z/OS V1R6.0 DFSMS Access Method Services for Catalogs

ALLOCATE||||||||||||||||||||||||||||||||||||||||||||||vvvAVBLOCK(value): The AVBLOCK parameter’s value is multiplied by theSPACE parameter’s quantity.CYLINDERS: The SPACE parameter’s quantity is given in cylinders.TRACKS: The SPACE parameter’s quantity is given in tracks.Use SPACE for NEW and MOD data sets.quantityAllocates the initial number of units of space for a data set. For apartitioned data set, a directory quantity is not necessary.incrementThis is the number of units of space to be added to the data set each timethe previously allocated space has been filled. You must provide theprimary quantity along with the increment value.BLOCK(value)Shows the average length (in bytes) of the records written to the data set.The maximum block value used to determine space to be allocated is65,535. The block value is the unit of space that is used by the SPACEparameter. A track or a cylinder on one device can represent a differentamount of storage (number of bytes) from a track or a cylinder on anotherdevice. Determine the unit of space value from the:vvvDefault value of (10 50) AVBLOCK(1000) if no space parameters (SPACE,AVBLOCK, BLOCK, CYLINDERS, or TRACKS) are given.The BLOCK parameter.The model data set, if the LIKE parameter is used and BLOCK,AVBLOCK, CYLINDERS, or TRACKS is not given.v The BLKSIZE parameter if BLOCK is not used.AVBLOCK(value)This shows only the average length (in bytes) of the records that arewritten to the data set.CYLINDERSRequests allocation in cylinders as the unit of space.TRACKSRequests allocation in tracks as the unit of space.Exception: If you specify tracks for a VSAM data set, the space allocatedwill be contiguous. See z/OS DFSMS: Using Data Sets“Optimizing Control Area Size,” for more information.STORCLAS(storage-class-name)For SMS-managed data sets: Gives the 1-to-8 character name of the storageclass. When possible, allow STORCLAS to default through the ACSroutines established by your storage administrator. Attributes assignedthrough storage class and the ACS routines replace storage attributes suchas UNIT and VOLUME. If SMS is not active, the system checks the syntaxand then ignores the STORCLAS parameter.TRTCH(C|E|ET|T)Selects the recording technique for 7-track tape as follows:CEData conversion with odd parity and no translation.Even parity with no translation and no conversion.46 z/OS V1R6.0 DFSMS Access Method Services for Catalogs