April 1, 1981
In the payroll control module (PAYROLL), the subroutine DMSLADAD must
be called to establish the linkage to auxiliary directory. This
call must be executed before any call is made to a payroll module that
is in the PAYDIRT auxiliary directory.
LA R1, PLIST SVC 202 DC AL4 (ERRTN) PLIST DS OF DC CL8' DMSLADAD' DC V(PAYDIRT) DC F'O' Next, all payroll modules must have their absolute core-image files
generated and the payroll auxiliary directory must be initialized. In
the example, the payroll control module (PAYROLL) is given a mode number
of 2 while the other payroll modules are given a mode number of 1. When the PAYROLL program is finally executed, only the files on the 194 disk
with a mode number of 2 will be accessed. This means only the PAYROLL control program (which includes the payroll auxiliary directory) will be
referenced from the resident directory. All the other payroll modules,
because they have mode numbers of 1, will be referenced via the payroll
auxiliary directory.
The following sequence of commands will
core-image files for the payroll modules and
auxiliary directory. ACCESS 194 A
create the absolute
initialize the payroll LOAD PAYROLL PAYDIRT GENKOD PAYROLL (now the auxiliary directory is included in the
payroll control module, but it is not yet
ini tialized. ) LOADMOD PAYROLL INCLUDE PAYROLL1 GEN MOD PA YROLL 1 (this sequence of three commands is repeated fo
eacb payroll module called by PAYROLL.) LOADMOD PAYROLL INCLUDE PAYSHIFT GENMOD PAYSHIFT LOADMOD PAYROLL GENDIRT PAYDIRT Y GENMOD PAYROLL MODULE A2 When it is time to execute the PAYROLL program, the 194 disk must be
accessed as the Y disk (the same mode letter as specified on the GENDIRT
command). Also, the 194 disk is accessed in a way that includes the PAYROLL control program in the resident directory but not the other
payroll modules. This is done by specifying a mode number of 2 on the ACCESS command. ACCESS 194 Y/S * * Y2 NOW, a request for a payroll module, such
successfully fulfilled. The auxiliary directory PAYOVERT will be found on the Y disk.
as PAYOVERT, can be
will be searched and Ngte: A disk referred to by an auxiliary directory must be accessed as a
read-only disk.
322 IBM VM/370 System Programmer's Guide

Assembler Virtual Storage Requirements
The m1nlIDum 51ze virtual machine required by the assembler is bytes. However, better performance is generally achieved if
assembler is run in 320K bytes of virtual storage. This size
recommended for medium and large assemblies.
256K
the
is
If more virtual storage is allocated to the assembler, the size of
buffers and work space can be increased. The amount of storage
allocated to buffers and work space determines assembler speed and
capacity. Generally, as more storage is allocated to work space, larger
and more complex macro definitions can be handled. You can control the buffer sizes for the assembler utility data sets (SYSUT1, SYSUT2, and SYSUT3), and the size of the work space used during
macro processing, by specifying the BUFSIZE assembler option. Of the
storage given, the assembler first allocates storage for the ASSE8BLE and CMSLIB buffers according to the specifications in the DD statements
supplied by the FILEDEF for the data sets. It then allocates storage
for the modules of the assembler. The remainder of the virtual machine
is allocated to utility data set buffers and macro generation
dictionaries according to the BUFSIZE option specified: BUFSIZE(STD): 37 percent is allocated to buffers, and 63
work space. This is the default if you do
any BUFSIZE option.
percent to
not specify BUFSIZE(MIN): Each utility data set is allocated a single 790-byte
buffer. The remaining storage is allocated to work
space. This allows relatively complex macro definitions
to be processed in a given virtual machine size, but the
speed of the assembly is substantially reduced. Overlay Structures
An overlay structure can be created in CMS in two different ways,
although CMS has no overlay supervision. For descriptions of all the CMS commands mentioned, see the PRESTRUCTURED OVERLAY A prestructured overlay program is created using the LOAD, INCLUDE, and GENMOD commands. Each overlay phase or segment is a nonrelocatable
core-image module created by GENMOD. The phases may be brought into
storage with the LOADMOD command. Part 3. Conversational Monitor System (CMS) 323