Allocate IAM

The Allocate cluster function allocates IAM data sets. To indicate File-AID that an IAM file, specify $IAM on the Allocate New VSAM Cluster screen File-AID that the file is IAM. Specify $IAM as at least one of the following:

Part of the data set name
Owner ID
SMS Data Class or Storage Class.

The Allocate IAM function is used to allocate new IAM data sets online or in batch.

File-AID ------------ Allocate IAM Dataset ---------------------
COMMAND ===>


Component names:
Cluster:                 'USERID0.$IAM.TEST'
Data component      ===> 'USERID0.$IAM.TEST.DATA'
Dataset type        ===> R         (K=KSDS; E=ESDS; R=RRDS)
Dataset Name Type   ===>           (L=Large; E=Extended;
                                     B=Basic; Blank=Default)
Specify SMS Class Information:
Storage             ===>
Data                ===>
Management          ===>

Space Allocation:
Volume serial                   ===> PRD908
Units                           ===> CYLS
Primary                         ===> 50
Secondary                       ===> 50

Key length                      ===> 0         (0-249)

Key position                    ===> 0         (0-max)
Average Recordsize              ===> 198
Maximum Recordsize              ===> 1972
Control Interval Size           ===> 8192
Minimum Number of Buffers       ===>           (1-32760)
Maximum Number of Buffers       ===>           (1-32760)
CA Percent Free                 ===> 0

IAM Allocation Options:
Backup Compressed       ===>         (blank=default; Y=Yes; N=No)
Blocking Factor         ===>         (blank=default; 1-15; 300-32760)
Create Buffer Option    ===>         (BSAM; CYL; MCYL; MTRK; TRK; 64BIT)
Data Compression        ===>         (blank=default; YES; NO; HW; HWE; SW)
Dictionary              ===>         (Hardware Compression Dictionary)
Enhanced                ===>         (blank=default; Y=Yes)
HPF                     ===>         (blank=default; Y=Yes; N=No)
Index Compressed        ===>         (blank=default; Y=Yes; N=No; L=Long)
Integrated              ===>         (CI % free space)
Journaling              ===>         (Both; All; Before; After; None)
Limit Keys              ===>         (blank=default; 3-64)
Multi-Volume Override   ===>         (blank=default; P=Primary; S=Secondary)
Pagefix                 ===>         (blank=default; Y=Yes)
Prime Extension         ===>         (blank=default; 0-32767)
Prime Related Overflow ===>         (blank=default; Y=Yes; N=No)
Secondary Multi Factor ===>         (blank=default; 0-25)
Release Space           ===>         (blank=default; Y=Yes; N=No)
RLSID                   ===>         (* = RLSID with No Operand;
                                       cccc = RLSID=cccc Address Space)
RRDSLOAD                ===>         (blank=default; Sequential; Random)
Variable Records in                  (Enhanced Format Only
  Overflow               ===>          blank=default; Y=Yes; N=No)
PSEUDO RBA              ===>         (ESDS Only, blank=default; Y=Yes)
Extended ESDS           ===>         (ESDS Only, blank=default; Y=Yes; N=No)

Allocation Options:
Expiration date         ===>            (YYYY/MM/DD or blank)
Reusable                ===> NO      (Y=Yes; N=No)
Share Option            ===> 1       (1; 2; 3; 4)
  Extended Attributes     ===>         (EATTR: O=Opt; N=No)
  Spanned records         ===> NO      (Y=Yes; N=No)
  LOGREPLICATE            ===>            (L=LOGREPLICATE; N=NOLOGREPLICATE)
  LOG                     ===> N       (N=NONE; U=UNDO; A=ALL)
  LOGSTREAMID
  (Fully Qualified Name) ===>
  Encryption:
  Keylabel   (Name of the Key Label to be used for encryption)
  ===>
  FRLOG (Batch Logging)   ===>            (N=NONE; U=UNDO; R=REDO; A=ALL)

Multiple Volumes         ===> NO      (Y=YES; N=NO)

Use ENTER to Allocate Dataset, END to cancel request

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

Field	Description
Component names
Cluster	Fully qualified name of the new IAM cluster is displayed for verification. If you enter an unqualified name on the VSAM utility screen, a File-AID IAM cluster name is constructed.
Data component	Data component data set name generated by File-AID. This field is modifiable.
Dataset type	Specify the type of IAM data set for the allocation KSDS, ESDS, or RRDS.
Dataset Name Type	Specifies the type of dataset to be used for the IAM file. Valid values are: LARGE—The IAM data set uses the Large Format Sequential data set type EXT—The IAM data set uses the SMS extended format BASIC—The IAM data set is a basic non-VSAM data set
Specify SMS Class Information
Storage	Specify the SMS storage class to use for the allocation of the data set. The storage class describes the hardware requirements of the data set.
Data	Specify the SMS data class to use for the allocation of the data set. The data class describes the attributes of the data set, such as RECORG, KEYLEN, KEYOFF, and SPACE.
Management	Specify the SMS management class to use for the allocation of the data set. The management class describes the migration, backup, and retention for the data set.
Space Allocation
Volume serial	Specify the volume serial of the direct access device that contains the data set. When using SMS and allocating a non-SMS managed data set, a Volume serial is required.
Units	Specify one of the following storage unit types depending on how the data set size is expressed: TRKS—Tracks CYLS—Cylinders RECS—Records K—Kilobytes M—Megabytes If the RECS value is specified, File-AID uses the value specified in the Average Recordsize field for the unit quantity.
Primary	Specify the primary allocation quantity as specified in the space units field.
Secondary	Specify the secondary allocation quantity as specified in the space units field.
Key length	For keyed data sets, specify a value. For IAM KSDS clusters, this value must be between 1 and 249. For IAM RRDS clusters, any number between 0 to 249 is valid. Otherwise the value should be zero.
Key position	For keyed data sets, specify a value. For IAM KSDS clusters, the relative position of the key field. Any number from 0 through record length-1 is valid. For IAM RRDS, if the key length is zero, then key position must also be zero, otherwise same as for IAM KSDS.
Average Recordsize	Specify a value, in bytes, for the average record length to be stored in the cluster. If the records are of fixed length, the average and maximum should be the same.
Maximum Recordsize	Specify a value for variable length records. This is the length of the longest record expected in the cluster.
Control Interval Size	Specify a number (from 0 to 100) representing the percentage of space free in a control interval for processing. If this is omitted, 0 is assumed.
Minimum Number of Buffers	Specify the minimum number of buffers that IAM is maintained during file processing.
Maximum number of buffers	Specify the maximum number of buffers that IAM is acquired during file processing.
CA Percent Free	Specify a numeric value. This is especially useful for data-compressed ESDS data sets.
IAM Allocation Options
Backup Compressed	Specifies that the input data is in IAM Data Compressed format. The Backup Compressed option is only valid for IAM software compressed data sets.
Blocking Factor	Specifies the block factor (from 1 to 15) or block size of the IAM data set. The default value is based on the specified CI size and maximum record size.
Create Buffer Option	Specifies the buffering option to be used for the file load. Because the file load is essentially a sequential output process, the buffering is different than the normal IAM Real Time Tuning Buffering. The values that can be specified are: BSAM—Use the BSAM Access Method macros to load the file CYL—Buffers for one cylinder worth of blocks are acquired. Approximately half a cylinder is written per I/O MCYL—Buffers for two cylinders worth of blocks are acquired. One cylinder is written per I/O MTRK—Buffers for ten tracks are acquired. Five are written per I/O TRK—Buffers for two tracks are acquired. One track is written per I/O 64BIT—Same buffering as MCYL except that 64-bit virtual storage is used for the buffers The default value is MCYL, or as specified in the IAM Global Options Table.
Data Compression	Indicates IAM to compress the data. Valid values are: YES—Specifies that the dataset will have its data compressed, using the default data compression technique from the IAM Global Options Table NO—Specifies that no compressed data is used for this data set HW—Specifies that IAM should use the z/OS hardware compression instruction to compress the data HWE—Specifies that IAM should utilize an enhanced dictionary build process that increases the amount of potential data strings that are eligible for compression SW—Specifies that IAM should use its standard software compression algorithm with no dictionaries are used with this form of compression.
Dictionary	Specifies the four-character suffix for the name of the user-provided hardware compression dictionary. By default, IAM creates a dictionary during the file load process by using data from the initial records written.
Enhanced	Specifies IAM to create an Enhanced format IAM data set. This type of data set uses a dynamic overflow area that acquires additional DASD extents during file updates, as needed.
HPF	Specify whether or not IAM uses z/HPF architecture on devices that are capable of utilizing that function. Default is YES that z/HPF will be used unless otherwise specified in the IAM Global Options Table.
Index compressed	Specifies whether or not the file is eligible for a compressed index. Valid values are YES, LONG or NO.
Integrated	Specifies CI% free space. This is especially useful for data-compressed ESDS data sets.
Journaling	For Enhanced format files, specifies the IAM journaling capabilities to be used. Valid values are: BOTH or ALL—The IAM log data set contains both the before (undo) and after (redo) images of updated records. This enables you to perform either a forward recovery or a backward (backout) recovery BEFORE—The IAM log data set contains the before (undo) images of updated records. This option allows backward (backout) recoveries only AFTER—The IAM log data set contains after (redo) images of updated records. This option allows forward recoveries only NONE—The IAM journaling feature is not used for this IAM data set
Limit Keys	Specifies a value from 3 to 64 that indicate the number of keys in a set of compressed keys.
Multi-Volume Override	Specify a space quantity to request when IAM believes that the next extent will be placed on the next candidate volume. The default is specified in the IAM Global Options Table and shipped as MULTIVOLUME=PRIMARY.
Pagefix	Specifies that for Linear / Encrypted Data Sets, write buffers will be page fixed when specified on a File Load step CREATE Override. This will result in slightly lower CPU usage, more so when 64-bit buffers are being used.
Prime Extension	Specification of PE=0 will circumvent normal VSAM rules by allowing a file to be loaded with 0 records. Standard VSAM requires at least one record to be inserted into a file before it is considered to be in the loaded state.
Prime Related Overflow	Specifies whether or not IAM will use the Prime Related Overflow (PRO) for this dataset. Valid values are: Y (Yes)—Uses the PRO format for this data set. N (No)—Do not use the PRO format for this data set.
Secondary Multi Factor	Specifies a value from 0 to 25 as a multiplication factor for the secondary space quantity when the data set exceeds five extents on a volume.
Release Space	Indicates whether or not IAM is to release unused and unreserved DASD space whenever the file is loaded.
RLSID	Specify * (RLSID without an operand) to indicate that this data set is processed by using IAMRLS, regardless of Share Options or the IAMRLS Dataset Name Tables. If specified, the four character identifier of the IAMRLS address space will be preferred that this dataset is to be processed by.
RRDSLOAD	(Optional) Specify the following values: SEQUENTIAL—Specifies that the RRDS file is loaded in ascending relative record number sequence RANDOM—Specifies that the RRDS file is loaded in a random relative record number order
Variable Records in Overflow	For Enhanced format files, specify that IAM should use true variable length records in the Extended Overflow area. Variable Overflow provides a more efficient use of DASD space. The default value is from the IAM Global Options table, which is shipped set to YES.
PSEUDO RBA	Specifies that an IAMESDS file can exceed 4 GB with the use of non-standard 4-byte RBAs (Relative Byte Addresses). If the application has dependency on the RBA to be identical to VSAM, then this parameter must not be used.
Extended ESDS	For ESDS files, (Optional) enter one of the following options: Y (Yes)—Specifies to use an 8-byte RBA value so that ESDS can exceed 4 GB of user data. The application programs should be able to handle the 8-byte RBA. This is consistent with the VSAM Extended Addressability support. N (No)—Specifies that a 4-byte RBA is used to limit the size to 4 GB.
Allocation Options
Expiration date	(Optional) Specify a date after which deletion or update of the data set is permitted in the format: YYYY/MM/DD.
Reuseable	Specify whether the cluster is to be reusable with a value of Y (Yes) or N (No).
Share Option	Specify the type of sharing between regions: 1—Multi-user: read only; single user: read/write 2—Multi-user: read; single user: write 3—Multi-user: read/write 4—Multi-user: read/write, requires ENQ and DEQ.
Extended Attributes	(Optional) Enter one of the following values: O—Specify that extended attributes should be optional for this data set. N—Specify that the data set cannot have extended attributes.
Spanned records	Enter Y (Yes) or N (No) to specify whether data records can be longer than the control interval length and can cross (span) control intervals.
LOGREPLICATE	(Optional) Enter one of the following values: LOGREPLICATE - IAM data set is eligible for VSAM replication. When LOGREPLICATE is specified then you must also specify LOGSTREAMID. NOLOGREPLICATE - The data set is not eligible for VSAM replication.
LOG	(Optional) Enter one of the following values: NONE—Data set to be nonrecoverable UNDO—Data set to be backward recoverable ALL—Data set to be both backward and forward recoverable
LOGSTREAMID	Gives the name of the forward recovery log stream.
Encryption
Keylabel	(z/OS 2.3 and up) Identifies the name, up to 64 bytes, of the key label to be used to encrypt the new data set.
FRLOG (Batch Logging)	(Optional) Enter one of the following values: ALL—Enables the changes made to your IAM data set to be both backed out and forward recovered by using the VSAM logging NONE—Data set can be used for VSAM batch logging. However, you should disable the function REDO—Enables forward recovery of the changes made to your IAM data set by using VSAM logging UNDO—Enables the backing out of the changes made to your IAM data set by using VSAM logging
Multiple volumes	Specify whether you want to allocate the data set on multiple volumes. Valid entries are Y (Yes) or N (No).

Allocate IAM

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