COM3310 Glossary Flashcards
2PC
Two-phase commit - Commit and roll back - first check goes to all Resource Managers and checks whether everything is ok to commit, then decides whether to commit or not (2 phases) (if even one Resource Manager cannot go ahead, then the whole thing does not go ahead)- the idea that a transaction can be of multiple parts and that the system needs to either commit everything or roll back on everything if there is a failure
ACID
Requirements of a transaction system: Atomicity, Consistency, Isolation, Durability Atomic: Meaning either all changes are made at once or not at all Consistency: Database remains consistent according to the rules defines such as referential integrity both before and after the transaction is executed Isolation: Requires that transactions are executed as if not other transactions are executed (e.g. hidden) Durability: When a transaction is stated as complete, the updates to the database are preserved irrespective of any system failures
Address Space
The complete range of addresses available to a program. An address space contains user data, system data and programs, some of which are common to all address spaces.
ADRDSSU
Application-level Utility - Primary disk dump and disk restore program provided with z/OS
Alias
An alias is a special entry in the master catalog, pointing to a user catalog, that coincides with the high level qualifier of a data set name.
AMS
Access Method Services: A utility to define and delete VSAM structures, such as files and indexes
AORs
Application-Owning Regions - In a CICSPlex configuration, a CICS region devoted to running applications
Application Designers & Programmer
Design, build, test and deliver mainframe applications
Atomic Instant
The instant when the coordinator records the fact that it is going to tell all the resource managers to either commit or roll back
Batch Processing
The running of jobs on the mainframe without user interaction - reads and processes data in bulk and produces output
BMS
Basic Mapping Support - 3270: Sends a menu to the terminal, in between command prompt and interface I think
CA
Continuous Availability
CBU
Capacity BackUp - Temporary upgrade for customers who have a requirement for a robust disaster recovery solution, creates backup systems that is not paid for unless a disaster is activated (special contract with IBM)
CEC
Central Electionic Complex (like CPC (Central Processing Complex) - the physical collection of hardware that includes main storage, one or more central processors, timers and channels (main system))
CEDA
CICS Command - Used for creating and managing resource definitions (Conversational)
CEMT
CICS Command - Master Terminal Commands (INQUIRE - Set File, SET - Disable a program, ) (Conversational)
CF
Coupling Facility
CHPID
Channel Path Identifier: The channels are all integrated in the main processor box
CICS
Customer Information Control System - General purpose transaction subsystem for z/OS
CICS Explorer
A system management tool that offers a simple, integrated and intuitive way to manage one or more IBM CICS systems
CICS TS
CICS Transaction Server: Often called simply CICS, is a powerful, mixed-language application server that runs on the IBM mainframe operating system called z/OS. Commonly divided into three regions (TOR, FOR and AOR)
CICSPlex
CICS Architechture - CICS is divided into several regions and each region can play a different role. Each region has its own VSAM file detailing the resources that are used exclusively for that region
CIU
Customer Initiated Upgrade - Web-based solutions for customers ordering and installing upgrades via the IBM Resource Link
Cluster
z/OS Parallel Sysplex or z/VM Single System Image (SSI) cluster
CMS
Conversational Monitor System - Operating system shipped with z/VM - A virtual machine only operating system, supporting a personal productivity environment, development and installing and maintaining z/VM - Has its own file systems - Runs many applications, compilers etc.
CO
Continuous Operations
COMMAREA
Pg 423 - CICS - Standard way for CICS prgrams to communicate with each other - The name of the area containing the data to be passed or the area to which results are to be returned (also an option to invoke CICS programs)
Conversational
A program that conducts a conversation with the user - Program waits for users response
CP
Control Program / Central Processor: The part of the computer that contrains the sequencing and processing facilities for instruction execution, initial program load, and other machine operations.
CPACF
CP Assist for Cryptographic function
CPC
Central Processor Complex - The physical collection of hardware that includes main storage, one or more central processors, timers and channels
CSGM
CICS Command - CICS Good Morning - Command to bring up the welcome screen
CSTOR
Memory / Central Storage / Main Storage
DASD
Direct Access Storage Device (Disks)
Datasets
A collection of logically related data records, such as a library of macros, medical records or a source program.
DB2
Shared I/O - DB2 is a database software from IBM. It is a Relational Database Management System (RDBMS). DB2 is designed to store, analyze and retrieve the data efficiently. DB2 product is extended with the support of Object-Oriented features and non-relational structures with XML. Tables are formatted in a typical logical structure composed of rows and columns
DB2 Buffer Pools
A buffer pool is an area of main memory that has been allocated by the database manager for the purpose of caching table and index data as it is read from disk. Every DB2® database must have a buffer pool. Each new database has a default buffer pool defined, called IBMDEFAULTBP.
DB2 Catalogue
The DB2 catalog consists of tables of data about everything defined to the DB2 system, including table spaces, indexes, tables, copies of table spaces and indexes, and storage groups.
DB2 Com: ALTER
Change the storage size
DB2 Com: BIND
DB2 Bind compiles all your sql statements into an executable format.
DB2 Com: COMPILE?
Dynamic SQL?
DB2 Com: COPY/RECOVER
It is vital that a DBA takes image copies of the data and the indexes with the COPY utility to recover data. The RECOVER utility can recover back to an image copy for a point-in-time recovery
DB2 Com: DCLGEN
Allows you to automatically generate your source definitions for the DB2 objects that will be used in your program
DB2 Com: DISPLAY
Displays status for whatever suffix you add after
DB2 Com: LOAD/UNLOAD
After the tables are created, the DBA uses the LOAD utility to populate them, with the ability to compress large amounts of data. UNLOAD allows the DBA to move or copy data from one subsystem to another
DB2 Com: PRECOMPILE?
Because compiled cannot handle SQL, the precompile step comments out the SQL statements and leaves behind a CALL statement to DB2.
DB2 Com: REORG
Reorders data in sequence
DB2 Com: RUN
When you execute your application program, the load module is loaded into main storage.
DB2 Com: RUNSTATS
Gathers statistics for use by the optimiser
DB2 Data Sharing
The ability of concurrent subsystems (such as DB2 or IMS DB) or application programs to directly access and change the same data, while maintaining data integrity
DBA
Database Administrator: Guides and approves database design, controls access to integrity and availability, providing standards, approving the use of any programs that access them, determines rules and security for access - not responsible for the data
DBMS
Database Management System
DFH
The 3 character optional software component identifier for CICS
DFMSMS - dfp
Core piece of DFSMS that deals with reading and writing
DFSMS
Data Facility Storage Management Subsystem - Performs the essential data, storage, program, and device management functions of the system. Used to automate storage management for data sets (rules based: the manager of the SMS can set rules of exactly what should be backed up, when it should be moved to ‘secondary storage’ (archived) depending on something like user priority e.g. high priority customer may get better backed up data than a low priority stakeholder) (dfp, dss, rmm, hsm, OPT)
DIMM
Dual In-Line Memory Module - Holds array of chips for RAM
DMA
Direct Memory Access
DR
Disaster Recovery
Dynamic SQL
Refers to SQL statements that are only partially or totally unknown when the program is written. Only when the program runs does DB2 know what the statements are and is able to determine the appropriate access paths.
EAL5
Highest level of security ceritification. The IBM mainframes are the world’s only servers to achieve this certification.
ESCON
Like FICON (fibre connection)
ESS
Enterprise Storage System: Allows multiple I/Os to execure concurrently against the same disk device without queuing. This functionality allows a device to contain more than one access path using a base address along with aliases.
Extensibility
Taking future growth into consideration
FICON
Fibre Connection architecture - Fibre channel protocol used for connectivity to traditional mainframe disk and tape
FORs
File-Owning Regions - In a CICSPlex configuration, a CICS region devoted to files
GDPS
Geographically Dispersed Parallel Sysplex - Ultimate disaster recovery and continuious availability
HA
High Availability
HBA
Host Bus Adapter - FICON Express
HFS
Hierarchical File System: A mountable file system, which is being phased out by zFS
Hipersockets
Technology that provides high-speed TCP/IP connectivity within a central processor complex. It eliminates the need for any physical cabling or external networking connection between servers running in different LPARs
HLQ
High level qualifier: Possible high level qualifiers are your userid or jobname
HMC
Hardwar Management Console: A user interface through which data centre personnel configure, control, monitor and manage IBM System Z hardware and software resources.
HSA
Hardware Save Area - Not addressable by the user, special component of the mainframe central storage area loaded at power on
Hypervisor
The hypervisor drives the concept of virtualization by allowing the physical host machine to operate multiple virtual machines as guests to help maximize the effective use of computing resources such as memory, network bandwidth and CPU cycles.
I/O
Input/Output: To describe any program, operation or device that transfers data to or from a computer to or from a peripheral device
I/O Channels
I/O Channels are part of the Channel Subsystem (CSS). They provide connectivity for data exchange between servers (and external contol units, devices or networks.
I/O Devices
e.g. a hard drive
ICFs
Integrated Coupling Facility: A large memory scratch pad used by multiple systems to coordinate work by sharing resources between LPARs or used for workload balancing when configured for a Parallel Sysplex
ICKDSF
System-oriented Utility - Used primarily to intialise disk volumes
IDCAMS
Utility program primarliy used to create and manipulate VSAM data sets
IEBCOPY
Utility program that copies members from one Partitioned Dataset to another as well as compress a Partitioned Dataset
IEBDG
Utility Program - Used to create records in which fields can be generated with various types of data. IEBDG is typically used to create test data.
IEBFBR14
Utility Program - The only function of this sprogram is to provide a zero (0) completion code.
IEBGENER
Utility program that copies one sequential data set to another
IEBUPDATE
Utility Program - Used to create multiple members in a partitioned data set, or to update records within a member
IEHINITT
System-oriented Utility - Used to write standard labels on tapes
IEHLIST
System-oriented Utility - Used to list a parititoned data set directory or a disk volume table of contents (VTOC)
IFB
InfiniBand: Is used as the pervasive, low-latency, and high-bandwidth interconnect that has low processing impact and is ideal for carrying multiple traffic types
IFL
Integrated Facility for Linux - Processor used exclusively by Linux
INSTALL (Within CICS)
Within CICS - deploy a group of resources to a single action
IOCDS
I/O Control Data set - Translates physical I/O addresses into device numbers that are used by the operating system software to access devices
IPL
Inital Program Load
ISPF
Interactive System Productivity Facility: The menu-driven interface for TSO/E This collection of menus and panels offers a wide range of funtions to assist users in working with data files on the system
JCL
Job Control Language - used to control job scheduling and execution
JES2
Job Entry System 2: Reads jobs into the system, converts them into readable form, processes etc.
KVM
Kernel-based Virtual Machine (open source Linux Hypervisor) - been ported to z Systems and can be run in an LPAR to host Linux guests - Does not provise the same robustness, security, integrity and manageability features at hypervisor level of z/VM
LCSSs
Logical Channel Subsystems: The largest machine today can support up to four LCSSs, each having a maximum of 256 channels
LP
Logical Partition
LPAR
Mainframe Logical Partitioning - represents an operating system instance, independent & its own operating system (equivilant of a seperate mainframe for most practical purposes) Resources and devices can be shared across several LPARs (eg. Channels, OSA Express Ports, FICON Express Ports)
Mainframe
A mainframe is what businesses use to host the commercial databases, transaction servers, and applications that require a greater degree of security and availability than is commonly found on smaller-scale machines.
Master Catalog
The Master Catalog usually stores only the name of the user catalogs. A z/OS system always has at least one master catalog.
MCS Console
A console that is used to enter commands and receive messages
Middleware
Software ‘layer’ between the operating system and the user or user application e.g. database management systems
Minidisk
z/VM disk partitioning technology
MIPS
Processor that runs more efficiently due to restricted commands
MRO
Multi-Region Opertation: Enables the seperation of different CICS functions into different CICS regions (address spaces)
NIC
Network Interface Card
Normalisation
1NF: Structure of a table - not a set of data in one field (e.g. Phone: 07908617522; 07463927103, need to be split) 2NF: 1-to-1 - If each column that is not in the key provides a face that depends on the entire key Above are the main two. 3NF: 1-to-many relationships - If each non-key column is independent of the other columns and depends only on the key 4NF/5NF: many-to-many relationships - If no rows contain two or more independent multivalued facts about an entity
OLTP
Online Transaction Processing
OOCoD
On/Off Capacity on Demand
OSA
Open Systems Adapter: Modern way to connect consoles, interface for networking (like ethernet)
Parallel Sysplex
Clustering technologies that allow the customer to operate multiple copies of the operating system as a single system - Network connects to sysplex (of individual computers) which each connect to a shared data system. Can scale nearly linearly from 2 to 32 systems. Parallel Sysplex technology allows multiple mainframes to act as one. It is a clustering technology that can provide near-continuous availability.
PAVs
Parallel Access Volumes: Allows multiple I/Os to execure concurrently against the same disk device without queuing. This functionality allows a device to contain more than one access path using a base address along with aliases.
PCT
Program Control Table: A CICS transaction is given a 4-character name, which is defined in the PCT
PDS
Partitioned Dataset: A z/OS library containing members, such as source programs
PDS/E
Partitioned Dataset Extended: Have a different internal format, which gives them increased usability. In a PDS, you store programs as load modules, in a PDSE you store programs as program objects. Improved user productivity and system performance - PDSE automatically reuses space within the data set without the need for anyone to periodically run a utility to reorganise it.
PLPA
Pageable Link Pack Area
Production Control Analyst
Person who ensures that batch workloads run to completion without error or delay
Pseudo-Conversational
A series of non-conversational transactions that appear to the user as a conversation - Program only runs when the user invokes action e.g. POST on a webpage (Frees up resources compared to conversational)
PU
Processing Units within a Central Processor Complex (can be referred to as a CP - single processor)
QDIO
Queued Direct I/O
RAIM
Redundant Array of Independent Memory
RAS
Reliability, Availability and Serviceability. When something “exhibits RAS characteristics”, its design places a high priority on the system remaining in service at all times. Reliability: Self-checking and self-recovering capabilities. Availability: The system can recover from a failed component without impacting the rest of the running system. The highest levels of availability are obtained with DB2 and the Parallel Sysplex on the System z architechture. Serviceability: The system can determine why a failure occured.
RDBMS
Relational Database Management System
RDF
Record Descriptor Field - Occopy the last 7 bytes of the Control Interval - displays record length information and the number of records it applies to
Referential Integrity
Relationships between tables established by defining foreign keys
Region
Address Space
RHEL
Red Hat Enterprise Linux
RM
Resource Manager - Subsystem which manages the resources in the back-end inolved in a transaction (examples include WAS, CICS, IMS & DB2)
RMF
Application-level Utility - Resource Management Facility used to measure various aspects of system performance
RoCE
Remote DMA over Converged Ethernet (card) - RoCE Express
RRS
Resource Recover Services - Primary sync point coordinator
S/360
The first general purpose (scientific and commercial) computer (mainframe) introduced in 1964
SAPs
System Assist Processor - Used for the I/O subsystem - each machine has at least one
SC
System Controller - Processor?
SCH
System Control Hub
SDSF
System Display and Search: Used to review the output for successful completion or review and correct JCL errors. SDSF allows you to display printer output held in the JES spool area. Additionally can view the system log and monitor jobs as they’re being processed
SE
Support Element: A hardware unit that provides communications, monitoring and diagnostic functions to a central processor complex (CPC)
SE (Architechture)
Shared Everything architechture - “Shared Everything” is a complete multi-tenant architecture where all the tenants data is stored in the same database, on the same hardware and separated logically using metadata. This allows all the infrastructure costs to scale evenly.
SIE
Start Interpretive Executation Instruction - (like the LPAR hypervisor) uses the SIE instruction to “run” virtual processors for a given virtual machine - No performance penalty for running z/VM in an LPAR - No shadow page tables required for DAT-on guests
SLES
SUSE Linux Enterprise Server
SMC-D
Shared Memory Communications - Direct Memory Access - Hipersockets
SMS
System Managed Storage / Storage Management Subsystem: A facility used to automate and centralise the management of storage. Using SMS, a storage administrator describes data allocation characteristics, performance and availability goals, backup and retention requirements, and storage requirements to the system through data class, storage class, management class, storage group, and ACS routine definitions.
SPUFI
SQL Processor Using File Input: It allows you to write and save one or more SQL statements at a time
SSI
Single System Image: Even though a system may have a Parallel Sysplex, the collection of systems within the Sysplex should appear as a single entity to the operator. A single system image brings reduced complexity from both operational and definition purposes.
Static SQL
Refers to complete SQL statements that are written in the source code. Letting the database know in advance what the SQL statement is and then posting the variable later on.
STP
Server Time Protocol - Unified time between a cluster (Based on NTP)
SUPERZAP
System-oriented Utlility - Can be used to patch disk records
Syncpoint Coordinator/Manager or ‘Initiator’ or RRS
The system that makes decisions - speaks to all systems (PREPARE command), each system will reply as to whether they are ready to complete the task or not, then the syncpoint manager will begin phase 2 as to whether it will commit (if unanimous) or rollback
System Administrator
Person who maintains the critical business data that resides on the mainframe
System Operator
Person who monitors and controls the operation of the mainframe hardware and software
System Programmer
Person who installs, customizes and maintains the operating system
System Z Business Class
Intended for small to midrange enterprise computing. Entry point providing for a maximum of 10 configurable Processing Units (PU).
TCP/IP Service
Tranmission control protocol/internet protocol: A hardware independent communication protocol used between physically seperated computers. It was designed to facilitate communication between computers located on different physical networks. The general term used to describe the suite of protocols that form the basis of the internet.
TDISK
On-the-fly disk allocation pool
TOR
Terminal Owning Region - A CICS region devoted to managing the terminal network
TS
Temporary Storage
TSO/E
Time Sharing Option/Extensions: Users log on to the z/OS system through TSO/E (User interface for z/OS in relation to it’s menu-driven interface ISPF) Solely, it provides users with a single-user logon and a basic command prompt
Typical roles in IT for mainframe:
- System Programmer: Person who installs, customizes and maintains the operating system - System Administrator: Person who maintains the critical business data that resides on the mainframe - Application Designers & Programmers - System Operator: Person who monitors and controls the operation of the mainframe hardware and software - Production Control Analyst: Person who ensures that batch workloads run to completion without error or delay
Typical vendor roles:
- Hardware Support - Customer Engineer - Software Support - Field Technical Sales Support - Systems Engineer - Client Representative
U
Units (slot within a mainframe rack), standard rack = 42U high
UCB
Unit Control Block - Small piece of virtual storage describing the characteristics of a device to the operating system (contains device address and tracking progress of I/O e.g. ‘Device Busy’)
UOW
Unit Of Work - A transaction
UR
Unit of Recovery: In transaction systems, commit and roll back referes to the set of actions used to ensure that an application program either makes all the changes or not to the resource represented by a single Unit of Recovery
User Catalog
Data set used to locate the DASD volume in which the requested data set is stored.
VIO
Virtual I/O
VSAM
Virtual Storage Access Method - Provides more complex functions than other disk access methods (Record format: KSDS, ESDS, RRDS, LDS)
VSAM - ESDS
Entry Sequence Data Set: This form of VSAM keeps records in sequential order. Records can be accessed sequentially.
VSAM - KSDS
Key Sequence Data Set: This is the most common use for VSAM. Each record has one or more key fields and a record can be retrieved (or inserted) by key value. This provides random access to data. Records are of variable length. So that the system can retrieve an item without searching all preceding items in the data set. Ideal for data items that are used frequently and in an unpredictable order.
VSAM - LDS
Linear Data Set: This is, in effect, a byte-stream data set and is the only form of a byte-stream data set in traditional z/OS files (as opposted to z/OS UNIX files). A number of z/OS system functions use this format heavily, but it is rarely used by application programs.
VSAM - RRDS
Relative Record Data Set: This form of VSAM allows retrieval of records by number: record 1, record 2, and so on. This provides random access and assumes the application program has a way to derive the desired record numbers
VTOC
Volume Table of Contents: Manages the storage and placement of datasets, a VTOC lists the data sets that reside on its volume, along with information about the location and size of each data set, and other data set attributes.
WLM
Workload Manager - Unified Workload Management - The component of z/OS that manages the processing of workloads in the system according to the company’s business goals (SLAs - Service Level Agreements) - Optimises the assignment of resources to the users that have greater priority
Z Systems
IBM Z is a family name used by IBM for all of its mainframe computers from the Z900 on
z/Architecture
z/Architecture is IBM’s 64-bit instruction set architecture implemented by its mainframe computers.
z/OS
A widely used mainframe operating system, designed to offer a stable, secure, continuously available and scalable environment for applications running on the mainframe.
z/OS Images
An image within a sysplex
z/TPF
z/Transaction Processing Facility - Special purpose system used by companies with high transaction volume such as credit card companies
z/VM
z/Virtual Machine - Has two basic components: a Control Program and a Single-User Operating System. Hypervisor (runs other operating systems in the virtual machines it creates e.g. z/OS, Linuk, z/VSE and z/TPF can run as guest systems)
z/VSE
z/Virtual Storage Extended - Smaller, less complex base for batch and transaction processing, excellent for running routine production workloads consisting of multiple batch jobs. Popular for smaller mainframe computers.
zAAPs
z Systems Application Assist processor (taken over by ZIIP, don’t need to know)
Zeus
Provides free remote access to z/OS, z/VM and Linux for Universities
zFS
System z File System: A file system that stores files in VSAM linear data sets
zHyperLink
Provides low latency direct connection between Z14 and an IBM Disk Subsystem (DS8880)
zIIPs
z/OS Integrated Information Processor: A specialised processor that provides computing capacity for selected data and transaction processing workloads, and for selected network encryption workloads
Zystem Z Enterprise Class
Intended for large businesses. Larger frame than Business Class offering up to 64 configurable Central Processors.
