5665-327 IBM Data Facility Data Set Services (DFDSS)
IBM U.S. Sales Manual
Revised: March 17, 1998.
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|IBM U.S. Product Life Cycle Dates|
|Program Number||VRM||Announced||Available||Marketing Withdrawn||Service Discontinued||Replaced By|
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(For IBM US, No Longer Available as of December 29, 1997)
(For IBM US, Program Services Discontinued as of June 30, 1999)
IBM Data Facility Data Set Services Version 2 Release 5 (DFDSS 2.5.0) is an ideal tool for high-speed data movement, and supports the IBM 3480 Magnetic Tape Subsystem improved data recording capability. It supports partitioned data set extended (PDSE), and is a high-performance data mover for IBM Data Facility Hierarchical Storage Manager Version 2 Release 5 (DFHSM 2.5.0). DFDSS is an important part of Data Facility Storage Management Subsystem (DFSMS(TM)).
DFDSS 2.5.0 contains performance improvements and additional
enhancements which allow for more efficient use of DASD storage, improved
security with RACF during restore, and virtual storage constraint relief.
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DFDSS 2.5 is an integral part of DFSMS. It is the high-speed data
mover and primary conversion vehicle to the DFSMS environment. It is an
ideal tool for the migration of data to IBM DASD products. It provides
backup and recovery, space management, and data movement for conversion
to IBM DASD. Also, DFDSS can now be the primary data mover for DFHSM
Version 2 Release 5, providing improved performance (for large data sets)
for migration and backup tasks, as well as providing additional data set
support for DFHSM.
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- Supports 3480 improved data recording capability
- Supports PDSE
- High-performance data mover for DFHSM 2.5.0
- Performance improvements and additional enhancements.
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3480 Improved Data Recording Capability Feature Support
DFDSS 2.5.0 supports the Improved Data Recording Capability feature of IBM 3480 Tape Magnetic Tape Subsystem. The combination of IBM 3480 Improved Data Recording Capability, DFDSS 2.5.0, and DFHSM 2.5.0 provides faster and more efficient DASD dump/restore operations. Support for IBM 3480 Improved Data Recording Capability is also available in DFDSS Version 2 Release 4 with APAR PL43470.
IBM 3480 Improved Data Recording Capability increases the effective cartridge capacity by up to five times as well as the effective performance by up to 70 percent.
DFDSS 2.5.0 expands its role in the system-manage storage environment with DFSMS by supporting all PDSE data movement functions. MVS/DFP Version 3 Release 2 provides a new data set type, PDSE, which eliminates many data and space management problems associated with PDS; for example, a PDSE data set need not be compressed to make allocated but unused space available.
Conversion Tool Between PDS and PDSE
DFDSS 2.5.0 provides an efficient tool to convert from PDS to PDSE, or from PDSE to PDS while copying a data set. The interactive panels have been enhanced to support new keywords which allow the user to perform these conversions.
Data Mover for DFHSM 2.5.0
DFDSS 2.5.0 provides additional function which enhances DFDSS and DFHSM interaction. This function, added for logical copy and dump/restore operations, allows DFHSM 2.5.0 to use DFDSS 2.5.0 as a logical data set mover; that is, DFHSM 2.5.0 provides an option to use DFDSS 2.5.0 as its data set mover for all of its space and availability DASD management functions. This should improve performance of DFHSM data movement operations. DFHSM 2.5.0 uses DFDSS 2.5.0 for supporting PDSE and multivolume non-VSAM data sets. DFHSM 2.5.0's aggregate backup and recovery support (ABARS) invokes DFDSS 2.5.0 logical dump and restore.
Improved Performance in Processing VSAM Data Sets
Significant performance improvements have been made in logical dataset dump of VSAM data sets, particularly when a large number of VSAM datasets reside on a volume. This enhancement also applies to data set copy and volume conversion between system-managed and non-system-managed storage. CPU time, elapsed time and I/O activities to the VVDS have been reduced substantially. This support is also available in DFDSS Version 2 Release 4 with APAR# PL36660 and PL48099.
Dump with Compress and Optimize
The keywords compress and optimize may now be specified in the same dump control statement. Compress allows significant reduction in media storage, while Optimize allows significant reduction in the number of I/O operations. For physical volume dumps using compress and optimize with option 4, elapsed time is approximately one-third less and processor time is approximately one-half as compared to DFDSS 2.4 with compress.
Stand-Alone Restore Improvement
Tapes that were made by the dump compress option can now be restored by stand-alone restore. This function is also available in DFDSS Version 2 Release 4 with APAR PL47358
Generation Data Set Copy and Restore Improvement
Users can specify the target status (deferred, active, or roll-off) of a DFSMS generation data set for DFDSS copy or restore operations.
More Efficient Use of DASD Storage
The print command has been enhanced to allow multiple logical records in a physical block for more efficient use of storage. The user can declare a larger block size for SYSPRINT data set or the output data set of the print command.
Improved Security with RACF During Restore
DFDSS Version 2 Release 4 checks the authorization during restore operation only when restoring to an existing data set. DFDSS 2.5.0 checks the authorization even if the data set does not exist at restore time ensuring that the user is authorized to read the data set on the dump tape and create the target data set on the DASD.
Expanded Data Set Support
The copy and restore commands now process the undefined data set organization (DSORG) and system data sets. The release command may be used for releasing allocated but unused space from system data sets. System data sets may be deleted using the dump command.
Virtual Storage Constraint Relief (VSCR)
DFDSS 2.5.0 relieves virtual storage constraints by moving DFDSS
internal control blocks above the 16MB line, allowing DFDSS 2.5.0 to
process more data sets per invocation. This enhancement is also
available in DFDSS Version 2 Release 4 with APAR PL35096.
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|Operating Environment||Hardware Requirements||Software Requirements|
DFDSS Version 2 Release 5 is designed to operate on any IBM processor that is supported by MVS/System Product (MVS/SP (TM)) Version 1, Version 2 or Version 3.
- Host System Requirements
DFDSS Version 2 Release 5 executes in an MVS host system environment under:
- MVS/DFP (TM) Version 3 Release 1 (5665-XA3) and its corequisite MVS/SP products
- MVS/XA (TM) DFP Version 2 Release 1 (5665-XA2) and its corequisite MVS/SP products
- MVS/370 (TM) Data Facility Product (DFP) Version 1 Release 1 (5665-295) and its corequisite MVS/SP products
and any subsequent releases of these system control programs unless otherwise indicated.
- Interactive Storage Management Facility (ISMF) Requirements
To use ISMF to generate the DFDSS commands interactively, the following IBM licensed programs are required:
- MVS/XA DFP Version 2 Release 2 or MVS/DFP Version 3 Release 1
- Interactive System Productivity Facility (ISPF) Version 2 Release 3 (5665-319)
- ISPF/Program Development Facility (PDF) Version 2 Release 3 (5665-317) with APAR or ISPF/PDF Version 3 Release 1
- TSO/Extended (E) Release 2 (5665-285) or TSO/E Version 2 (5685-025)
and any subsequent releases of these IBM licensed programs unless otherwise indicated.
For ISMF volume application support, both DFDSS Version 2 Release 3 and MVS/XA DFP Version 2 Release 3, or their subsequent releases are required.
- Other Requirements
- DFDSS Version 2 Release 5 requires MVS/DFP Version 3 for DFSMS support and MVS/DFP Version 3 Release 2 for PDSE support
- IBM 3480 tape with Improved Data Recording Capability feature requires MVS/DFP 3.2, MVS/DFP 3.1.1, or MVS/XA DFP 2.4.0.
- DFSMS is not supported by DFDSS versions and releases prior to DFDSS Version 2 Release 4
- Resource Access Control Facility (RACF) Version 1 Release 8.1 (5740-XXH) or subsequent releases may be used to provide access authorization in DFSMS.
Virtual Storage Consideration
DFDSS 2.5.0 relieves the virtual storage constraints by moving the
DFDSS internal control blocks above the 16MB line. However, DFDSS 2.5.0
load modules increase the usage of virtual storage below the 16MB line by
100KB. This increase is due to growth of the DFDSS load modules for the
new functions of DFDSS 2.5.0.
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DFDSS Version 2 Release 5 is the functional replacement of DFDSS Version 2 Release 4.
Performance information may be available prior to general
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The following licensed material will be available from IBM at product availability. To order, contact your IBM marketing representative.
The first copy is supplied automatically with the basic machine- readable material. Use the 8885 feature number to order additional copies for a fee.
LY27-9538 DFDSS Diagnosis Guide (Additional Copy Feature Number 8885)
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|Security, Auditability, and Control|
This program uses the security and auditability features of the host software. User management is responsible for evaluation, selection, and implementation of security features, administrative procedures, and appropriate controls in application systems and communication facilities.
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