Storage Class Construct Field
This is the section for Storage Class Construct information. These
records are collected when SMSDATA is selected, and Storage Class
constructs are defined to the control data set selected. The record
type for this record is 'SC'.
- Name
- Description
- DSCNMFLD
- The Storage Class Construct name.
- DSCNMLEN
- The length of this construct name.
- DSCNAME
- The name of this construct.
- DSCUSER
- The USERID of the last person to make a change to this construct.
- DSCDATE
- The date that this construct was last changed. The format is "YYYY/MM/DD" in EBCDIC.
- DSCTIME
- The time that this construct was last changed. The format is "HH:MM" in EBCDIC.
- DSCDESC
- The description of this construct.
- DSCFLAGS
- Storage Class Parameters Specification Flags. The following are
indicated if the specified bit is '1'.
- DSCDFGSP
- This bit indicates that guaranteed space is to be allocated. Multi-volume data sets can be pre-allocated with the same or different amounts of space on more than one volume.
- DSCDFAVL
- Availability options have been specified, see DSCAVAIL.
- DSCFDIRR
- Direct access response time objective has been specified, see DSCDIRR.
- DSCFDIRB
- Direct access bias has been specified, see DSCDIRB.
- DSCFSEQR
- Sequential access response time objective has been specified, see DSCSEQR.
- DSCFSEQB
- Sequential access bias has been specified, see DSCSEQR.
- DSCSYNCD
- This bit indicates that the system should return from a BSAM CHECK issued for a WRITE against a PDSE member after (synchronized) the data has actually been written to a storage device.
- DSCFIAD
- Initial access response time has been specified, see DSCIACDL.
- DSCFLAG2
- Storage Class Parameters Specification Flags Byte 2. The following
are indicated if the specified bit is '1'.
- DSCDFACC
- Accessibility has been specified. See DSCACCES.
- DSCDFSDR
- Striping Sustained Data Rate has been specified. See DSCSTSDR.
- DSCFDCFW
- Direct CF weight has been specified; see DSCDIRCW.
- DSCFSCFW
- Sequential CF weight has been specified; see DSCSEQSW.
- DSCFPAV
- PAV options have been specified; see DSCPAV.
- DSCDSSEP
- Data set separation has been specified
- DSCTIER
- Multi-tier storage class or not
- DSCACCVF
- ACC version parameter specified; see DSCACCV.
- DSCFLAG3
- Storage Class Parameters Specification Flags Byte 3. The following
are indicated if the specified bit is '1'
- DSCACCBF
- ACC Backup parameter specified; see DSCACCB.
- DSCAVAIL
- This field shows the availability options specified for the Storage
Class and is mapped by DSCAVLDC, DSCAVLST, DSCAVLCN, and DSCAVLPR.
- 0
- Do not care about availability.
- 1
- Use standard availability.
- 2
- Use continuous availability.
- 3
- Continuous availability preferred.
- DSCDIRB
- This field shows the direct access bias for data sets in this
storage class. The direct access bias tells whether the majority
of I/O scheduled for the data sets in this storage class is for READ,
WRITE, or unknown. This field is mapped by DSCBIADC, DSCBIARD, and
DSCBIAWR.
- 0
- Direct access bias is unknown.
- 1
- Direct access has read bias.
- 2
- Direct access has write bias.
- DSCSEQB
- This field shows the sequential access bias for data sets in this
Storage Class. The sequential access bias shows whether the majority
of I/O scheduled for the data sets in this Storage Class is for READ,
WRITE or unknown. This field is also mapped by DSCBIADC, DSCBIARD,
and DSCBIAWR.
- 0
- Sequential access bias is unknown.
- 1
- Sequential access has read bias.
- 2
- Sequential access has write bias.
- DSCACCES
- This field specifies whether the data sets in this storage class
should be allocated to volumes supported by concurrent copy. When
used with the ABACKUP/BACKUP COPY TECHNIQUE attributes of the management
class, this field determines if the data sets should retain continuous
write access during backup.
- 0
- Continuous Preferred - The data set should be allocated to volumes supported by concurrent copy. If this cannot be done, a data set can be allocated to volumes that do not support concurrent copy.
- 1
- Continuous - The data set must be allocated to volumes supported by concurrent copy. The allocation is unsuccessful for data sets that cannot be allocated to such volumes.
- 2
- Standard - The data set should be allocated to volumes that do not support concurrent copy. If this cannot be done, a data set can be allocated to volumes that support concurrent copy.
- 3
- Nopref - The data set is allocated to volumes whether or not the volumes are concurrent copy capable.
- DSCIACDL
- This field indicates the time required (in seconds) to locate, mount, and prepare media for data transfer.
- DSCDIRR
- This field shows the direct access response time required for data sets in this storage class. The value is the number of milliseconds required to read or write a 4-kilobyte block of data.
- DSCSEQR
- This field shows the sequential access response time required for data sets in this storage class. The value is the number of milliseconds required to read or write a 4-kilobyte block of data.
- DSCSTSDR
- This field shows the sustained data transfer rate for data sets in this storage class. The system uses this value to determine the number of stripes it will try to allocate for the data set.
- DSCCCHST
- Cache set name, comprised of two parts - DSCCSLEN (length of following name), and DSCSNAM
- DSCDIRCW
- Direct CF weight
- DSCSEQCW
- Sequential CF weight
- DSCPAV
- PAV value specified for use in the volume selection process
- 0 - The PAV status of the volume is not considered in the volume selection algorithm
- 1 - Volumes with no PAV capability are preferred over volumes with PAV capability (Standard)
- 2 - Volumes with PAV capability are preferred over volumes without PAV capability (Preferred)
- 3 - Only volumes with PAV capability will be eligible for selection (Required)
- DSCACCV
- Versioning device information
- DSCACCB
- Backup device information