and Reference.