Main Storage (Memory) Requirements; Memory Space Requirements For Rbm; Memory Space Requirements For The Rbm Processors; Memory Space Requirements For User-Foreground Programs - Xerox 530 System Management Reference Manual

MAIN STORAGE (MEMORY) REQUIREMENTS
MEMORY SPACE REQUIREMENTS fOR RBM
The minimum RBM system, which would include keyboard/
printer, paper tape, and RAD I/O routines only, and pro-
vide aminimum number of RADde vice-files and operational
labels, requires about 500010 cells for the monitor and all
of its tables. This minimum memory space requirement
would increase as handlers are added for additional periph-
erals, as optional software routines are chosen (see Chapter 3)
during SYSGEN, and as additiona I devi ce-fi les, operational
labels, orPublic LibraryDEFs are allocated during SYSGEN.
The resi dence-space requi rements for RBM wi II vary from
5000 to 8000 cells, depending upon the user's configuration.
If background processing is desired, the user must allow an
additional minimum of 6000 cells for background space in
order to accommodate the RBM Job Control Processor, the
standard RBMsubsystems, and Extended Symbol.
MEMORY SPACE REQUIREMENTS fOR
THE RBM PROCESSORS
The memory space requi red for concurrent background pro-
cessing is a function of the longest overlay path of the set
of processors in question, p Ius the maximum work-space
and blocking-buffer requirement of that set. The standard
RBM language processors (Basic and ANS FORTRAN, and
Extended Symbol) require resident work space for symbol-
description tables during compi lation or assembly. Thus,
the number of source statements that can be processed in a
si ngle compi lation or assembly is di rectly proportional to
the amount of background memory avai lable over and above
the longest-overlay-path requirement.
All of the RBM processors are designed to uti lize memory
efficiently and will take advantage of any excess space
that may be avai lable. The performance of SORT, for
examp Ie, can be substantially enhanced by addition of
memory.
Tab Ie 2 shows the vari ous combi nati ons of processors that
are operable in the context of several samp Ie RBM/memory
confi g urati ons.
MEMORY SPACE REQUIREMENTS fOR
USER-fOREGROUND PROGRAMS
The amount of memory required for user-foreground programs
is the total size requirements for all concurrently resident
foreground programs and their blocking buffers, plus the
size of the nonresident foreground area if any.
The overhead for foreground tasks is 19 words per inter-
ruptible task, for the task control block and the task's PSD,
plus temp space as follows:
Monitor Services
Requirements
None
M:IOEX only
All services
Amount of Temp
Required
o
16
83
A restricted number of RBM services are avai lable with a
temp stack size of less than 83 words. (See "Monitor
Service Routines" in the RBM/RT, BP Reference Manual,
90 10 37.) Additional temp space is required if the tasks
are written in ANS FORTRAN IV and perform I/O.
Table 2. Processor Availability in Sample Configuration
T ota I Memory in System
RBM Configuration 16K 24K 32K
6K RBM, 1 K resident
9K BKGND 17K BKGND 25K BKGND
foreground, no non-
resident foreground, no All Processors except ANS A II Processors A II Processors
PUBUB.
FORT RAN and COBOL
6K RBM, 4K resident 6K BKGND 14K BKGND 22K BKGND
foreground, no non-
resident foreground, no JCP All Processors All Processors
PUBUB. RADEDIT except COBOL
UTILITY
XSYMBOL
OLOAD
8K RBM, 6K resident
(not oppli cable)
6K BKGND 14K BKGND
foreground, 2K non-
resident foreground, JCP
All Processors
2K PUBUB.
RADEDIT except COBOL
UTILITY
XSYMBOL
OLOAD
Mai n Storage (Memory) Requirements 5