DASD Capacity Planning Record Field

This is the section for DASD capacity planning information. If DASD capacity planning records are requested, one record is created for each level 0 and level 1 volume for each day there was activity. For example, if five volumes had DFSMShsm activity for seven days, there would be 35 DASD capacity planning records. The number of days that volume statistics are kept to create these records can be controlled by the MIGRATIONCLEANUPDAYS parameter of the DFSMShsm SETSYS command. The record type for this record is C.
Name
Description
UCVOLSR
Identifies the serial number of the volume.
UCCOLDT
Identifies the date on which statistics were collected for this volume. Only the days where there was activity on this volume are recorded. Records are not created for the current day, as the statistics are incomplete and do not represent a full 24-hour period.
UCLEVEL
Identifies the volume level. Only level 0 and migration level 1 volumes are recorded.
UCTOTAL
Indicates the total capacity of this volume in kilobytes.
UCTGOCC
Indicates the target occupancy, or low threshold, assigned to this volume. This is the percentage of the volume that you want to contain data after migration processing. The percentage can range from 0 to 100. This field does not apply to migration level 1 volumes.
UCTROCC
Indicates the high threshold assigned to this volume. When this percentage of the volume is filled with data, it indicates that you should run interval migration except for volumes in storage groups with AM=I.

For storage groups with AM=I, the percentage of the volume is the midpoint between UCTGOCC and UCTROCC that indicates when you should run interval migration.

UCBFOCC
Indicates the occupancy of the volume before it has been processed by either automatic primary or automatic secondary space management. For level 0 (user) volumes, this processing is done during automatic primary space management. For migration level 1 volumes, this processing is done during automatic secondary space management. This is a percentage value ranging from 0 to 100.
UCAFOCC
Indicates the occupancy of the volume after it has been processed by either automatic primary or automatic secondary space management. For level 0 (user) volumes, this processing is done during automatic primary space management. For migration level 1 volumes, this processing is done during automatic secondary space management. This is a percentage value ranging from 0 to 100.
UCNOMIG
Indicates the excess eligible data occupancy for level 0 and level 1 volumes.

For level 0 volumes: This is the percentage of the level 0 volume that contains data eligible for migration (based on type and date-last-referenced) that did not migrate because the desired volume occupancy was met without it being migrated. This percentage, ranging from 0 to 100, can be considered the safety margin for automatic primary space management.

For level 1 volumes: This is the percentage of the level 1 volume that contains data eligible for migration that did not migrate:

The percentage value is valid only if one of the following conditions is met:
  • The automatic secondary space management window is too short and MGCFDCOL field is patched to X'FF' to allow DFSMShsm to collect the DCOLLECT data. This percentage value will indicate the percentage of the migrated data sets that are eligible to be migrated but are not migrated because the secondary space management window is too short.
  • None of the level 1 volumes trigger the level 1 to level 2 migration because none of their thresholds is met or exceeded. No data movement is initiated from any level 1 volume. This percentage value will indicate the percentage of the migrated data sets that are eligible to be migrated but are not migrated because of the thresholds settings.
  • The automatic secondary space management, including migration cleanup and level 1 to level 2 migration, runs to completion. In this case, all data sets eligible for migration are migrated and hence the percentage of the migrated data sets that are eligible to be migrated, but are not migrated, will be zero.
The percentage value is not valid if one of the following conditions occurs:
  • Automatic secondary space management does not run for the day because it is not scheduled to run, N-day in cycle. In this case, the percentage of the migrated data sets that are eligible to be migrated, but are not migrated, will be zero.
  • Automatic secondary space management runs but does not complete because:
    • DFSMShsm is shut down
    • DFSMShsm is in emergency mode
    • automatic migration is held
    • a target migration volume is not available
    • the maximum number of unsatisfactory or unexpected CDS records is encountered
    • Secondary space management ending time is reached and DFSMShsm is not asked to collect the data by patching the MGCFDCOL field to X'FF'. In this case, the percentage of the migrated data sets that are eligible to be migrated, but are not migrated, will have partial results depending on where the SSM stopped.
UCNINTV
Contains the number of times interval migration has processed this volume on this day. This field does not apply to migration level 1 volumes.
UCINTVM
Contains the number of times interval migration has run and successfully reached the desired target occupancy. This field does not apply to migration level 1 volumes.
Parent topic: DCOLLECT Output Record Field Descriptions