Format of IMS catalog activity records

IMS catalog activity records are stored as type-29, subtype-3 records in z/OS® System Management Facility (SMF).

The BPESMF29 macro contains the DSECTs for both the SMF type 29 and the BPE headers.

SMF header

Table 1. SMF header (type 29) – BPESMF29 DSECT
Name Length Type Description
smf29len 2 binary Record length
smf29seg 2 binary Segment descriptor
smf29flg 1 binary System indicator flag:
  • x'80' – Reserved
  • x'40' – Subtype used
  • x'20' – Reserved
  • x'10' – MVS/SP version 4 and above
  • x'08' – MVS/SP version 3
  • x'04' – MVS/SP Version 2
  • x'02' – VS2
  • x'01' – Reserved
smf229rty 1 binary Record type (29 decimal or x'1D')
smf29tme 4 binary Time since midnight in hundredths of a second
smf29dte 4 packed Date (packed decimal) when the record was moved into the SMF buffer
smf29sid 4 EBCDIC System identification
smf29ssi 4 EBCDIC Subsystem identification
smf29sty 2 binary Record subtype
smf29trn 2 binary Number of triplets in this record
* 2   Reserved
smf29bhs 4 binary Offset to BPE header from start of record
smf29bhl 2 binary Length of BPE header
smf29bhn 2 binary Number of BPE header
smf29sts 4 binary Offset to subtype specific section from start of record
smf29stl 2 binary Length of subtype specific section
smf29stn 2 binary Number of subtype specific section

The smf29bhs, smf29bhl, and smf29bhn fields will be zero because the BPE headers are not written for an IMS catalog activity record.

Example subtype 3 log records

Subtype-3 records have a self-defining "triplet" section at offset SMF29STS from the start of the record. These triplets define the offsets, lengths, and number of follow-on sections in the record. For example:

Table 2. Example Self-defining triplets
Name Length Type Description
SMF29STY3_N 2 binary Number of triplets in this section
* 2 binary Reserved
SMF29STY3_CSO 4 binary Offset to common section
SMF29STY3_CSL 2 binary Length of common section
SMF29STY3_CSN 2 binary Number of common sections
SMF29STY3_TSO 4 binary Offset to type-specific section
SMF29STY3_TSL 2 binary Length of type-specific section
SMF29STY3_TSN 2 binary Number of type-specific sections

Sub-type-3 records have a common section at offset SMF29STY3_CSO. This common section contains all the common elements found in all catalog activity records. For example:

Table 3. Example common section
Name Length Type Description
SMF29STY3_PVER 2 binary Version number. Indicates the iteration of the format of the SMF record layout. This value will increase by one with each subsequent change to the layout.
SMF29STY3_FUNC 2 binary Type of activity recorded. See the DFS3SMF macro for valid values.
SMF29STY3_RECNUM 2 binary Remaining continuation records for partial records. If the type-specific portion length exceeds the amount of space in a single SMF record, then multiple SMF records will be written, each with a portion of the total type-specific data. SMF29STY3_RECNUM will be non-zero (and decreasing) until the last record, which will be zero.
SMF29STY3_FLAGS 2 binary Field flag bytes (not currently used).
SMF29STY3_JOBNAME 8 EBCDIC Job name of the process that is initiating the record.
SMF29STY3_USERID 8 EBCDIC ID of the process that is initiating the record.
SMF29STY3_IDLEN 2 binary Length of the process identifier.
SMF29STY3_ID 64 EBCDIC Process identifier. If present, provides more identifying information for the process that is initiating the record.
SMF29STY3_STCKE 16 binary Store clock (STCKE).
SMF29STY3_IMSID 4 EBCDIC IMS id

Subtype-3 records have a component- or type-specific section at offset SMF29STY3_TSO from the beginning of the record. Each provider of subtype-3 records determines the contents and layout of the type-specific section. See the DFS3SMF macro for the layout.