IAMINFO Report Description
The following tables will describe the various fields that appear on the IAMINFO Report.
IAM400
Indicates the version and level of IAM that processed the data set, and the date of the report.
IAM360
Provides the Step Name, the DD Name of the file being processed, and the Data set Name.
IAM361
Indicates the name of the program that opened the IAM data set, file processing mode (Creation, Input, or Update), and the open and close time stamps.
IAM362
Data Characters
IAM FILE FORMAT | Indicates if the file is an ENHANCED format IAM data set, which may also be indicated as LARGE-FRMT if it is in a Large Sequential format data set, or SMS-EXT for a SMS Extended format. The File Format may also be ENCRYPTED if Pervasive Encryption is enabled for the file. The other possibility is a COMPATIBLE format IAM data set, which is required for use by the older non-VSAM interfaces. |
IAM FILE STATUS | Indicates whether the file is in a LOADED state, or an UNLOADED state. |
LOGICAL RECORD LENGTH | The maximum record length, as specified when the data set was defined. |
CI SIZE | The control interval (CI) size specified when file was defined. If no explicit CI size was provided, then IAM calculates a value based on the maximum record size. |
KEY SIZE | The length of the key specified when file was defined. The maximum key length for an IAM data set is 249 bytes. |
KEY OFFSET | The relative position of the key within the user data record. (RKP) The key must be positioned within the first 4K of the data record. |
AVERAGE RECORD LENGTH | During a load operation IAM calculates an average length for the records that were loaded into the file. For data compressed files, the length is after compression. NOTE: This field only appears for a file CREATION report. |
LARGEST RECORD PROCESSED | During a load operation IAM reports the length of the largest record that was written to the file. NOTE: This field only appears for a file CREATION report. |
TOTAL RECORDS | The total number of records in the IAM file. NOTE: This field does not appear on a file CREATION report. |
TOTAL RECORDS DELETED | The total number of records deleted from the IAM file since creation. NOTE: This field does not appear on a file CREATION report. |
TOTAL RECORDS UPDATED | The total number of records updated in the IAM file since creation. NOTE: This field does not appear on a file CREATION report. |
TOTAL RECORDS INSERTED | The total number of records inserted into the IAM file since creation. NOTE: This field does not appear on a file CREATION report. |
IAM363
File Characteristics
BLOCKING FACTOR | A value of 1 to 15 is the number of blocks per track (as blocking factor). A larger value indicates the requested block size from the IAM CREATE B= override. |
BLOCKSIZE | Physical block size of the IAM file. This is the actual block size developed and used by IAM. |
TRACKS IN USE | Number of tracks currently being used by IAM for the file. Does not include unused (available) Extended blocks. |
VARIABLE LENGTH OVERFLOW | A YES value indicates that IAM will fit as many records as possible into an extended overflow block. A NO value indicates that IAM will only put in the number of maximum size records that will fit within an overflow block. A value of PRO indicates that the Prime Related Overflow structure is being used for this data set. |
NUMBER OF EXTENTS | The total number of DASD extents allocated to theIAM file. |
NUMBER OF VOLUMES | The number of volumes allocated to the IAM file. This may include volumes that do not have any actual space allocated to the data set, but will not include DFSMS candidate volumes. |
DATA SET TYPE | Describes the type of data set IAM is simulating. Possible values include: KSDS, for key sequenced data set, ESDS for entry sequence, (i.e. sequential), ESDS/P for ESDS files defined with PSEUDORBA specified, AIX for an alternate index, or RRDS for an RRDS data set. |
SHARE OPTIONS | Indicates the defined cross region share option for this file. Possible values are: 1, 2, 3, or 4. The use of IAM files with Share Option 3 or 4 is not recommended, as possible data loss can occur. |
NUMBER OF IAM DATA BLOCKS | The number of blocks in the file up to where the prime index begins. This field may be needed to run IAMRECVR for recovery if the first block in the file has been damaged. |
HIGH ALLOCATED RBN | This the highest allocated block number currently in the IAM file. This field may be needed to run IAMRECVR for recovery if the control information about the file has been damaged. |
INTEGRATED OVERFLOW (CI%) | The amount of space, as a percentage, left free in each prime data as the file is being loaded. The space can subsequently be used for file expansion. This value is specified as and is similar in concept to CI Freespace. |
DASD RESERVE (CA%) | Indicates the CA Freespace value that was specified when the file was defined. This is used by IAM to reserve some space for future expansion during automatic space release, which occurs during the first file load. |
FILE DEFINED DATE / TIME | The date and time that the file was defined. |
FILE LOADED DATE / TIME | The date and time of the completion of the last file load or reorganization for this file. |
FILE UPDATE DATE / TIME | The date and time the file was last closed by a program that updated the file. |
IAM372
Extended Area Characteristics
EXT. OVERFLOW RECORDS | Number of records currently contained in extended overflow blocks. |
EXT. OVERFLOW BLOCKS | Number of formatted extended overflow blocks. |
EXTENDED BLOCKS ALLOCATED | Number of extended overflow blocks that will fit within the current amount of DASD space allocated to the file. |
EXTENDED PE BLOCKS | Number of extended blocks assigned as Prime Extension (PE) blocks. |
EXTENDED BLOCKS USED | Total number of extended overflow blocks in use. This includes Overflow, PE, and Extended Index blocks. |
EXTENDED BLOCKS AVAILABLE | The number of extended blocks that are available for use within the currently allocated DASD space. |
IAM365
Execution Statistics
TOTAL STORAGE REQUIRED | Total virtual storage from the job's address space acquired by IAM during this execution for this data set used for control blocks, index areas, and buffers. This includes both above the 16MB line and below the 16MB line, but does not include any 64-bit storage used. |
PRIME INDEX | Indicates the amount of virtual storage required for the index to the prime data area of this file. Also, if the index is in a compressed format, the word COMPRESSED appears. |
STORAGE ABOVE THE LINE | Total amount of virtual storage acquired above the 16MB line. |
COMPRESSED DATA STRUCTURE | Indicates whether data compression was used for this file. |
64-BIT BUFFER STORAGE (K) | The amount, in kilobytes, of 64-bit virtual storage used for buffers. . |
TURBO BUFFERING | Indicates whether or not the IAM Real Time Tuning is enabled for Turbo mode, which provides for improved responsiveness when a data set has heavy physical I/O occurring. |
INDEX SPACE USED (K) or | The amount of virtual storage, in KB, used by this data set for the index when the index is in either a z/OS Data Space or in 64-bit addressable storage. |
TOTAL JOB | The total amount of virtual storage, in KB, used so far by IAM in this job step in either a z/OS Data Space or in 64-bit addressable that was acquired for the IAM Index Structure. |
REQUESTS PROCESSED | Number of requests made against the file, since last OPEN, by the application (a breakdown by command type follows in the command execution summary). |
REQUESTS FAILED | Number of requests made to IAM which did not complete normally (i.e. EOF on sequential read, no record found on random read) |
DISK BLOCKS READ | Number of physical I/O's used to read blocks from the file. |
DISK BLOCKS WRITTEN | Number of physical I/O's used to write blocks to the file, except during a load of a SMS Extended format data set, in which case this is will be the number of blocks written to disk. |
DYNAMIC BUFFER RETRIEVALS | Number of times that IAM was able to retrieve a block from the buffer pool without the need for a physical I/O. |
MAXIMUM BUFFERS USED | The maximum number of data buffers acquired by IAM's Real Time Tuning during this execution. This may be accompanied by an IAM367 or IAM368 informational message indicating that if IAM was allowed to acquire more buffers the number of I/O's required to service the requests against the file could have been reduced. All buffers are acquired above the 16MB line. |
DYNAMIC TABLE RETRIEVALS | Number of random read requests satisfied by IAM's Dynamic Tabling or by IAM’s Dynamic Data Space. Those features enable the caching of records in virtual storage. IAM's Dynamic Table (DYNCORE) is maintained in virtual storage above the 16MB line. The Dynamic Data Space (DYNDS) is a separate Data Space containing the records. |
DYNAMIC TABLE RECORDS | The total number of data records IAM placed into the Dynamic Table or the Dynamic Data Space. |
DATA SPACE USED | The amount of area actually used in the data space during file load. |
DATA SPACE SIZE | For a file load, the size of the data space created during file load. |
Z/HPF I/O REQUESTS | The number of physical I/Os that used z/HPF architecture I/O |
ECKD I/O REQUESTS | The number of physical I/Os that used the standard ECKD or CKD type channel program |
IAM366
Command Execution Summary
GET RANDOM | Number of random READ requests with an exact key specified. |
PUT UPDATE | Number of UPDATE requests. |
GET SEQUENTIAL | Number of sequential GET requests. |
PUT ADD | Number of INSERT requests. |
GET PREVIOUS | Number of GET PREVIOUS requests. |
POINT (START BROWSE) | Number of POINT requests. |
GET CI (SEQUENTIAL) | Number of sequential control interval GETS. (ESDS only) |
PUT CI (UPDATE) | Number of CONTROL INTERVAL UPDATES (ESDS only) |
GET CI (RANDOM) | Number of CONTROL INTERVAL GETS (ESDS only) |
PUT CI (ADD) | Number of CONTROL INTERVAL ADDS (ESDS only) |
GET KGE/GENERIC | Number of random or skip sequential reads, indicating search for key greater or equal, and /or partial key search. (KSDS only) |
POINT KGE/GENERIC | Number of POINT, or START BROWSE, requests indicating a search for key greater or equal, or partial key search. (KSDS only) |
GET (SKIP SEQUENTIAL) | Number of GET’s issued in Skip Sequential mode, with an exact key specified. (KSDS only) |
ERASE | Number of requests to delete records. (KSDS only) |
ENDREQ | Number of LSR ENDREQ requests |
WRTBFR | Number of LSR WRTBFR requests |
IAM STATISTICS | Number of IAM statistic requests |
IAM FLUSH BUFFER | Number of IAM flush buffer requests |
CLOSE | Number of CLOSE requests |
OPEN | Number of OPEN requests |
CLOSE TYPE=T | Number of TEMPORARY CLOSE requests |
VERIFY | Number of VERIFYs |
INVALID REQUESTS | Number of requests with RPL error's |
RECORD LENGTH CHANGES | Number of records with length changes |
SEQ CHAINED BLOCKS READ | Number of chained buffers during READ I/O. |
SEQ CHAIN WRITTEN | Number of chained buffers during WRITE I/O. |