When you take an SMS trace with the VTOCC or VTOCA option, then (if volume selection was not prematurely terminated by an error), the trace facility will also create a trace entry containing an IGDVSUIB (volume selection user information block) in the private area of the SMS address space for each data set being traced. IGDVSUIB will contain key information used in SMS volume selection, which you can use to perform problem diagnosis on volume selection problems.
| Offset Dec(Hex) | Bytes and Bit Pattern | Field Name | Description |
|---|---|---|---|
| 0 (X'00') | 8 | ID | Control block name IGDVSUIB |
| 8 (X'08') | 2 | VERNO | Control block version number |
| 10 (X'0A') | 2 | * | Reserved |
| 12 (X'0C') | 4 | LEN | Length of IGDVSUIB |
| 16 (X'10') | 4 | VOL_CTR | Number of volumes in table |
| 20 (X'14') | 44 | DSN | Data set name |
| 64 (X'40') | 8 | SC | Storage class name |
| 72 (X'48') | 8 | DC | Data class name |
| 80 (X'50') | 4 | SPACEKB_REQUESTED | Requested space for nonVSAM or Cluster/Data component |
| 84 (X'54') | 4 | SPACEKB_REQUESTED | Requested space for Index |
| 88 (X'58') | 1 | DS_TYPE | DS Type - VSAM or NonVSAM |
| 89 (X'59') | 3 | * | Reserved |
| 92 (X'5C') | 4 | DS_FLAGS | Flags |
| DS_FLAG1 | First flag byte | ||
| 1... .... | VSAM_DS | VSAM data set | |
| .1.. .... | GUARANTEED_SPACE | Guaranteed space request | |
| ..1. .... | BEST_FIT_REQUEST | Best fit request | |
| ...1 .... | STRIPING_REQUEST | Striping request | |
| .... 1111 | Reserved | ||
| 96 (X'60') | 16 | * | Reserved |
| VOL_VAR | Start of variable part | ||
| 112 (X'70') | 8 | SG | Storage group name |
| 120 (X'78') | 1 | SG_TYPE | Storage group type: 1 - POOL, 2 - Overflow, 3 - Extend |
| 121 (X'79') | 3 | * | Reserved |
| 124 (X'7C') | 6 | VOLSER | Volume serial number |
| 130 (X'82') | 1 | * | Reserved |
| 131 (X'83') | 1 | VOL_STATE | Volume state: S - Selected, N - Not used, R - Rejected |
| 132 (X'84') | 4 | TOTAL_SPACEMB | Total space in MB |
| 136 (X'88') | 4 | FREE_SPACEMB | Free space in MB |
| 140 (X'8C') | 4 | THRESHOLD_SPACEMB | Below threshold space in MB |
| 144 (X'90') | 4 | VOL_PREFERENCE | Volume selection preference |
| Byte 1 | |||
| 1....... | Meet PCU separation criteria if specified | ||
| .1...... | Meet extent pool separation criteria if specified | ||
| ..1..... | Meet volume separation criteria if specified | ||
| ...1.... | Not space-efficient volume | ||
| ....1... | Meet volume count criteria for non-VSAM data set | ||
| .....1.. | Below 120% of high threshold | ||
| ......1. | Meet primary high threshold | ||
| .......1 | Meet secondary high threshold | ||
| Byte 2 | |||
| 1....... | Enabled SMS status | ||
| .1111... | Multi-tiered storage group ranking if specified | ||
| .....1.. | Non-extend storage group | ||
| ......1. | Non-overflow storage group | ||
| .......1 | Mountable volume | ||
| Byte 3 | |||
| 1....... | Meet Fast Replication or SFI eligibility | ||
| .1...... | Meet Cluster eligibility | ||
| ..1..... | Meet Extent Pool eligibility | ||
| ...1.... | Meet Controller eligibility | ||
| ....1... | Meet EAS eligibility | ||
| .....11. | Meet PREFERRED | STANDARD accessibility criteria | ||
| .......1 | Meet PREFERRED | STANDARD PAV criteria | ||
| Byte 4 | |||
| 1....... | Meet PREFERRED | STANDARD availability criteria | ||
| .1...... | Meet PREFERRED extent format criteria | ||
| ..111111 | not used | ||
| Byte 5 | |||
| 11111111 | MSR band rank | ||
| 148 (X'94') | 4 | FAIL_FLAGS | Failure reason flags |
| Byte 1 | |||
| 1....... | SMS status Disabled | ||
| .1...... | MVS status NOT ONLINE | ||
| ..1..... | No UCB available | ||
| ...1.... | Not meet Continuous availability | ||
| ....1... | Not meet Standard, Pref or no-pref availability | ||
| .....1.. | Not meet accessibility | ||
| ......1. | Not meet data set separation criteria | ||
| .......1 | Rejected for insufficient space for best-fit | ||
| Byte 2 | |||
| 1....... | Rejected by DADSM for duplicate data set name | ||
| .1...... | Rejected by DADSM for no room in VTOC or index | ||
| ..1..... | Rejected by DADSM for I/O or CVAF error | ||
| ...1.... | Rejected by DADSM installation exit | ||
| ....1... | Rejected by DADSM because not initialized | ||
| .....1.. | Rejected by DADSM because EOF mark write failed | ||
| ......1. | Rejected by DADSM for insufficient space | ||
| .......1 | Rejected by other DADSM failure | ||
| Byte 3 | |||
| 1....... | Not meet striping criteria | ||
| .1...... | Not an unmountable volume | ||
| ..1..... | No DPCT available | ||
| ...1.... | Not on include list | ||
| ....1... | On exclude list | ||
| .....1.. | Not correct device type | ||
| ......1. | Could not be allocated | ||
| .......1 | Not eligible for class transition | ||
| Byte 4 | |||
| 1....... | Failed by IGWSSEOV during extend processing | ||
| .1...... | Not meet fast replication criteria | ||
| ..1..... | Not meet PAV criteria | ||
| ...x.... | Not used | ||
| ....1... | Rejected for insufficient total space | ||
| .....1.. | Rejected for insufficient free space | ||
| ......1. | EAV volume rejected due to USEEAV(NO) | ||
| .......1 | Volume rejected because it is an SE volume | ||
| 152 (X'98') | 4 | DADSM_DIAGDATA | DADSM diagnostic code |
| 156 (X'9C') | 16 | * | Reserved |