Display IAM information

Information displays for any type of data set can be requested from the VSAM utility screen (VSAM Utility Screen) by entering a data set name and pressing Enter or by placing an S next to the data set name in a data set selection list.

When you press Enter, File-AID displays the IAM Information screen as shown in the following figure. On smaller screens, this panel is scrollable.

FILE-AID -------------- IAM Dataset Information ----------------------------
COMMAND ===>                                                 SCROLL ===> PAGE

CATALOG CATALOG.MVSICFU.V01KTOR
CLUSTER 'USERID0.$IAM.TEST'                             VOUME SERIAL PRD511
DATA    'USERID0.$IAM.TEST.DATA'

GENERAL DATA:                                  CURRENT ALLOCATION OPTIONS:
   DEVICE TYPE:                      3390         REUSE OPTION:          NO
   FILE TYPE:                        KSDS   EXT   SHARE OPTION:           1
   AVERAGE RECORD SIZE:                10         RELEASE:
   MAXIMUM RECORD SIZE:               100         DATA COMPRESS:         NO
   KEY LENGTH:                          5         EATTR:                OPT
   KEY LOCATION:                        0         BLOCKING FACTOR:        4
                                                  % INTEGRATED OVERFLOW: 0

DATASETS RELATED TO ENTRY 'USERID0.$IAM.TEST'
   TYPE        DATASET NAME
   CLUSTER   - USERID0.$IAM.TEST

DATE INFORMATION:                              SMS INFORMATION:
   CREATION DATE:            23/05/2022           OWNER ID:            $IAM
   EXPIRATION DATE:                               STORAGE CLASS:   STDDODFW
   MODIFICATION DATE:        23/05/2022           DATA CLASS:      STRIPEAV
   MODIFICATION TIME:                    GMT      MANAGEMENT CLASS QCTEST@S

ENCRYPTION INFORMATION:
   KEYLABEL SYS2.CPWR.CRYPTO.LABEL

SPACE ALLOCATION INFORMATION:                  DATA RECORDS:
   UNIT:            CYLINDERS                     TOTAL:
   PRIMARY:                50                     DELETED:                0
   SECONDARY:              50                     INSERTED:               0
   ALLOCATED TRACKS:      945                     UPDATED:                0
   USED TRACKS:             0 ( 0%)             RETRIEVED:              0
   ALLOCATED EXTENTS:       1                     OVERFLOW:               0
   USED EXTENTS:            1 (100%)

VOLUME INFORMATION:                            OVERFLOW BLKS:            0
   PHYS BLKSIZE:        10240                   PE BLOCKS:                0
   PHYS BLKS/TRK:           0                   EXT BLOCKS USED:          0
   HURBN:                   0                   EXT ALLOC:                0
   HARBN:                   0                   EXT BLOCKS AVAILABLE:     0
   HURBA:                   0
   HARBA:                 512


CURRENT ORGANIZATION INFORMATION:
   SIMULATED CISZ:       8192
   NUMBER OF CIS/CA:       37
   FREESPACE CA%:           0

IAM ALLOCATION INFORMATION:
   DATASET NAME TYPE: LINEAR                     BACKUPCOMPRESSED:
   JOURNALING:           NONE                     ENHANCED:             YES
   MULTI-VOL OVRD:    PRIMARY                     PRIME RELATED OVRFLW: YES
   PRIME EXTENSION:                               PSEUDO RBA:
   MAX # OF BUFFERS:                              VAR RECS IN OVRFLW:   YES
   MIN # OF BUFFERS:                              EXTENDED ESDS:
   DICTIONARY:                                    SECONDARY MULT FACTOR: 50

RLS INFORMATION:
   RLS IN USE:                         NO
   LOGREPLICATE:                       NO
   LOG:                              NONE
   FRLOG (BATCH LOGGING):            NULL
   RLSID:
   LOGSTREAMID:

******************************* BOTTOM OF DATA *******************************

The following table describes the fields on the IAM Dataset Information panel:

Field	Description
CATALOG	Catalog name.
CLUSTER	Fully qualified name of the IAM cluster.
DATA	Data component name.
VOLUME SERIAL	Name of the device on which data is stored.
GENERAL DATA
DEVICE TYPE	Type of device on which data is stored (for example: 3380 and 3390).
FILE TYPE	Type of VSAM cluster organization: KSDS, KSDS EXTENDED, KSDS LARGE, KSDS BASIC, ESDS, RRDS, AIX, and VRRDS.
AVERAGE RECORD SIZE	Estimated average size of data record specified at allocation.
MAXIMUM RECORD SIZE	Largest possible data record that the data set can contain.
KEY LENGTH	Length of the field within each record that contains key information. This is the length of the prime key for base clusters and the length of the alternate key for alternate indexes.
KEY LOCATION	The relative position of the prime record key for KSDS base clusters or the relative position of the alternate key in the base cluster for alternate indexes.
CURRENT ALLOCATION OPTIONS
REUSE OPTION	Specifies whether the data set is reusable (can be reloaded).
SHARE OPTION	Specifies the amount of sharing among regions-systems. The first number displayed is the region share option: 1—The data set can be shared by any number of users for read processing. VSAM ensures data integrity. 2—The data set can be shared by any number of users for read processing and can be accessed by one user for processing. ENQ/DEQ required for read integrity. 3—The data set can be shared by any number of users. Each user is responsible for integrity. 4—The data set can be shared by any number of users and the buffers used for direct processing are refreshed for each request.
RELEASE	Specifies the space release option as either YES or NO.
DATA COMPRESS	Specifies the Data compress option
EATTR	Specifies the following options: NO—The data set cannot have extended attributes. OPT—Extended attributes are optional for the data set.
BLOCKING FACTOR	Specifies the blocking factor.
%INTEGRATED OVERFLOW	Specifies the %integrated overflow.
DATASETS RELATED TO ENTRY	Fully qualified name of the VSAM data set listing the TYPE and DATASET NAME.
DATE INFORMATION
CREATION DATE	The date the data set was allocated.
EXPIRATION DATE	The date the data set is to expire.
MODIFICATION DATE	The date the data set was last updated.
MODIFICATION TIME	The time the data set was last updated (This is Greenwich Mean Time).
SMS INFORMATION
OWNER ID	The ID of the data set owner.
STORAGE CLASS	The SMS Storage Class to be used to allocate the data set. The Storage Class is used to describe the hardware requirements of the data set.
DATA CLASS	The SMS Data Class to be used to allocate the data set. The Data Class is used to describe the attributes of the data set such as RECFM, DSORG, LRECL, and BLKSIZE.
MANAGEMENT CLASS	The SMS Management Class to be used to allocate the data set. The Management Class is used to describe the retention and migration backup for the data set.
ENCRYPTION INFORMATION
KEYLABEL	(z/OS 2.3 and up) Identifies the name, up to 64 bytes, of the key label used to encrypt the data set.
SPACE ALLOCATION INFORMATION
UNIT, PRIMARY, SECONDARY	Allocated area by UNIT type for data showing initial primary space and amount for secondary.
ALLOCATED TRACKS	The amount of space allocated in tracks.
USED TRACKS	The number of tracks and percent of data space used.
ALLOCATED EXTENTS	The number of extents allocated.
USED EXTENTS	The number of extents and the percent of extents used.
DATA RECORDS
TOTAL	The number of records in the prime data area.
DELETED	The number of records deleted.
INSERTED	The number of records inserted.
UPDATED	The number of records updated.
RETRIEVED	The number of records retrieved from the data set since the last reorganization.
OVERFLOW	The number of records overflowed.
VOLUME INFORMATION
PHYS BLKSIZE	Size of each block written in a control area.
PHYS BLKS/TRK	The number of blocks per track.
HURBN	This the highest used block number currently in the IAM file.
HARBN	This the highest allocated block number currently in the IAM file.
HURBA	This the highest used RBA currently in the IAM file.
HARBA	This the highest allocated RBA currently in the IAM file.
OVERFLOW BLKS	The number of overflow blocks.
PE BLOCKS	The number of prime extension blocks.
EXT BLOCKS USED	The number of extended blocks used.
EXT ALLOC	The number of allocated extended blocks.
EXT BLOCKS AVAILABLE	The number of available extended blocks.
CURRENT ORGANIZATION INFORMATION
SIMULATED CISZ	The simulated CI size in the organization.
NUMBER OF CIS/CA	The number of control intervals in each control area.
FREESPACE CA%	The percentage of free space in control area.
IAM ALLOCATION INFORMATION
DATASET NAME TYPE	Specifies the below external IAM data set format on DASD: BASIC—Indicates a standard Physical Sequential data set. LARGE—Indicates an MVS Large Format Sequential data set. EXTENDED—Indicates a DFSMS Extended Format data set. LINEAR—Indicates an Encrypted Linear data set.
JOURNALING	For Enhanced format data sets, specifies the below IAM journaling capabilities: BOTH or ALL—IAM log data set includes both before and after images. BEFORE—IAM log data set includes before (undo) images. AFTER—IAM log data set includes after (redo) images. NONE—IAM journaling is not used for this data set.
MULTI-VOL OVRD	Specifies whether IAM uses the PRIMARY or SECONDARY space allocation value when anticipating a new extent on another DASD volume.
PRIME EXTENSION	Indicates the number of Prime Extension (PE) blocks allocated for this data set.
MAX # OF BUFFERS	Indicates the maximum number of buffers used during file access for this data set.
MIN # OF BUFFERS	Indicates the minimum number of buffers used during file access for this data set.
DICTIONARY	Specifies the four-character suffix of the user-provided hardware compression dictionary. The dictionary is a load module, starting with 'IAMD'.
BACKUPCOMPRESSED	Indicates whether the input data is in IAM Data Compressed format.
ENHANCED	Indicates an Enhanced format IAM data set.
PRIME RELATED OVRFLW	Specifies whether IAM uses the Prime Related Overflow structure for this data set.
PSEUDO RBA	Indicates that an IAM ESDS data set can exceed 4 gigabytes in size by using non-standard 4-byte RBAs (Relative Byte Addresses).
VAR RECS IN OVRFLW	For Enhanced format data sets, it implies that IAM can use true variable-length records in the Extended Overflow area.
EXTENDED ESDS	Specifies the use of an 8-byte RBA value for ESDS data sets to exceed 4 gigabytes of user data.
SECONDARY MULT FACTOR	Specifies the multiplication factor for the secondary quantity when the data set exceeds five extents on a volume.
RLS INFORMATION
RLS IN USE	Indicates if RLS is being used for this data set.
LOGREPLICATE	Specifies if the data set is eligible for VSAM replication.
LOG	Indicates the below recoverability options for the data set: NONE—Declares the data set as non-recoverable. UNDO—Declares the data set as backward recoverable. REDO—Declares the data set as forward recoverable. ALL—Declares the data set as both backward and forward recoverable.
FRLOG (BATCH LOGGING)	Specifies the below batch logging options: NONE—Indicates the data set is available for VSAM batch logging but the function is disabled. UNDO—Allows changes to the data set to be backed out using VSAM logging. REDO—Allows changes to the data set to be forward recovered using VSAM logging. ALL—Enables both backing out and forward recovery of changes made to the data set using VSAM logging.
RLSID	If displayed, specifies the four-character identifier of the preferred IAM RLS address space for this data set.
LOGSTREAMID	Specifies the name of the forward recovery log stream.

Display IAM information

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