Storage Groups Used in the Sample ACS Routines

The following list describes the storage groups used in the examples. Table 2 summarizes the attributes assigned to tape storage groups, and Table 3 summarizes the attributes assigned to sample tape libraries.

PRIME80, PRIME90

The primary storage groups are assigned to most system-managed data. This data includes interactive, batch, VSAM, striped, and multivolume data sets and some temporary data. These storage groups are also assigned to non-production database data.

Only data sets that are 285 MB or smaller are assigned to these storage groups.

PRIME80 contains 3380 DASD volumes of all models. PRIME90 contains 3390 DASD volumes of all models. Both storage groups allow automatic migration, backup, and dump processing.

LARGE80, LARGE90

The large storage groups are assigned to data sets larger than 285MB. This includes database image copies, archive logs, some temporary data sets, and large interactive, batch, VSAM, striped, and multivolume data sets.

LARGE80 contains 3380 DASD volumes of all models. LARGE90 contains 3390 DASD volumes of all models. Both storage groups allow automatic migration, backup, and dump processing.

The high and low migration thresholds are set at 75% and 60%, respectively, so that sufficient space is available for new and extended data sets.

TMMBUF80, TMMBUF90

The tape DASD buffer storage groups are assigned to new tape data sets that are to be allocated on DASD volumes before DFSMShsm moves them to tape. The low threshold is set to 0% so that all data sets can be moved to tape. The AUTO MIGRATE attribute is set to I so that DFSMShsm can migrate data hourly as needed.

TMMBFS80, TMMBFS90

The overflow tape DASD buffer storage groups (also known as "spill" storage groups) are assigned to new tape data sets that are to be allocated on DASD volumes before DFSMShsm moves them to tape. The overflow storage groups are only used when TMMBUF80 and TMMBUF90 are full. The low threshold is set to 0% so that all data sets can be moved to tape. The AUTO MIGRATE attribute is set to I so that DFSMShsm can migrate data hourly as needed.

CICS®

The CICS database storage group is assigned to CICS production database data. It contains either 3380 or 3390 DASD volumes, but not both.

DB2®

The DB2 database storage group is assigned to DB2 production database data. It contains either 3380 or 3390 DASD volumes, but not both.

IMS™

The IMS database storage group is assigned to IMS production database data. It contains either 3380 or 3390 DASD volumes, but not both.

VIO

The VIO storage group is assigned to temporary non-VSAM data sets smaller than 20 MB, except DFSORT temporary data sets, which are assigned to the primary or large storage groups.

ATLSG

This is a tape storage group for the 3494 or 3495 Automated Tape Library Dataserver. The tape storage group associates the automated tape library with the ATLSG storage group.

MTLSG

This is a tape storage group for the 3495-M10 Manual Tape Library Dataserver. The tape storage group associates the manual tape library with the MTLSG storage group.

MTLREMOT

This is a tape storage group for the 3495-M10 Manual Tape Library Dataserver. The tape storage group associates the “MTLREMOT” tape library with the MTLREMOT storage group. This storage group defines a remotely attached manual tape library connected by ESCON® channels.

Table 1 summarizes the attributes assigned to each storage group for the sample SMS ACS routines.

Table 1. Sample DASD Storage Groups
Attributes	Primary and Large Storage Groups
NAME	PRIME80	PRIME90	LARGE80	LARGE90
TYPE	POOL	POOL	POOL	POOL
AUTO MIGRATE	YES	YES	YES	YES
AUTO BACKUP	YES	YES	YES	YES
AUTO DUMP	YES	YES	YES	YES
DUMP CLASS	ONSITE, OFFSITE	ONSITE, OFFSITE	ONSITE, OFFSITE	ONSITE, OFFSITE
HIGH THRESHOLD	95	95	75	75
LOW THRESHOLD	80	80	60	60
GUARANTEED BACKUP FREQUENCY	15	15	15	15
SMS VOLUME OR STORAGE GROUP STATUS	ENABLE	ENABLE	ENABLE	ENABLE
Attributes	Tape Mount Management Storage Groups
NAME	TMMBUF80	TMMBUF90	TMMBFS80	TMMBFS90
TYPE	POOL	POOL	POOL	POOL
AUTO MIGRATE	INTERVAL	INTERVAL	INTERVAL	INTERVAL
AUTO BACKUP	YES	YES	YES	YES
AUTO DUMP	YES	YES	YES	YES
DUMP CLASS	ONSITE, OFFSITE	ONSITE, OFFSITE	ONSITE, OFFSITE	ONSITE, OFFSITE
HIGH THRESHOLD	95	95	75	75
LOW THRESHOLD	0	0	0	0
GUARANTEED BACKUP FREQUENCY	NOLIMIT	NOLIMIT	NOLIMIT	NOLIMIT
SMS VOLUME OR STORAGE GROUP STATUS	ENABLE	ENABLE	ENABLE	ENABLE
Attributes	Database and VIO Storage Groups
NAME	CICS	DB2	IMS	VIO
TYPE	POOL	POOL	POOL	VIO
VIOMAXSIZE	—	—	—	20MB
VIO UNIT	—	—	—	3380
AUTO MIGRATE	YES	YES	YES	—
AUTO BACKUP	YES	YES	YES	—
AUTO DUMP	YES	YES	YES	—
DUMP CLASS	ONSITE, OFFSITE	ONSITE, OFFSITE	ONSITE, OFFSITE	—
HIGH THRESHOLD	75	75	75	—
LOW THRESHOLD	60	60	60	—
GUARANTEED BACKUP FREQUENCY	NOLIMIT	NOLIMIT	NOLIMIT	—
SMS VOLUME OR STORAGE GROUP STATUS	ENABLE	ENABLE	ENABLE	ENABLE

Table 2. Sample Tape Storage Groups
Attributes	Tape Storage Groups
NAME	ATLSG	MTLSG	MTLREMOT	ATLHSMSG	MTLHSMSG
TYPE	TAPE	TAPE	TAPE	TAPE	TAPE
LIBRARY	ATL	MTL	MTLREMOT	ATL	MTL
SMS STORAGE GROUP STATUS	ENABLE	ENABLE	ENABLE	ENABLE	ENABLE

Table 3. Sample Tape Libraries
Attributes	Tape Libraries
NAME	ATL	MTL	MTLREMOT
LIBRARY ID	00AC1	10AC0	AAAC0
CONSOLE NAME	TLIC1CON	ALIB1CON	TLIC1CON
ENTRY DEFAULT DATA CLASS	—	—	—
ENTRY DEFAULT USE ATTRIBUTE	SCRATCH	SCRATCH	SCRATCH
EJECT DEFAULT	KEEP	KEEP	KEEP
MEDIA1 SCRATCH THRESHOLD	150	150	150
MEDIA1 SCRATCH NUMBER	0	0	0
MEDIA2 SCRATCH THRESHOLD	150	150	150
MEDIA2 SCRATCH NUMBER	0	0	0

SAMPLIB contains the sample storage group ACS routine. This routine handles DASD data and tape allocations that are redirected to DASD using tape mount management techniques. It does not assign tape storage groups.

Filter lists are used to identify production databases for CICS, DB2, and IMS, and the storage classes assigned to them.

The routine first implements tape mount management. Tape allocations of temporary data sets are assigned to the large storage groups, LARGE90 and LARGE80, thus preventing unnecessary tape mounts. Other tape allocations are identified according to management class, and redirected to the tape mount management buffers (TMMBUF90, TMMBUF80, TMMBFS90, and TMMBFS80). DFSMShsm moves the data onto tape, reducing tape mounts and making more efficient use of tape resources.

The routine then handles temporary DASD data set allocations. Data sets smaller than 285MB are eligible for VIO or, if larger than the maximum size allowed by the VIO storage group, are allocated in the primary storage groups PRIME90 or PRIME80. The routine checks the storage class assigned, so that only data sets with the STANDARD storage class are eligible for VIO. This ensures that temporary VSAM and DFSORT work data sets are not assigned to the VIO storage group, because the storage class routine assigns the NONVIO storage class to those data sets. Temporary VSAM and DFSORT work data sets are assigned to the primary storage groups by the OTHERWISE statement at the end of the routine.

Next, the routine places CICS, DB2, and IMS production databases in the corresponding storage group.

Most data allocations are handled by the last two steps. Data sets 285MB or larger, including temporary data sets, are placed in the large storage groups. All other data sets are placed in the primary storage groups.

SAMPLIB also contains the sample storage group ACS routines for the activating, temporary, and permanent milestones.