Xerox 530 User manual

Xerox Real-Time Batch Monitor (RBM)
Xerox 530 and Sigma 2/3 Computers
System Management
Reference Manual
903036C

Xerox Corporation
701 South Aviation Boulevard
EI Segundo, California90245
213679-4511
Xerox Real-Time Batch Monitor (RBM]
© Xerox Corporation, 1973. 1975
Xerox 530 and Sigma 2/3 Computers
System Management
Reference Manual
903036C
January 1975
Pri ce: $2.00
XEROX
Printed in U.S.A.

REVISION
This publication is a revIsIon of the Xerox Real-Time Batch Monitor (RBM) System Management Reference
Manual for Xerox 530 and Sigma 2/3 Computers, Publication Number 90 30 36B (dated March 1974). This revision
incorporates changes that reflect version GOO of the RBM system.
RELATED PUBLICATIONS
Xerox 530 Computer/Reference Manual
Xerox Sigma 2 Computer/Reference ManuaI
Xerox Sigma 3 Computer/Reference Manual
Xerox Availability Features/Reference Manual (Xerox 530 and Sigma 2/3)
Xerox Real-Time Batch Monitor (RBM)/RT and BP Reference Manual
Xerox Real-Time Batch Monitor (RBM)/OPS Reference Manual
Xerox Reaf-Time Batch Monitor (RBM)/User's Guide
Xerox Real-Time Batch Monitor (RBM)/System Technical Manual
Xerox Extended Symbol/LN,OPS Reference Manual
Xerox Symbol/LN,OPS Reference Manual
Xerox Basic FORTRAN and Basic FORTRAN IV/LN Reference Manual
Xerox Basic FORTRAN/OPS Reference Manual
Xerox Basic FORTRAN IV/OPS Reference Manual
Xerox FORTRAN/Library Technical Manual
Xerox ANS FORTRAN IV/LN Reference Manual
Xerox ANS FORTRAN IV/OPS Reference Manual
Xerox Sort/Reference Manual
Xerox Report Program Generator (RPG)/Reference Manual
Xerox ANS
COBOL/LN,OPS Reference Manual
Publication No.
90 19 60
900964
90 15 92
9030 54
901037
90 15 55
90 17 85
90 11 53
90 10 52
90 10 51
900967
90 10 61
90 15 25
90 10 36
90 18 06
90 18 07
90 17 87
90 18 41
9030 90
Manual Content Codes: BP -batch processing, LN -language, OPS - operations, RP -remote processing,
RT - real-time, SM -system management, TS - time-sharing, UT - utilities.
The specifications of the software system described in this publication are subject to change without notice. The availability or performance of some features
may depend on a specific configuration of equ ipment such as additional tape units or larger memory. Customers should consult their Xerox sales representative
for detai Is.
ii

CONTENTS
COMMAND SYNTAX NOTATION
v
Optional Foreground FaciI ities
15
Symbiont
Plotting System 15
Character-Oriented Communications
l.
I NT RODUCTI ON
Program (RCOC)
17
System Interface Un it Handlers
17
Scope and Purpose of this Manual Background Processor Memory Requi rements
17
Organization of the Manual
Disk Storage Allocation Guidelines
18
Availability Features
Disk Allocation Summary 18
Remote
Assistance
1
SYSGEN Disk-Allocation Parameters
18
Error Logging 2
Master Dictionary Formation
20
SYSERR Analysis 2 Expl
icit Area Allocation
20
Device Isolation
2
Default Area Allocation
21
On-Line Device Exercises 2
Area Write Protection
23
2.
HARDWARE CONFIGURA nON GUIDELI NES
3
4.
SYSTEM GENERATION
24
Introduction
3
Introduction
24
Hardware Interrupt Requirements 3
SYSGEN Functional
Overview 24
Main Storage (Memory) Requirements 5
Operational Overview
24
Memory Space Requirements for RBM
5
System-Release Tape Format 25
Memory Space Requ irements for the Defin
ition-Phase Operation 25
RBM Processors 5
loading SYSGEN
25
Memory Space Requirements for User-
Input Parameters
27
Foreground Programs 5
General Syntax of Input
Secondary Storage Requi rements 6 Parameters
27
RBM Secondary Storage Requirements 6
Definition Phase Output
37
User Secondary Storage Requirements 6 Messages
to the Operator
37
Removable Disk Packs and Cartridges 6 SYSlOAD-Phase Operations
38
Area Definition and Pack/Cartridge ALL Option
39
Initialization 6 RBM Symbol Map 40
Pack/Cartridge Mounting 6 UPD (Update) Option 41
Peripheral Equipment Requirements and System
load Phase Error Messages 41
Options 8
Keyboard/Printer -Required 8
Character-Oriented Commun ications
5.
LOADING RBM SYSTEM PROCESSORS 43
(COC) - Optional 8
Plotter Symbiont '- Optional
9
SystemStartup and Processor loading 43
Xerox Satell ite Processor - Optional ___
9 Saving the New System
43
Basic Spooling System - Optional
9 Additional RBM Processors
43
Additional Peri pheral Options
9 RBM Maintenance/Util ity Processors
43
Miscellaneous Hardware Options 9 Other RBMProcessors
44
Sigma 3 Extended Arithmetic -Loading RBM Maintenance/Uti lity
Model 8119
9 Processors
44
Xerox 530 Hardware Floating-Point -
Model 4118 9
6.
SYSTEM MAINTE NANCE
45
3.
SOFTWARE CONFIGURATION GUIDELINES 10
Introduction
45
Hardware/Software Requ irements 45
Introduction 10 Hardware Requirements
45
Main Memory Allocation
10 Software Requ i
rements
45
Resident RBM Modules 10
SYSGEN Considerations
45
Nonoptional Resident Modules 10 Ma.intenance
Procedures
46
Optional Resident Modules 10 RBM Module Update Procedure
46
Resident I/O Tables and Routines 13 RBM Overlay Replacement
46
File Control Table Allocation 13 Replace Operations
46
Operational Label Assignments 13 Replace Diagnostics
47
Nonresident RBM Modules
15
Repl ace Operator Messages
47
iii

Generation of SYSGE N Input Tape
47
TABLES
Hexadecimal Patching Procedure for
RBM Modules
48
l.
Model 530/Sigma 3 Interrupt-Structure Comparison_
4
Hexadecimal Patching Procedure for
2.
Processor Avai labi lity in Sample Configuration __
5
Processors
48
3.
Comparison of Secondary Storage Devices 7
Method for Magneti c Tape 49
4.
I/O Table and Routine Increments by
Method for Punched Cards
49 Device Type 14
Method for Paper Tape
49
5.
Nonresident RBM Modules
15
6. Standard SIU Handlers 17
INDEX
7.
Background Processor and Subsystem
Requirements
18
8.
Disk Data Organization
18
FIGURES
9.
System-Disk Storage Summary 19
10. Spooling Volume Requirements 20
1.
RBM Lowest-Cost, Minimum Configuration 3
11.
Defau It Area Allocations 22
2.
RBM Typical Configuration
4 12. SYSGEN Input Options and Parameters 27
3.
RBM Disk File Management 8 13. I/O Device Model Numbers 37
4.
RBM Memory AI location Example
11
14. SYSGEN Error Messages 38
5.
Background Memory Usage Example 12 15. System-Load Phase Error Messages 42
6. System Release Tape Format
26
16.
REPLACE Diagnostics
47
7.
Hex Patching Input Example
48
17.
RE PLACE Operator Messages 47
iv

COMMAND SYNTAX NOTATION
Notation conventions used in command specifications and examples throughout this manual are listed below.
Notation
lowercase letters
CAPITAL lETTERS
[]
{}
Numbers and
special characters
Subscripts
Description
Lowercase
letters identify an element that must be replaced with a
user-selected value.
CRndd
could be entered as CRA03.
Capital letters must be entered as shown for input, and wi II be printed as shown
in
output.
DPndd means lIenter
DP followed by the values for ndd
ll
•
An element inside brackets is optional. Several elements placed one under the
other inside a pair of brackets means that the user may select anyone or none of
those elements.
[KEYM] means
the term II KEYM II may be entered.
Elements placed one under the other inside a pair of braces identify a re-
quired choice.
{~}
means that either the letter A or the value of id must be
entered.
The horizontal ellipsis indicates that a previous bracketed element may be re-
peated, or that elements have been omitted.
nameG name]. .. means that one or more name values may be entered,
with a comma inserted between each name value.
The vertical ellipsis indicates that commands or instructions have been
omitted.
MASK2 DATA,2 XllEFI
BYTE DA T A, 3 BA (L(59))
means
that there are one or more state-
ments omitted between the two DATA
directives.
Numbers that appear on the line (i. e., not subscripts), special symbols, and
punctuation marks other than dotted lines, brackets, braces, and underlines
appear as shown in output messages and must be entered as shown when input.
(value) means that the proper value must be entered enclosed in
parentheses; e. g., (234).
Subscripts
indicate a first, second, etc., representation of a parameter that
has a different value for each occurrence.
sysid1, sysid2' sysid3 means that three successive values for sysid
should be entered, separated by commas.
v

1. INTRODUCTION
SCOPE AND PURPOSE OF THIS MANUAL
The information in this manual falls into three general
areas, as fol lows:
• Hardware and software configuration planning.
• System
generation and initialization.
• System
maintenance.
The intended readership of this manual falls, correspond-
ingly, into three major categories.
• Installation management, responsible for planning the
functional capabilities of the desired RBM system and
for selecting a hardware configuration to best satisfy
the installation's requ irements.
• System programming staff, responsible for designing the
installation-specific system generation and initializa-
tion procedures required to achieve an operational
system, and for formu lating any post-generation main-
tenance that may be necessa ry •
• Senior operations personnel, responsible for performing
the system generation, initial ization, and maintenance
procedures.
ORGANIZATION OF THE MANUAL
The present chapter, in addition .to providing an intro-
duction to the manual, presents an overview of the Xerox
Availability Features of the RBM system. These features
are designed to complement the salient reliability and
maintainability characteristics of the hardware. (See the
Xerox Availability Features/Reference Manual, 90 30 54,
for detailed usage descriptions of the Availabi lity Features. )
The
succeeding chapters are organized as follows:
• Chapter 2 presents guidelines for the selection of a
desirable hardware configuration in terms of perform-
ance requirements, application suitability, data-band-
width considerations, etc. For example, guidelines
are given for selection of the size of main storage, and
the size and type of secondary storage, appropriate to
the user's specific needs.
• Chapter 3 presents both guidelines for software con-
figuration planning (supplementing the information in
Chapter 2 in this regard) and detailed information on
designing a specific system generation procedure for
the desired system. .
•
Chapter 4 presents the operational aspect of system
generation (SYSGEN), i.e., directions for performing
the SYSGEN process.
• Chapter 5 presents system initialization information;
that is, it gives directions for adding desired processors,
Iibraries, resident foreground programs, etc., to the
newly generated monitor so as to ach ieve a fu lIy op-
erationa I RBM system.
• Chapter 6 gives system maintenance information and
procedures: how to temporari Iy or permanently replace
RBM modules with newer or modified versions; how to
patch RBM, subsystems, and processors; how to prepare
a modified SYSGEN input tape; etc.
AVAILABILITY FEATURES
The Availability Features provided with RBM are designed to
streamline maintenance activities and reduce maintenance
down-time. These features are error logging, SYSERR anal-
ysis, device isolation, and on-line device verification. The
Avai labil
ity Features can be used by on-site customer per-
sonnel as well as (in the case of the Model 530) by remotely-
located Xerox maintenance experts, via the Xerox Remote
Assistance
interface. These features enable the user to in-
teract more effectively with the system to increase "up-time"
availabil ity.
User sites at which remote assistance is not available still
benefit by the use of the information gathered by automatic
error logging during system operation. The other features
are of course also usable whenever customer personnel or a
Xerox system
specialist is on-site (assuming provision for
these features during system generation).
Note that Xerox Remote Assistance is applicable only to
Model
530 systems. All of the availability features other-
wise apply without restriction to all RBM users.
See the Xerox Availability Features/Reference Manual,
90 30 54, for full descriptions.
REMOTE ASSISTANCE
The Xerox 530 Remote Assistance feature, in conjunction
with the use of error logging and SYSERR analysis, permits
operator-attended sites to be examined by a system special-
ist without his having to make a trip to the site. He can
monitor the transactions at the operator's console from his
remote
console. He can examine a SYSERR analysis print-
out and selectively interrogate the error log. He can
detect a pattern of error buildup for an I/o device, as seen
in the error log, facilitating proper maintenance scheduling
and increased ava ilabiiity . He can even "Iook over the
shoulder" of a Xerox Customer Engineer or of a site operator
during device isolation and exercise, all whi Ie RBM is pro-
cessing normal production tasks.
Introduction

This remote-assistance capabi lity allows for assignment of
the proper level of aid to a problem at the earliest possible
moment and permits customer self-help in increasing system
availability.
ERROR LOGGING
RBM provides hardware error detection and the automatic
logging of such errors to a special file. This error-log file
then serves as a history of errors that may be analyzed and
listed by an on-line program (in chronological or sorted
order) for use by customer or Xerox maintenance personnel.
Query of the error log reveals the quantity and type of
errors, frequency of occurrence, and the distribution of
device status reported at time of error. Analysis of error-
frequency changes and other factors leads to schedu ling of
maintenance prior to actual failure, and lessens the time
required for analysis and correction of unpredicted fai lures.
Sites that use this feature provide Xerox with an error-log
database to be examined during scheduled or unscheduled
maintenance. Whether the system special ist is using
Remote
Assistance or is actually at the site, he takes
advantage of the error log summary, sorted listing, and
chronological listing to maintain the system and increase
its avai labiI ity. The user's operations personnel can also
benefit by the error-log summary by using it to monitor
their system's performance over a period of time.
SYSERR ANALYSIS
RBM provides the capability to obtain a formatted represen-
tation of the internal state of system tables and contents of
memory. The displayed data is segregated and labeled as
to significance. This provides the local or remote Xerox
system specialist (or the user) with a simplified means of
seeing and understanding abnormal system states without
having to decipher a raw hexadecimal dump. It is espe-
cially useful in reducing the time required to isolate prob-
lems that can be detected by their effect upon system-table
data.
The format of output is optimized for display on line
printers, but may be displayed on other devices. In fact,
the Remote Assistance system specialist expects to analyze
such displays at his console, as one of his most valuable re-
mote problem-solving tools.
2 Avai labi Iity Features
DEVICE ISOlATION
Noncritical devices th~t are known to be faulty or considered
to be marginal can be isolated from the system by operator
control. Whi Ie the device is being exercised, repaired, or
replaced, RBM continues to operate any programs that do
not mandatorily and specifically require that particular de-
vice. Thus, in many cases the system is now stiII avai lable
when formerly it wou Id have been "down". The on-I ine de-
vice exerciser tests (described below) may be run only on
devices that have been so isolated (i.e., made unavai lable
to normal access).
RBM allows device-address substitution between devices of
the same model number (except for disk devices). This
permits, for example, switching (by means of an operator
key-in) from one magnetic tape drive to another of the same
type.
ON-LINE DEVICE EXERCISERS
Prior to exercise, a device is isolated from normal system
use, via the local or remote-assistance console. Then the
device exercisers (to the exclusion of any other programs)
operate the device, verifying its functional capabi Iity and
recording any errors in the error log. Upon completion of
such a device test, a device status message is printed at the
operator's console to indicate whether or not the device is
capable of operating within normal service requirements. If
so,
the device becomes eligible for return to the system. A
device that fails to pass these tests should be scheduled for
maintenance.
The exercisers are not designed to diagnose the device at
the component level. Rather, they exercise the device's
functional capabilities in the user environment (without
interfering with the operation of RBM with respect to its
other functions). Recoverable errors are seen by examina-
tion of the error log, while irrecoverable errors cause the
exerciser to report that the device did not pass the testing.
One appropriate use of the on-line device exercisers is to
check the assumed operational reliability of a device that
has just undergone maintenance or repair, prior to returning
it to normal service.

2. HARDWARE CONFIGURATION GUIDELINES
INTRODUCTION
This chapter is intended as an aid to the system manager in
selecting the proper hardware for his RBM system. A
reasonable selection of hardware can be made only on the
basis of a thorough understanding of the particular applica-
tion's requirements. Requirements that must be evaluated
include the number of discrete interrupt leve Is required,
the amount of secondary storage required for programs and
data, memory requirements to satisfy resident foreground
needs and concurrent batch (if desired), and peripheral
equipment requirements for the data media desired. Figure
illustrates the lowest-cost minimum RBM configuration.
Figure 2 illustrates a more typical RBM configuration.
HARDWARE INTERRUPT REQUIREMENTS
The maximum number of foreground tasks that are expected
to operate concurrently determines the number of hardware-
interrupt levels required, in addition to those needed by
RBM itself. The association of an interrupt level with a
task
establishes the priority of the task. The task's worst-
case response time (to an external stimulus) is dependent
upon the maximum RBM inhibit time and the possible activity
of higher priority tasks. Tasks that are prioritized above
Core Memory (8K)
Memory
Protect
Power Fai I Safe
Xerox
Extended Arithmetic
530
CPU
Multiply;'bivide
4101
Integral Interrupts (6)
Real- Time Clocks (2)
lOP with 16 channels
Keyboard Printer Control
~
~
r:
Remote
(KSR-33) Assistance
Interface
the I/O interrupt task must contend only with the RBM
maximum inhibit of 100~ec and possible interference among
themseI
ves.
The standard Xerox 530 is equipped with two interrupt levels,
Integral 5 and Integral 6, thatare higher in priority than the
I/o interrupt task. (Sigma 2/3 can have a larger number of
these. ) Tasks associated with an interrupt priority higher than
I/O cannot utilize any RBM services that involve I/o; thus
these higher interrupt levels are typically associated with
high priority tasks that utiI ize the Direct I/o interface with
SIUs and defer RBMservices to related, lower-priority tasks.
Tasks
that operate at a priority lower than the I/O interrupt
level can utilize all RBM services including I/O. Any num-
ber of these tasks may operate concurrently up to the number
of available lower-priority hardware inter:rupts minus one.
(The RBM Control Task requires the lowest-priority hardware
interrupt level actually utiI ized in the system.) For tasks
below the I/O level, the I/o interrupt can cause an inter-
ference of up to approximately 500 microseconds, however
since I/O interrupts can stack up, the interference can be
extended in order to service all pending interrupts.
The same hardware interrupt can be used "serially" by
different tasks, but on Iy one can be connected to a given
interrupt at anyone time. Table 1 gives a comparison of
the Sigma 3 and 530 interrupt structures.
4151
Core Memory
(8K)
f""'"
~
'-
..,..
7250
7251
Disk
Controller
(2.3 mb)
-"
Binary
Input
Device
Figure 1. RBM Lowest-Cost, Minimum Configuration
Hardware Configuration Guidelines 3

Xerox
530
CPU
4101
Computer
530
Sigma 3
Notes:
l.
2.
Core Memory (8K)
Memory
Protect
Power Fai I Safe
Extended Arithmetic
Multiply,/Divide
Integral Interrupts (6)
Plus 4125 External Interrupts (12)
Real-Time Clocks (2)
lOP with 16 Channe Is
Plus 4105 two-Byte Interface
Keyboard Printer Control
l..----
~3
l .~~33)
~
Remote
Assistance
Interface
4151
4151
8K Memory 8K Memory
I
3451
line
Printer
~
7250
Disk Controller
7121
-
Card Reader
,-------to
8
Figure 2. RBM Typical Configuration
Table 1. Model 530/Sigma 3 Interrupt-Structure Comparison
Maximum
No. of
1
External Interrupts Clocks Priority
Levels> I/O
30, standard and
2 standard 2 standard
optional combined.
100, all optional 4 optional
100 opti ona I
-
4151
8K Memory
1
,,-- ~
r"o..... ./
7251
(2.3 mb)
'- ~
7251
(2.3 mb)
'- ~
Priority Levels < 1/0
2
4 standard,
24 optional
100 optional
Clock 1, set at a frequency of 500 Hz, is typically dedicated to provide RBM services relating to I/o
timeouts, job accounting, and background-execution-time limit.
There is a SYSGE N override
(ClK1FREQ,0); therefore, an installation may choose to forego these facilities in favor of real-time
usage of Clock 1. This should not be necessary however, since a Clock 1 receiver is provided.
RBM requires
that
the
lowest-priority hardware interrupt leveI be dedi cated to the RBM Control
Task.
4 Hardware
Interrupt Requirements

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 Idevi 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
exampIe,
can be substantially enhanced by addition of
memory.
Tab
Ie 2 shows the various combi nati ons of processors that
are operable in the context of several samp Ie RBM/memory
configurations.
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, 1K 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
Main Storage (Memory) Requirements 5

The following tab Ie provides an indi cation of the additiona I
temp-space requirements of AN5 FORTRAN IV foreground
programs
that perform I/O:
Sequential 1'0
Direct Access I 0
320x or 323x 720x or 725x 7232 or
724"
--,,----
,-
Binary Formatted Binary Formatted Binary Formatted Bi nary Formatted
--
,-
76-112
131-167 170
225 222 277
554
609
words words words words words words words words
Blocking buffers are required for each operational label (or
FORTRAN device number)that is associated with a blocked
disk file. The blocking buffer sizes are as follows:
320x or 323x 720x
or 725x
7232 or 724x
128 words 180 words
512 words
If
nonresident foreground tasks are desired, a separate non-
resident foreground partition - contiguous with background
at its upper boundary -must be defi ned at SYSG EN. The
nonresident foreground area may be as small as K:BlOCK +
17 words as allowance for background TCB.
Note that a large nonresident foreground program wi II auto-
matically cause a checkpoint of background if it extends
into the background area. Thus it is not necessary to de-
fi ne a nonres ident parti tion that wi II accommodate the
largest possible nonresident forground program, but rather
only one large enough to contain the largest nonresident
program that must coexist with background programs.
SECONDARY STORAGE REQUIREMENTS
The optimal type of secondary storage for an RBM system is
dependent upon the requirements of the installation. The
storage capacity required may dictate the use of disk packs,
or perhaps where access time is very important and the
majori ty of transfers are smaII, a 320x RAD wou Id be appro-
priate. (Note that for small average-transfer sizes on the
order of 500-1000 bytes, access time is more critical than
transfer rate.)
Although RBM does not require magnetic tape, it provides
optimum
backup capabi lity for RAD and disk packs as well
as providing on-line, bulk-data I/O. Table 3 gives a com-
parison of the access time, capacity, and other pertinent
characteristics of the various secondary storage devices
supported by RBM.
The amount of secondary storage required for an RBM system
is a
function of the secondary storage requirements of RBM
itself, plus user requirements for program and data storage,
plus background temporary fi Ie space.
6 SecQndary Storage Requi rements
RBM SECONDARY STORAGE REQUIREMENTS
If a user wants to have al I the system processors and a com-
plete system library stored on the disk and wants to al locate
enough Background Temp area to assemble an average
5000-line source program, approximately .56 megabytes of
disk storage would be needed for the system. (The smallest
Xerox RAD unit, Model 7202, has a .75-megabyte storage
capacity.)
USER SECONDARY STORAGE REQUIRE MENTS
Figure 3 illustrates the hierarchy of RBM fi Ie management.
It is important to note that since a file may not span phys-
ical devices boundaries, the capacity of secondary storage
devi ces at an insta IIation may Iimit the maxi mum fi Ie size.
This is especially important to consider for RPG and COBOL
ISAM data bases, since the entire data base must be con-
tained within one file.
The 50 RT processor a Iso requires disk space for sorting;
the amount of disk space required is approximate Iy 2.2 times
the
input file size. This intermediate disk storage may be
divided into two fi les, each on a separate device, to pro-
vice for faster sorts and also to accommodate larger input
fi les.
It is also important to note in this regard that blocked fi les
(packed random, blocked sequential, or compressed) require
use of a blocking buffer. Extensive usage of blocked fi les
on 724x disk
packs may involve an additional core require-
ment due to the large sector size (1024 bytes) and the con-
sequently large blocking buffer size. RBM does have a
provision for
defining a blocking buffer size of less than
1024bytes for 724x disk pack systems. This, however, is waste-
ful of diskspace, the feature being provided merelyas a con-
version aid for installations upgrading to a 724x configuration.
REMOVABLE DISK PACKS AND CARTRIDGES
AREA DEFINITION AND PACK/CARTRIDGE
INITIAlIZA TION
Each disk can be divided into from 1 to 16 areas. Re-
movable disk packs are initialized by the RAD Editor.
The
RAD Editor writes a Volume Table of Contents (VTOC)
onto the pack/cartridge, which contains the serial num-
ber of the disk pack/cartridge and the area descriptors
of the areas contained on that disk pack/cartridge. The
pock/cartridge may be mounted on any available spindle
through use of the M (Mount) key-in. (Packs/cartridges
to be permanently mounted on a given spindle are initial-
ized at 5YSGE N during Disk Allocation; see Chapter 3. )
PACK/CARTRIDGE MOUNTING
The Mount key-in specifies the areas to be mounted or
directs that all areas on that disk pack/cartridge to be
mounted. In either event, the core-resident Master Die-
ti onary wi II be updated to indicate the areas mou nted.

Device
3203 I
3204
32319
32324
,9
3325
3335
7202
7203
7204
7232
72463
,9
72514
7315/16
7362
7372
Notes:
-----
Table 3. Comparison of Secondary Storage Devices
lOP Bandwidth2 Requirements
Sigma 3
1 Average Maximum Blocking
Capacity
Access Time Transfer Rate
530
IIOP EIOP Buffer
Size
1.3 mb
8.5 ms
755.2 kb
100%8 NA
NA
128 words
2.6 mb
8.5 ms
755.2 kb
100%8 NA NA 128 words
2.4 mb
50 ms
312 kb
36% NA
NA
128 words
4.9mb
50 ms
312 kb 36%
NA NA 128 words
23mb (l'80<hpi5
8.8 ms 36 kb 6% NA NA NA
46mb rt1600bpi5
B.8 ms
72 kb
11% NA NA
NA
.75 mb
16.9 ms
187.5 kb 45%
35% 35% 180 words
1.5 mb
16.9 ms
187.5 kb 45%
35% 35%
180 words
3.0 mb
16.9 ms 187.5 kb
45% 35%
35%
180 words
6.3 mb
16.9 ms 384 kb NA
78% 72%-600k 512 words
24.5 mb
87.5 ms 312 kb
77%-52% 59%
59%-49%
512 words
2.3 mb
50.5 ms 312 kb
78%-57%
NA NA 180 words
23mb U80<hpi5
5rns
60 kb
18% 13% 13%
NA
. 16mb u556bpi5
1O.n1s
20 kb
8%
7% 7% NA
23mb u80Obpi5, 6 5
ms
60kb
7
NA
12% 12% NA
1. RBM requires approximately .36-.56 megabytes for system storage, including standard processors.
2. RBMdoes not manage bandwidth control, thus the installation must be properly configured to avoid
data overruns~ When two figures are shown, the second figure indicates bandwidth requirements
when the
two-byte interface is included; this figure is not shown if not applicable. .
3. RBM treats each 7242 as two 7246 disk packs. All disk packs except the system-residence pack
may be declared to be removable.
4. Each 7252 is treated as two 7251 devices. Each j13.;·) is treated as two 3232 devices.
5. Assuming 240D-foot reels andnointerrecord gaps. Reduce this figure by the percentage of
the tape required for interrecord gaps. This value is a function of record size since gap is
fixed (0.75 inches for 7362/72; 0.5 to 0.75 inches (average 0.6 inches) for 7315/16; 0.6
inches for 3325/35).
6. Model 7372 transfers six bits of information. per byte.
7. Model 7372: reduce transfer rate by 25 percent for packed binary mode.
8. Requires
dedicated IOP2.
9. Any device controller which is capable of performing seek overlap cannot share a channel
with any other device controller.
Secondary Storage Requirements 7

Master Dictionary
(in memory)
Areal
Area
n
The following rules apply:
Physical
Devi ce (pock or RAD)
/
/
/
/
/
r--
\ \ \ \
/
/
/
r--
-
~
...
\ \
Areal
Lobel
First Fi Ie
Directory Entry
f-- - -
----
Entry a
r-------
Entry b
~------
File
a
Fileb
Areal File
Directory
• A physical device (e.g., a RAD) may contain 1 to 40 areas. An area is totally contained on
one physical device.
• An area may contain one or more files. A file is totally contained within one area.
Figure 3. RBM Disk File Management
sufficient spare entries must be available in the Master
Dictionary to accommodate the newly mounted areas, and
the areas to be mounted must be uniqueIy named among
those
areas already mounted. RBM performs the necessary
checks
to ensure proper mounting.
Special precaution must be taken for 7252 and 3233 Car-
tridge Disk units. Since the fixed disk as well as the re-
movable disk is stopped when replacing the cartridge, at!
file activity must be quiesced for both the fixed and re-
movable portions of the device (which are independently
addressable). If RBM's SP area resides on the fixed disk,
the computer must be placed in a completely idle state
(no active background or foreground, no key-ins pending).
Failure to do so will result in a SYSERR with code SP when
on attempt is mode by RBM to access an overlay. Fore-
ground tasks that access files on the fixed portion of a drive
may also require the computer to be in the idle state to
avoid the Inonoperational
l
condition. Obviously a crit-
ical real-time environment cannot tolerate the computer
being in lidle I, therefore, proper allocation of areas and
spindles is essential (e.g., two 7251 devices may be re-
qu ired rather than a single 7252).
8 Peripheral Equipment Requirements and Options
PERIPHERAL EQUIPMENT REQUIREMENTS AND OPTIONS
KEYBOARD/PRINTER - REQUIRED
RBM requires that the minimum configuration include a
keyboard/printer for operator control.
If an installation is configured with two or more keyboard/
printers, it is strongly suggested that OF N 1, which must
reference a keyboard/printer, pointat the same printer used
for
background operations. Foreground tasks that reference
a keyboard/printer should not reference the keyboard/printer
associated with OF N t.
CHARACTER-ORIENTED COMMUNICATIONS (COC)-
OPTIONAL
• One buffered input/output channel dedicated to a
7630 Controller, with eight lines.
• External DIO interface feature (Model 4170 for
Xerox
530, Model 8170 for Sigma 3).
• Two external interrupts dedicated to the cac controller.

The COC software support (Catalog No. 705719) requires
approximate
Iy 1K words of resident memory space.
PLOTTER SYMBIONT - OPTIONAL
• One interrupt level reserved for symbiont usage.
• Model 7530 or 7531 graph plotter.
The plott~r software support requires approximately 1Kwords
of resident memory space. Approximate Iy .06 megabyte of
secondary storage is required foreach eight minutes of out-
put backlog desired.
XEROX SATELLITE PROCESSOR- OPTIONAL
•
One interrupt level is required for basic scheduling and
local operations. .
•
One interrupt level is requiredforremote communication.
• Model 7605 synchronous controller -full or half
duplex -with proper code set (IBM EBCDIC but with
ACKO replacing ACK).
•
2000-19,200 bps modem (higher or' lower speeds requi.re
appro~ed field request).
Satellite processor core requirements are a function of
line and peripheral speeds. Refer to the printed descrip-
tion 706491-11 for complete information. A rough rule
of thumb woul.d be to allow 8.4K for full remote oper-
ation of four streams at 9600 bps and 5K if only local/
local operation is desired (see Chapter' 3, Table 10 for
spooling
requ~rements). .
BASIC SPOOLING SYSTEM - OPTIONAL
• One interrupt level is required for each active copy
of BSS.
The basic spool ing system requires approximately 1 K, plus
buffer
space, for each active copy of BSS (see Chapter 3,
Table 10 for spooling requirements).
ADDITIONAL PERIPHERAL OPTIONS
Consult Chapter 3 for details about other optional periph-
eraJ devices supported by RBM, and their memory space
requirements for device handlers.
MISCELLANEOUS HARDWARE OPTIONS
SIGMA 3 EXTENDED ARITHMETIC -MODEL 8119
This
feature provides hardware multiply and divide and
multiple-precision mode instructions. This option is re-
quired for RPG and COBOL.
XEROX 530 HARDWARE FLOATING-POINT -
MODEL 4118
This feature, in conjunction with rhe ANS FORTRAN li-
brary routines that utilize the floating-point instructions,
will provide a substantial performance improvement for
FORTRAN programs. Perforrriance improvement relative
to software floating-point for a compute-bound test pro-
. gram has been measured at a 2.2 : 1 ratio. (The program
used for
the test is an actual program in commercial use for
data reduction and analysis. )
Miscellaneous Hardware Options 9

3. SOFTWARE CONFIGURATION GUIDELINES
INTRODUCTION
This chapter is intended as an aid to the system manager in
defining the system generation parameters that are required
to create an RBM system optimized for itsspecifi c applica-
tion environment. The two primary aspects of "tailorable"
system resources are main memory and secondary (disk)
storage.
MAIN MEMORY ALLOCATION
Moin memory is al located in the fol lowing manner (and as
illustrated in Figure 4):
1. The fi rst 256 words in lower memory (the zero table)
are reserved for constants and pointers.
2. The region from 256 to 399 (decimal) is reserved for
internal and external interrupt levels; any space not
required for interrupt levels wi II be used by the Moni-
tor for tab Ie space.
3. The remainder of memory is allocated as follows=
a. Resident RBM, to be loaded beginning at location
400 (decimal) and to include only those opti onal
routines selected by SYSGEN.
b. Public Library (if allocated).
c. Resident foreground (if allocated).
d. Nonresident foreground (if allocated).
e. Background. At least 256 words must be allo-
cated whether or not batch is required; minimum
useful amount allocated should be the length of
the Job Control Processor (6000 words decimal)
(see Figure 5).
4. No foreground space need be a I located for a batch-
onIy system.
The user
should decide which of the areas described under
item 3, above, are more apt to need additional space in
future and make allocations accordingly. A given area
could then be expanded downward in a future SYSGEN,
into unused area space below it, and only the programs in
the reallocated area would have to be reloaded, not the
entire system. (In Figure 4, for example, the resident
foreground might expand into the unused Public Library
area. )
RESIDENT RBM MODULES
RBM consists of both resident and nonresident modules.
Resident modules consist of functions that are frequently
10 Software Configuration Guidelines
used or which must quickly react to internal or external
events. Nonresident modules consist of functions that are
infrequently used or for which immediate response is not
necessary. Resident modu fes consume memory space as
the price for rapid response to internal/external events.
Nonresident modules consume response time as the pri ce for
memory
space ava; lability.
Since the user has the option to select whether certain
modules are to be resident or nonresident, this chapter is
intended to provide the information necessary to make
tradeoff deci sions between memory space and response time
when either resource is critical to system performance.
NONOPTIONAL RESIDENT MODULES
The following RBM functions are unconditionally inc luded
as resident in memory. All sizes are approximate unless
otherwise specified .
Size (decimal)
Function
Constants, pointers, transfer
vectors, interrupts, etc.
Fixed tables and nonresident-
over lay area.
Min.
275
575
(See "Resident
Max.
400
575
I/()
Vari able tables (i ncluding
TVECT). Tables
and Routines ")
Integer Multiply;bi vide
Simulation.
I/() Interrupt Task.
PCP
Interrupt Task and RBM
Control Task.
Machine Fault Task
Sigma 2 = 50
Sigma 3 = 100
Model
530 = 200
Service Routines
Total Nonoptional
(v represents variable tables)
0
300
150
50
2500
3850+v
OPTIONAL RESIDENT MODULES
175
300
150
200
2600
4440+v
The following RBM functions are included as resident in
memory
if selected as an optional feature during SYSGEN.
Selection
Keyword
Function
Size
PR()TECT Protection Task 75
P()WE R Power ()n-()ff Tasks 250
E P.R()RSUM li() Error and Use Count 25+4* I/O channe Is

(K:PLFWA
)-
(K:RFFWA
)-
P
rotected
(K:NFFWA)-
(K:BACKP) -
(K:BACKBG)
Unp
rotected
(K:UNAVBG)
low Memory
Zero
Table:
constants and pointers
dedicated interrupt locations
RBM I/o tables and overlay region
Selectable, optional RBM routines
RBM patch area
Transfer Vector Table
Publ ic library
Unused Publ ic Library area
Real-ti me task 1 temp stack
Task Control Block 1
Rea I-ti me task 1
Real-time task 2 temp stack
Task Control Block 2
Real-time task 2
Special end-action I/o routine
Foreground program A COMMON area
Real-time task n temp stack
Task Control Block n
Rea
I-ti me task n
1
RBM
1
Resident
Fo reground Program A
Addition
01 Resident
ndForegrou
I
Nonresi dent
Foregrou
nd
Space
Blocking buffer for loading foreground programs
Background
TC B
Background temp
stack
User main program Backgrou
nd
)
User subprograms
Li brary subprograms
Blank
COMMON (if any)
,
High Memory
Figure
4. RBM Memory Allocation Example
RBM Memory Allocation Example 11

Low Memory
t
Protected
1
Unprotected
High Memory
Background TCB, without PSD
Floating accumulator (5 locations)
FORTRAN I/O format information
Allocated temporary space
Unallocated (as yet) temporary
space for Public Library and
monitor service routine use.
User program and subprograms
(including any I ibrary routines
not in the Publ ic Li brary)
Unused space
Disk I/O blocking buffers
(From 1 to 16 buffers;
si ze of
buffer determined at SYSGEN)
Blank COMMON (if any)
(Unavailable memory, if any)
Figure 5. Background Memory Usage Example
12 Background Memory
Usage Example
(K:BACKP)
(K:BACKBG), (K:BASE)
TEMPBASE+6
K:DYN
TEMPLIM
(K:BACKBUF)
(K:UNAVBG)

Selection
Keyword Function
IOEX General I/o Driver.
JOBACCT Background Job Account-
ing (includes CLOCK1).
DEBUG For'egrovnd/background
.program
debugging.
HEXDUMP Hexadecimal patches.
Memory dumps.
RAD dumps.
I/O table dumps.
COC Chqracter-oriented com-
mun ications handler (in-
e! ud'es RC OC).
DISMISS Task dismissal on "wait"
I/O.
ERRORLOG Error logging on disk file
[,entries] (includes ERRORSUM)
entries defaults to
K:BLOCK/S.
ANALYSIS Saves system status
and
memory snapshot on disk
or magnetic tape in
event of critical system
error.
R:IDxx Includes
RBM module xx
as a resident rather than
nonresident module.
Size
200
100
625
40 or 115t
1000-1100
130
240+4 * I/o
channels +s *
entries
K:BLOCK S
180
15
128,256 16
or 512
325 +2 * devices
+ 3 * I/o
channels
{See Table 5}
RSVPTABL
~entries]
Specifies other than de- 3 * entries
fault Reserve Peripheral
function. Entries specifies
maximum number of con-
current Reserve requests
(active +queued). If en-
tries is specified as zero,
the Reserve Peripheral
function is not included
in the system (default is
5
entries).
RESIDENT I/O TABLES AND ROUTINES
The size of the resident area allocated for I/o tables and de-
vice specific routines depends on the specific peripheral de-
vices selected. The basic size (in words} of the I/o table is
8 x number of I/O channels
15 x number of device types
+ 22 x number
of disk File Control Table entries
(disk DFNs)
+ 2 x number
of operational labels
t1l5 if only RAD and no disk in system.
Add to this amount
the values given in Table 4 if the
corresponding device type is included in the system (SYSGEN
parameter DEVICE FILE INFO).
Since SYSGEN attempts to store whatever optional tables it
can into unused interrupt locations, the size of the unused
interrupt region cangenerally be subtracted from this ac-
cumulated sum. The size of the unused area can be deter-
mined by subtracting the value specified for the SYSGEN
parameter MAX. INT. LOC from 399. However, this fig-
ure wi II be somewhat larger than the true size since not all
of these unused interrupt locations can be used for tables.
FILE CONTROL TABLE ALLOCATION
The Fi Ie Control Table (FCT) is indexed by device-file num-
ber and contains information about all devi ce-fi les in the
system. The total size of the File Control Table is deter-
mined and allocated at SYSGEN time. The device-fi Ie
numbers (DFNs) are assigned on the basis of the order in
which devices are defined. For example, since the first
device defined must always be a keyboard/printer, DFN 1
will always specify a keyboard/printer. Devices other than
disk have permanent device-fi Ie number assignments made
at SYSGEN time. SYSGEN allows room for up to 50 per-
manent device-fi les (not including disk fi les).
A separate device-fi Ie number (i. e., FCT entry) is re-
quired for each open disk fi Ie. Hence, the total number
of entries necessary in the Fi Ie Control Table for all disk
fi les is the maximum number of simultaneously open fi les.
At SYSGEN
time, the user must specify this maximum num-
ber of disk files for his foreground programs. To this value,
SYSGEN wi II add the nU'mber of foreground devi ce-fi les
required for operation of RBM. This number is 2, plus 1
if the checkpoint area is included, plus 1 if job accounting
is included, plus 1 if a 7242/46 disk pack is included, plus 1
if
error logging is included. For the background, nine
device-fi les wi" be allocated (a sufficient number for the
system processors), plus the number of background DFNs
requested by
the user.
OPERATIONAL LABEL ASSIGNMENTS
During SYSGEN the user specifies the selected standard
operational labels for background and foreground, and
assigns each to a device-fi Ie number (other than a disk
fi Ie number) or to zero. These assignments wi II be main-
tained as default assignments for the selected operational
label. (Assignment to zero is essentially a Inull l assign-
ment, but does produce an entry in the appropriate table
for the specified operational label.)
After all inputs are made by the user, SYSGEN allocates
two to six additional reserve entries in the Foreground Op-
erational Label Table for disk file labels, and nine additional
reserve entries in the Background Operational Label Table.
A total of 100 operational labels can be allocated and as-
signed at SYSGEN time, including those automatically
allocated by SYSGEN.
Resident I/o Tables and Routines 13

Table 4. I/o Table and Routine Increments by Device Type
Device Increment
~ze (Decimal)
Type Model Number First Input
Additional
Inputs
Line Printer
(LP)
J45T--------J4l>O-
------
j-----
3461
7440
25
16
3463 744]
3464 7445
3465 7446
7450 40 15
Keyboard/Printer (KP)
4191
I
4193
38
23
7012
32
16
8091
Paper Tape (PT) 7020
43
16
7060
Card Reader (CR) 7120
7121
41 12
7122
7140
Card Punch (CP) 7160 164
135
--
7165 41
12
Magnetic Tape (MT) 3325 7323
3335 7332
155
13
7315 7333
7316 7362
7322 7372
Graph Plotter
(PL)
7530
26
12
7531
Special device for
M:IOEX use
'XX'
7 7
3203
3204
3231
161
40
3232
3233
RAD Disk (RD)
7202
7203
11
11
7204
7232
7251
111
20
7252
--_._---
7242
361
11
7246
14 Resident I/O Tables and Routines