The TSOS privilege implies the general authorization for physical allocation on all user IDs. Systems support can assign individual user IDs the right to physical allocation of their files (see also "Physical allocation" (Requesting storage space)). Physical allocation is performed via the operands VOLUME-SET, VOLUME and SPACE=*ABSOLUTE(..) of the commands CREATE-FILE and MODIFY-FILE-ATTRIBUTES. The VOLUME-SET operand is relevant for SM pubsets only.
The following level of detail may be specified:
Physical allocation at block level The caller specifies both the volume and the blocks within that volume on which storage space is to be reserved.
Physical allocation at volume level The caller specifies the volumes of the pubset on which the file is to be stored. Where exactly on the volumes storage space is reserved is irrelevant for the caller.
Physical allocation at volume set level The caller specifies the volume set on which the file is to be stored. Where exactly on the volume set storage space is reserved is irrelevant for the caller.
Information functions for users with the right to physical allocation
Functions providing information which permit a view of the physical configuration are available to users with the right to physical allocation.
The SHOW-PUBSET-DEFINITION-FILE command provides detailed information on the pubset configuration and the pubset characteristics of SM pubsets.
For the individual volumes it displays the utilization type (STANDARD, HSMS-CONTROLLED, WORK), allocation constraints (NEW-FILE-ALLOCATION) and performance attributes. The performance and availability characteristics rely on the definitions made by systems support, a more detailed description of the underlying physical features (cache type, DRV) is not given.
The SHOW-PUBSET-RESTRICTION command shows the volume sets of the SM pubset, the volumes which belong to it and – as for SF pubsets – the device type and allocation constraints for the individual volumes.
Example
/SHOW-PUBSET-DEFINITION-FILE PUBSET=SMS1,VOLUME-SET=VS01————————————————————— (1) ----------------------------------------------------------------------------- COMMAND: SHOW-PUBSET-DEFINITION-FILE - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - PUBSET SMS1: TYPE = SYSTEM-MANAGED, VOLUMESETS = 3, DEFAULT FILE FORMAT = NK4 ---- VOLUME-SET INFORMATION --------- + ------------------------------------- VOLUME-SET VS01: NORMAL-USE, NK4-FORMAT ---- GLOBAL ATTRIBUTES --------- + ------------------------------------- AVAILABILITY | STANDARD USAGE | STANDARD FORMAT | NK4-FORMAT MAXIMAL I/O LENGTH | 48 HP ALLOCATION UNIT SIZE | 4 HP DRV-VOLSET | NO NEW FILE ALLOCATION | NOT RESTRICTED VOLUME SET ACCESS | NOT RESTRICTED ---- PERFORMANCE ATTRIBUTES --------- + ------------------------------------ PERFORMANCE | STANDARD WRITE-CONSISTENCY | BY-CLOSE -----------------------------------------------------------------------------
(1) | The physical volume set/volume configuration of SM pubset SMS1 is displayed. |
/SHOW-PUBSET-RESTRICTION PUBSET=SMS1———————————————————————————————————————— (2) ----------------------------------------------------------------------------- COMMAND: SHOW-PUBSET-RESTRICTION - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - PUBSET SMS1: TYPE = SYSTEM-MANAGED, VOLUMESETS = 3, DEFAULT FILE FORMAT = NK4 ---- PHYSICAL CONFIGURATION --------- + ------------------------------------- ---- VOLUME-SET INFORMATION --------- + ------------------------------------- VOLUME-SET VS00: VOLUMES = 2 VOLUME CONFIGURATION: VOLUME DEVICE ALLOCATION VOLUME DEVICE ALLOCATION VS00.0 D3435 NOT RESTR VS00.1 D3435 NOT RESTR VOLUME-SET VS01: VOLUMES = 1 VOLUME CONFIGURATION: VOLUME DEVICE ALLOCATION VOLUME DEVICE ALLOCATION VS01.0 D3435 NOT RESTR VOLUME-SET VS02: VOLUMES = 1 VOLUME CONFIGURATION: VOLUME DEVICE ALLOCATION VOLUME DEVICE ALLOCATION VS02.0 D3435 NOT RESTR -----------------------------------------------------------------------------
(2) | The global volume set attributes (availability, utilization type, allocation constraints, etc.) and the performance attributes (performance profile and write consistency) of the volume set VS01 in SM pubset SMS1 are displayed. |
For SM pubset entries, the SHOW-MASTER-CATALOG-ENTRY command supplies information about global pubset states (e.g. accessible, inaccessible, local, remote, see the “HIPLEX MSCF” manual [11 (Related publications)]). For volume set entries, the command supplies the associated pubset. The structure of SM pubsets must also be account where the STAMCE macro interface is used:
Global pubset states (accessible, inaccessible, etc.) are indicated via the MRSCAT entry for the pubset (as for SF pubsets).
With SM pubsets, configuration data concerning cache assignments, structure, format, etc. is volume-set-specific and is therefore supplied in the MRSCAT entries for the volume sets. These entries also contain information about the pubset to which the volume set belongs.
Detailed information down to the level of individual blocks is also supplied for SM pubsets by the utility routine SPCCNTRL (DISPLAY function), see the “Utility Routines” manual [13 (Related publications)].
Taking file migration inhibits into account
The file attributes S0-MIGRATION and MIGRATE determine whether a file is allocated a fixed storage location or not. The user can explicitly assign these attributes to a file e.g. via the commands CREATE-FILE and MODIFY-FILE-ATTRIBUTES. They serve as an interface between the user and systems support or the system.
They permit the special requirements of user-controlled files to be recognized and taken into account with little effort when the activities “pubset reorganization” and “migration” (using software product HSMS) are performed which are normally organized by systems support. This is done, for instance, by HSMS excluding files with the attribute MIGRATE-FORBIDDEN from migration and recalling files with the attribute S0-MIGRATION-FORBIDDEN residing on a background level to their original volume set.
Files on Net-Storage are never migrated to a background level.
Physically allocated files and file migration inhibits
A close relationship exists between physical allocation and determining the storage location of a file; it must therefore be taken into account when files are relocated (using software product HSMS) both within the S0 level as between S0 and the background levels. Physical allocation is usually coupled with the request to fix a specific storage location for a file. If initial storage space allocation (i.e. not the extension of an existing file) is requested via physical allocation without explicitly specifying the location-fixing attributes,
S0-MIGRATION and MIGRATE are implicitly preset. The presettings are dependent on the level of detail used for defining the file location:
If the file location was specified at volume set level (VOLUME-SET operand), the implicit presettings are S0-MIGRATION=*FORBIDDEN and MIGRATE=*ALLOWED. The system assumes that the file is to reside on the specified volume set throughout the entire processing at S0 level. Relocation within the volume set is permissible. The file may be migrated to a background level during migration or pubset reorganization; its recall to the original volume set is guaranteed.
In the event of physical allocation at volume or block level, the implicit presettings are S0-MIGRATION=*FORBIDDEN and MIGRATE=*FORBIDDEN. Migration to a background level is not permissible in this case; the location of the file as specified at file creation is retained.
As mentioned earlier, file migration inhibits may be modified explicitly. Since this has a similarly strong effect on a pubset's space utilization as physical allocation, the right to physical allocation is required to explicitly set S0-MIGRATION=*FORBIDDEN and MIGRATE=*FORBIDDEN.
Relation between physical allocation and file attributes
The performance, availability, format and work file attributes serve to specify the requirements for a file. The system takes these requirements into account when selecting a suitable volume set. With physical allocation, the file attributes are irrelevant for determining the file location, since the volume set is in this case specified by the user. However, the file attributes have other functions which are relevant for physically allocated files as well:
If a volume set is equipped with a cache, the performance-related file attributes control cache utilization.
Usually, the format of files residing on a volume set (K, NK2, NK4) is not unequivocally defined by that volume set. Additional and more detailed specifications are required.
The file attributes serve to determine the user contingents “debited” by the storage space occupied by a file.
Files are consequently assigned valid values for the file attributes PERFORMANCE, IO-USAGE, DISK-WRITE, AVAILABILITY, PREFORMAT and USAGE even if they are created by means of physical allocation. However, physical allocation and non-physical allocation differ in certain aspects such as default values and consideration of explicit user specifications:
Attributes already assigned as a result of the volume set selected are taken into account and entered.
If any user-specified attributes are incompatible with the characteristics of the volume set selected, the user request is rejected.
Storage classes and physical allocation cannot be used in combination.
Relation between S0 migration inhibit and file attributes
As with physical allocation, it must be ensured that contingent monitoring cannot be ignored when modifying the attributes of a file for which an S0 migration inhibit is set or when setting the migration inhibit for a file. Therefore, current or user-specified attributes may be modified automatically in these cases as well. If, for instance, a user creates a file with the attribute AVAILABILITY=*HIGH, subsequently changing it to AVAILABILITY=*STD, S0-MIGRATION=*FORBIDDEN by means of a MODIFY-FILE-ATTRIBUTES command, the file is implicitly reassigned the original attribute AVAILABILITY=*HIGH.