CA Dynam for VSE User Guide

Releasing Unused Disk Space
Single-Partition Volumes
You can also use the partition ID to uniquely define a volume serial number for
a particular partition. To do this, supply two hyphens ('--') as the last two
characters of the volume serial number on an EXTENT statement. For
example:
// JOB DEFINE PARTITION INDEPENDENT FILE
// DLBL SDDOUT,'==DISK.FILE(I,M)',2
// EXTENT SYS006,POOL--,1,0,1,8
// EXEC PROGRAM
CADD002I ALLOCATED FILE=SDDOUT SYS006=201 SYSWK1 X=0/3/8
CADD022I RELEASED 7 TRACKS FILE=SDDOUT VOL=SYSWK1
The partition ID substitution will occur before CA Dynam/D determines if the
volume serial number corresponds to a COMPOOL volume serial number.
Catalog-Defined Partition and CPU Independent Files
To use partition independence and CPU independence for catalog-controlled
data sets, you must first define each of those data sets separately in the
Catalog. Each possible combination must be defined as a unique entry in order
to maintain each file's allocation information.
The following example illustrates the DYNCAT DEFINE statements required. For
more information about the DEFINE command, see the chapter "Maintaining
The Catalog."
// JOB DEFINE
// EXEC DYNCAT
DEFINE'BG.CPU-A.IJSY01' DISK ALLOC=(POOL01,TRK,100)
DEFINE'F3.CPU-A.IJSY01' DISK ALLOC=(POOL01,TRK,100)
DEFINE'BG.CPU-B.IJSY01' DISK ALLOC=(POOL01,TRK,100)
DEFINE'F3.CPU-B.IJSY01' DISK ALLOC=(POOL01,TRK,100)
/*
/&
Releasing Unused Disk Space
This feature lets you recover significant amounts of disk space for subsequent
use. When a sequential disk (SD) file or an ISAM file is closed, CA Dynam/D
can truncate (release all unused space) allocated for the file. This facility is
standard for sequential disk files and is performed upon request for ISAM files.
However, only files allocated by CA Dynam/D are truncated.
4–40 User Guide