Data Set Options for Relational Databases

BL_DATA_BUFFER_SIZE= Data Set Option

Specifies the total amount of memory to allocate for the bulk load utility to use as a buffer for transferring data.

Default value:	none
Valid in:	DATA and PROC steps (when accessing DBMS data using SAS/ACCESS software)
DBMS support:	DB2 under UNIX and PC Hosts

Syntax
Syntax Description
Details
See Also

Syntax

BL_DATA_BUFFER_SIZE=buffer-size

Syntax Description

buffer-size: specifies the total amount of memory (in 4KB pages)--regardless of the degree of parallelism--that is allocated for the bulk load utility to use as buffered space for transferring data within the utility.

Details

To specify this option, you must first set BULKLOAD=YES.

If you specify a value that is less than the algorithmic minimum, the minimum required resource is used and no warning is returned. This memory is allocated directly from the utility heap, the size of which you can modify through the util_heap_sz database configuration parameter. If you do not specify a valued, the utility calculates an intelligent default at run time that is based on a percentage of the free space that is available in the utility heap at the time of instantiation of the loader, as well as some characteristics of the table.

It is recommended that the buffer be several extents in size. An extent is the unit of movement for data within DB2, and the extent size can be one or more 4KB pages. The DATA BUFFER parameter is useful when you are working with large objects (LOBs) because it reduces I/O waiting time. The data buffer is allocated from the utility heap. Depending on the amount of storage available on your system, you should consider allocating more memory for use by the DB2 utilities. You can modify the database configuration parameter util_heap_sz accordingly. The default value for the Utility Heap Size configuration parameter is 5000 4KB pages. Because load is only one of several utilities that use memory from the utility heap, it is recommended that no more than 50% of the pages defined by this parameter be made available for the load utility, and that the utility heap be defined large enough.