| |
Abbreviation |
Term |
Description |
| A |
APPC |
Advanced Program to Program Communication |
Protocol for program to program
communication between multiple systems |
|
ASCB |
Address Space Control Block |
z/OS control block which
represents a virtual storage entity tight to an end user or set of programs
to execute |
| B |
BCP |
Basic Control Program |
z/OS or MVS kernel routines |
| C |
CCW |
Channel Command Word |
Command to exchange I/O between
z/OS and storage devices |
|
CDS |
Couple Dataset |
Dataset which contains control
information to setup a parallel sysplex environment |
|
CEC |
Central Electronic Complex |
The system (processors, memory,
I/O adapters), not including I/O devices |
|
CFCC |
Coupling Facility Control Code |
Operting System of the coupling
facility |
|
CICS |
Customer Information Control Server |
A transaction monitor that runs
primarily on z/OS |
|
CKD |
Count Key Data |
System z data architecture |
|
CP |
Central Processor |
Standard processor of a System z |
|
CP |
Control Program |
Main component of z/VM |
|
CPU |
Central Processing Unit |
see CP |
| D |
DAE |
Data Analysis and Elimination |
z/OS RAS function which ensures
that only data is captured which is needed to analyse system problems |
|
DASD |
Direct Access Storage Device |
A storage device which supports
direct access (typically a disk) |
|
DB2 |
Database |
Relational database based on E.
F. Codd's theory of relational databases |
|
DDF |
Distributed Data Facility |
Component of DB2 to exchange
information with external clients |
|
DEDB |
Data Entry Database |
Fast path database for IMS |
|
DL/I |
Data Language Interface |
Database of IMS |
|
DRDA |
Distributed Relational Database Architecture |
Distrubuted database
architecture of the open group standard |
| E |
ECKD |
Extended Count Key Data |
see CKD |
|
ESA/390 |
Enterprise Systems Architecture/390 |
32-bit predecessor of System z
architecture |
|
ESCON |
Enterprise System Connection |
Half-duplex optical fiber serial
channel |
|
ESPIE |
Extended Specify Program Interruption Exit |
Interrupt exit routine |
|
ESTAE |
Extended Specified Task Abnormal Exit |
Recovery routine for z/OS user
or problem state programs |
|
ETR |
External Time Reference |
Device to synchronize all TOD
(time-of-day) clocks in a cluster environment (Parallel Sysplex) |
|
EXCP |
Execute Channel Program |
z/OS macro to execute an i/o
operation |
| F |
FCP |
Fibre Channel Protocol |
Transport protocol for
transporting SCSI commands on Fibre Channel networks |
|
FICON |
Fibre Channel Connection |
Full-duplex fibre optical serial
channel |
|
FIFO |
First In, First Out |
Queuing mechanism |
|
FLIH |
First Level Interrupt Handler |
Intterupt handler which gets
immediatly control when the interrupt occurs |
|
FRR |
Functional Recovery Routine |
Recovery routine for z/OS system
programs |
| G |
GDPS |
Global Dispersed Parallel Sysplex |
Parallel Sysplex which is
spatially distributed to ensure high availability |
|
GRS |
Global Resource Serialization |
z/OS subsystem which supports
global lock management |
| H |
HCA |
Host Communication Adapter |
Infiniband I/O Adapter |
|
HCD |
Hardware Configuration Dialog |
z/OS component to define I/O
devices to the system |
|
HFS |
Hirarchical File System |
UNIX file system on z/OS |
| I |
ICF |
Integrated Coupling Facility |
Processor on system z which
allows to run coupling facility control code |
|
IFL |
Integrated Facility for Linux |
Processor on system z which
allows to execute z/VM and Linux operating systems |
|
IML |
Initial Microcode Load |
Process to enable System z
hardware to execute virtual systems |
|
IMS |
Information Management System |
A transaction monitor and
database for z/OS (introduced 1968 for the Apollo space program) |
|
IODF |
I/O Definition File |
Data file which contains the I/O
definitions for System z (created by HCD) |
|
IPC |
Inter Process Communication |
Protocol for system processes to
interact which each other |
|
IPL |
Initial Program Load |
Process to start the z/OS
operating system |
|
IRB |
Interrupt Request Block |
z/OS Control Structure to start
an I/O routine |
|
IRD |
Intelligent Resource Director |
A combination of multiple z
technologies to enhance the autonomic capabilities of PR/SM, z/OS and the I/O
subsystem |
|
IRLM |
IBM Resource Lock Manager |
Lock manager for DB2 and IMS |
|
ISPF |
Interactive System Productivity Facility |
End user interface for TSO users |
| J |
JES |
Job Entry System |
z/OS subsystems which support
the execution of scheduled programs |
| L |
LCP |
Logical Processor |
Representation of a processor to
the virtual system or logical partition |
|
LPAR |
Logical Partition |
Container which hosts an
operating system to execute on System z Virtualization layer |
| M |
MMU |
Memory Management Unit |
Hardware component which handles
virtual memory |
|
MPL |
Multi Programming Level |
Term which expresses the ability
of workload to access system resources |
|
MSU |
Million of Service Units per Hour |
Unit to measure CPU capacity on
System z |
|
MTTW |
Mean Time To Wait |
Algorithm which gives access to
units of work based on their deliberate wait time |
|
MVS |
Multiple Virtual Storage |
Origanl name of z/OS based on
the ability to support multiple virtual storage guests |
| O |
OLTP |
Online Transaction Processing |
Umbrella term for transaction
processing |
|
OSA |
Open System Adapter |
|
| P |
PAV |
Parallel Access Volume |
Protocol which supports parallel
access to the same I/O device |
|
PCP |
Physical Processor |
see CP |
|
PPRC |
Peer to Peer Remote Copy |
A protocol to replicate a
storage volume to a remote site |
|
PR/SM |
Process Resource and System Manager |
Management component of the
logical partition technology of System z |
|
PSW |
Program Status Word |
Central register to control all
program execution |
| Q |
QDIO |
Queued Direct I/O |
memory to Memory I/O mechanism
between LPARs on System z |
| R |
RACF |
Resource Access Control Facility |
z/OS subsystem which supports
access control |
|
RAS |
Reliability, Availability, Serviceability |
Terminology to depict the
robustness of information technology systems (originated from IBM mainframe) |
|
REXX |
Restructured Extended Executor |
Interpretive Execution Language
from IBM |
|
RLS |
Record Level Sharing |
VSAM access method which
introduces record sharing and serialization |
|
RMF |
Resource Measurement Facility |
z/OS Performance Monitor |
|
RRMS |
Resource Recovery Management Services |
z/OS component to synchronize
the activities of various syncpoint managers |
| S |
S/360 |
IBM System/360 |
Is a mainframe computer system
family announced by IBM on April 7, 1964. It is the computer architecture of
which System z is the current incarnation. |
|
SAP |
System Assist Processor |
System z I/O processor |
|
SDWA |
System Diagnostic Work Area |
Control structure to capture
information in case of an abnormal program termination |
|
SE |
Support Element |
Laptop that acts as user
interface to System z machine |
|
SIE |
Start Interpretive Execution |
|
|
SIGA |
Signal Adapter |
|
|
SIGP |
Signal Processor |
Instruction to inform a
processor about status change |
|
SLIH |
Second Level Interrupt Handler |
Term which encompasses a set of
specialized interrupt handling routines |
|
SMF |
Systems Management Facility |
z/OS component which supports
performance and status logging |
|
SMP |
Symmetric Multiprocessing |
A computer system with all
physical processors accessing the same storage and I/O subsystems |
|
SRB |
Service Request Block |
Control structure to execute a
z/OS system program |
|
SRM |
System Resource Manager |
Component of z/OS for resource
management (introduced 1974, now part of WLM) |
|
STP |
Server Time Protocol |
Follow-on to ETR |
|
SU/sec |
Service Unit per second |
Capability of a System z
processor to execute instructions |
|
SVC |
Supervisor Call |
Interface to invoke a z/OS
system program |
|
Sysplex |
System Complex |
A single logical system running
on one or more physical systems |
|
System z |
IBM mainframe computer brand |
Current 64-bit incarnation of
the S/360 architecture |
|
System z10 BC |
System z10 Business Class |
Mid-range model of current
System z10 processor family |
|
System z10 EC |
System z10 Enterprise Class |
High end model of current System
z10 processor family |
| T |
TCB |
Task Request Block |
Control Structure to execute
user or problem state programs on z/OS |
|
TSO |
Time Sharing Option |
z/OS component which supports
the parallel execution of multiple end users on MVS |
| U |
UCB |
Unit Control Block |
z/OS control structure which
represents an I/O device |
|
UoW |
Unit of Work |
An execution unit on z/OS |
|
USS |
Unix System Services |
z/OS component which supports a
full functioning UNIX environment on z/OS |
| V |
VCPU |
Virtual CPU |
|
|
VMM |
Virtual Machine Monitor |
Hypervisor or control program to
run multiple virtual machines |
|
VSAM |
Virtual Storage Access Method |
A set of access methods for
System z I/O devices |
|
VTAM |
Virtual Terminal Access Method |
Access methode for
communications devices (now part of z/OS TCPIP subsystem) |
|
VTOC |
Volume Table of Content |
Index of a DASD device |
| W |
WLM |
Workload Manager |
Central z/OS component for
resource management (introduced 1995) |
| X |
XCF |
Cross System Coupling Services |
z/OS Services which support the
exploitation of a z/OS sysplex |
|
XES |
Cross System Extended Services |
z/OS services which support the
access to the coupling facility |
|
XRC |
Extended Remote Copy |
System z protocol for data
replication |
| Z |
zAAP |
System z Application assist Processor |
System z processor to execute
Java code. This processor type can only be used by z/OS and only for
instrumented software like the Java Virtual Machine. A special instruction
tells the dispatcher when Java execute starts and ends. |
|
zFS |
System z File System |
UNIX file system on z/OS |
|
zIIP |
System z Integrated Information Processor |
System z processor to execute
code which is subject to get offloaded from regular processors. The offload
capability is described by the middleware through an interface to WLM and the
z/OS dispatcher. Exploiters are middleware like DB2 and TCPIP. |