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Support

Usage Note 35858: SAS® support for EAV on the z/OS operating system

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SAS changes that support EAV features were first made available with SAS 9.2 maintenance releases in November 2009. Support is available for all EAV features in SAS 9.3. For earlier releases, support is available as described below. See the Glossary at the end of this SAS note for a definition of the terms used here.

Summary of EAV features provided by z/OS

  • z/OS V1R10: Initial EAV support. VSAM data sets can reside in EAS.
  • z/OS V1R11: Extended-format sequential data sets can reside in EAS.
  • z/OS V1R12: All other non-VSAM data sets can reside in EAS.
    The V1R12 support can be added to a V1R11 system via maintenance.

SAS support for EAV is provided in two releases of SAS

  • SAS 9.2M2 (the second maintenance release of SAS 9.2, available November 2009) supports features that are available in z/OS V1R10 as well as features that are available in the initial release of z/OS V1R11. It also supports many of the features that were added in z/OS V1R12. (See the support matrix, below.)
  • SAS 9.3(available July 2011)supports all EAV features.

General considerations for SAS support

  • Access to VSAM data sets that reside on an EAV is available for all supported SAS releases. (IBM support for EAV does not require any code changes in SAS for VSAM data sets.)
  • Access to a non-VSAM data set that resides on an EAV without extended attributes is supported the same way it is for traditional volumes. (These data sets must reside in the track-allocated space.)
  • Access to a non-VSAM data set that has extended attributes requires at least SAS 9.2M2, and it might require SAS 9.3. Extended attributes are required if the data set resides in EAS but might be present for

Note: At this time EAV is not supported for the load module libraries that are used in a CLIST or REXX exec for interactive SAS sessions. A fix is under consideration for a future release.


Support Matrix for Support of EAV Features, by SAS Release

The following table provides additional detail on the support provided by SAS. The SAS companion for each particular release also has details of this support. This chart refers only to data sets that reside in EAS or that have extended attributes. Traditional non-VSAM data sets that do not have extended attributes are supported by all SAS releases just as they are on traditional volumes.
SAS Release z/OS V1R10 and Initial V1R11 z/OS V1R12 (and V1R11 Systems with Additional EAV Maintenance)
Prior to 9.2M2 Capabilities:

  • Processing VSAM data sets (whether or not they reside in the EAS). This includes SAS bound libraries that reside in a VSAM linear data set.
  • Processing UNIX files in a zFS that resides in EAS.

Limitations:

  • The VTOC Access Method cannot process EAVs.
  • The DSINFO window cannot display information about data sets with extended attributes.

Limitations (related to features that were new in z/OS V1R12):

  • SAS cannot process non-VSAM data sets that have extended attributes.














9.2M2 and 9.2M3 Capabilities:

Same as prior releases but with the following additions:

  • Support for extended sequential data sets residing in EAS. This includes external file processing (FILENAME, FILE, and INFILE statements) as well as sequential access bound libraries on disk.
  • Support for VTOC Access method on EAV volumes.
  • DSINFO window supports data sets with extended attributes
Limitations:
  • The EATTR option is not available on the LIBNAME and FILENAME statements.


Capabilities:

In addition to the support that was available with z/OS V1R11, SAS 9.2M2 and SAS 9.2M3 can process the additional non-VSAM data sets that can reside in EAS.

Limitations (related to features that were new in z/OS V1R12):

  • SAS cannot process direct access-bound libraries that reside in EAS.
  • PROC PDS cannot empty a PDS with extended attributes.
  • PROC RELEASE cannot process data sets with extended attributes.
  • SAS abends if you attempt to access V5 bound libraries (DSORG=DA) in EAS-eligible data sets. (This situation is unlikely to occur.) However, V5 libraries can be processed if they are copied to a non-EAS eligible data set.
SAS 9.3 Capabilities:

Same as prior SAS releases with the addition of support for the EATTR option on the FILENAME and LIBNAME statements.








Capabilities:

Limitations present in SAS 9.2M2 and SAS 9.2M3 have been removed:

  • SAS can process direct access bound libraries that reside in EAS.
  • PROC PDS and PROC RELEASE support data sets with extended attributes.
  • SAS produces an error message when attempting to access SAS Version 5 bound libraries (DSORG=DA) in EAS-eligible data sets.

Glossary

Term Definition
EAS Acronym for extended addressing space. The EAS is the set of locations on an EAV for which the cylinder address is >= 65,536 (0x10000).
EAS-eligible data sets This term applies to the types of data sets that are eligible to reside in the extended addressing space (EAS) of an extended address volume (EAV). Which types of data sets are eligible depends on the release of z/OS.
EAV Acronym for extended address volume. An EAV is a volume with more than 65,520 (0xFFF0) cylinders. Before the introduction of EAV support in z/OS V1R10, all direct access storage device (DASD) volumes supported on z/OS used a 16-bit value to address cylinders on the device. EAVs use a 16-bit address for cylinders 1-65520 and a 28-bit cylinder address for cylinders in the EAS (defined below).
extended attributes This refers to a data set created with format 8/9 DSCBs in the VTOC. These new format DSCBs provide room for additional information about a data set and use 28-bit cylinder addresses to enable support for data sets having DASD extents in EAS. Important: A data set can have extended attributes without residing in EAS. In order for a data set to have extended attributes, it must be EAS-eligible and must be created with EATTR=OPT on an EAV.
extended-format sequential data set A sequential, non-VSAM data set that was allocated with DSNTYPE=EXTREQ or DSNTYPE=EXTPREF specified in the JCL (or equivalent options in an SMS data class). Extended-format sequential data sets are processed like ordinary sequential data sets, but the system controls the low-level format of the data set and provides additional capabilities such as striping, compression, an unlimited number of tracks per volume, etc.
Note: This concept is completely separate and distinct from “extended attributes” (see entry in glossary). Extended-format sequential data sets may or may not have extended attributes. In addition, other types of data sets also may or may not have extended attributes.
track-allocated space Space in EAS is always allocated in multicylinder units. Track-allocated space refers to the range of cylinder addresses that can be represented in 16 bits; that is, 65,535 or lower. This range of addresses below the EAS exists to provide compatibility with older programs that do not support data sets that have extended attributes. (See definition below.) In some documentation, this is called “base Addressing space."
VTOC volume table of contents

To summarize:

  • VSAM data sets that are allocated on an EAV have extended attributes by default.
  • Non-VSAM data sets that reside in EAS must have extended attributes.
  • Other non-VSAM data sets on an EAV might have the extended attributes.
  • z/OS V1R11 is the first release that enables non-VSAM data sets to have extended attributes and is thus the minimum level of z/OS required to place non-VSAM data sets in EAS.


Operating System and Release Information

Product FamilyProductSystemSAS Release
ReportedFixed*
SAS SystemBase SASz/OS8.2 TS2M0
* For software releases that are not yet generally available, the Fixed Release is the software release in which the problem is planned to be fixed.