Data Set Options for Relational Databases |
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
|
BL_DATA_BUFFER_SIZE=buffer-size
|
- 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.
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.
For more information about using this option, see the DATA BUFFER parameter
in the IBM DB2 Universal Database Data Movement Utilities Guide and
Reference.
BL_CPU_PARALLELISM= Data Set Option
BL_DISK_PARALLELISM= Data Set Option
BULKLOAD= Data Set Option
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