1. Chapter 1: The new mainframe
Special Edition
Smarter …
… systems
… software
… storage
… services
Redbook Copy

2. Chapter 1 objectives
After completing this chapter, you will be able to:
List ways in which the mainframes of today challenge the traditional thinking about
centralized computing versus distributed computing.
Explain how businesses make use of mainframe processing power, the
typical uses of mainframes, and how mainframe computing differs from
other types of computing.
Outline the major types of workloads for which mainframes are best suited.
Name five jobs or responsibilities that are related
to mainframe computing.
Identify four mainframe operating systems.
Describe how IBM zEnterprise System is used
to address IT problems.

3. Key terms in this chapter
application programmer
architecture
batch processing
compatibility
e-Business
EBCDIC
high availability
infrastructure
mainframe
online processing
platform
production control
punched card
RAS
scalability
server farm
system administrator
system operator
system programmer
transaction processing

4. 7th April 1964, Poughkeepsie NY
A new generation of electronic computing equipment was introduced today by International Business Machines Corporation. IBM Board Chairman Thomas J. Watson Jr. called the event the most important product announcement in the company's history.
The new equipment is known as the IBM System/360.
"System/360 represents a sharp departure from concepts of the past in designing and building computers. It is the product of an international effort in IBM's laboratories and plants and is the first time IBM has redesigned the basic internal architecture of its computers in a decade. The result will be more computer productivity at lower cost than ever before. This is the beginning of a new generation - - not only of computers - - but of their application in business, science and government."
System/360 offered a choice of five processors and 19 combinations of power, speed and memory. A user could operate the same magnetic tape and disk products as another user with a processor 100 times more powerful.
System/360 also offered dramatic performance gains, thanks to Solid Logic Technology - half-inch ceramic modules containing circuitry far denser, faster and more reliable than earlier transistors.
System/360 monthly rentals will range from $2,700 for a basic configuration to $115,000 for a typical large multisystem configuration.
Comparable purchase prices range from $133,000 to $5,500,000.
Prices as low as $3,000,000 per MIP !
In 1964 a nice house cost about $6,000
Today zSeries pricing is less than $1000 per MIP

5. The Mainframe Charter – Providing a Strategic Framework
It is our intention to…
Innovation
Provide leadership in innovation to enhance the use of the IBM mainframe to support increasingly integrated and flexible business processes for the On Demand Business.*
Value
Enhance the value proposition and lower the cost of computing of mainframe solutions in a way that is compelling, clear, and consistent.*
Community
Support programs designed to foster vitality in the IBM mainframe community, helping to promote a strong application portfolio and world-class support services.*
* Excerpted from the Mainframe Charter – August 2003

6. z/OS Innovation – Redefining the mainframe for 5 decades!
HW S/ S/ S/370XA – 31 bits ESA/390
CMOS –
Parallel Sysplex
zEnterprise
and zBX SW
MVT, PCP
MFT
VSE
MVS – VTAM MVS/XA z/OS
VM z/VM
z/VSE
MVS/ESA
OS/390
VSE/ESA
Unix System Services
TCP/IP
Appliances
Optimizers
IMS CICS DB Linux
WebSphere
zAAP zIIP EAV
z/Architecture – 64 bits
z/OSMF
ServerPac,
Unicode
Java XML
This innovation from z/OS comes from a long history of continuing to redefine the mainframe. z/OS itself is the evolution of the original mainframe operating system: OS/360. From the introduction of OS/360 in 1964, through the 64-bit z/Architecture in 2000, customer applications have been protected along with the dramatic delivery of new function.
z/OS has evolved over these years with a strong interrelationship with mainframe servers and middleware. This close tie results in the quality of service that only the zSeries mainframe platform can offer.
Model z zBX

7. Mainframes in our midst
Are prevalent, yet hidden from public eye
Not often publicized – stable, reliable, dependable.
Contrast with other forms of computing, such as PCs.
Present opportunities for college graduates in a variety of technical fields.
Exploits hybrid computing capabilities for centralized
business requirements
Despite the predominance of mainframes in the business world, these machines are
largely invisible to the general public, the academic community, and indeed many
experienced IT professionals. Instead, other forms of computing attract more attention, at
least in terms of visibility and public awareness. That this is so is perhaps not surprising.
After all, who among us needs direct access to a mainframe? And, if we did, where
would we find one to access? In truth, we are all mainframe users, whether we realize it
or not.

8. What is a mainframe?
A mainframe is a computing system that 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.
The power of a mainframe provides computing speed and capacity, enabling it to perform high volumes of processing.
The mainframe can process a mixed workload of jobs from different time zones and of different types concurrently.
The mainframe offers optional appliances to offload workload to optimize throughput and cost savings.
Today, computer manufacturers don’t always use the
term mainframe to refer to mainframes. Instead, most have taken to calling any
commercial-use computer—large or small—a server, with the mainframe simply being
the largest type of server in use today. IBM, for example, now refers to its mainframes as
zSeries servers. We use the term mainframe in this textbook to refer to computers that
can support dozens of applications and input/output devices to simultaneously serve
thousands of users.
The presence of a mainframe often implies a centralized form of computing, rather than a
distributed form of computing. Having data centralized in a single mainframe repository
saves customers from having to manage updates to more than one copy of their business
data, and increases the likelihood that the data is current.
Model z zBX

9. Mainframe Attributes:
Compatibility with System z operating systems, applications, and data.
Centralized control of resources.
Hardware and operating systems that can share access to disk drives with other systems, with automatic locking and protection against destructive simultaneous use of disk data.
A style of operation, often involving dedicated operations staff who use detailed operations procedure books and highly organized procedures for backups, recovery, training, and disaster recovery at an alternative location.
Hardware and operating systems that routinely work
with hundreds or thousands of simultaneous I/O operations.
Hybrid workload computing
Model z zBX

10. Mainframe facts Who uses mainframes?
Most Fortune 1000 companies use a mainframe environment
60% of all data available on the Internet is stored on mainframe computers
Why mainframes?
Large-scale transaction processing
Thousands of transactions per second
Support thousands of users and application programs
Simultaneously accessing resources
Terabytes of information in databases
Large-bandwidth communications
Model z zBX

11. Who uses mainframe computers?
Businesses today rely on the mainframe to:
Perform large-scale transaction processing (thousands of transactions per second)
Support thousands of users and application programs concurrently accessing
numerous resources
Z196: Each PU chip
has up to four cores
running at 5.2 GHz,
which means a 0.19
ns cycle time.
Business Class (BC) Enterprise Class (EC)

12. Factors contributing to mainframe use
The reasons for mainframe use are many, but most generally fall into one or
more of the following categories:
Reliability, availability, and serviceability (RAS)
Security
Scalability
Continuing compatibility
Evolving architecture
Extensibility
Total cost of ownership
Environment friendly
Reliability The system’s hardware components have extensive
self-checking and self-recovery capabilities. The system’s
software reliability is a result of extensive testing and the ability to
make quick updates for detected problems.
One of the operating system’s feature is a Health Checker that
identifies potential problems before they impact availability or, in
worst cases, cause system or application outages.
Availability The system can recover from a failed component without
impacting the rest of the running system. This applies to
hardware recovery (the automatic replacing of failed elements
with spares) and software recovery (the layers of error recovery
that are provided by the operating system). The highest levels of
availability are obtained with DB2 and the Parallel Sysplex on the
System z architecture.
Serviceability The system can determine why a failure occurred. This allows for
the replacement of hardware and software elements while
impacting as little of the operational system as possible. This
term also implies well-defined units of replacement, either
hardware or software.
A computer system is available when its applications are available. An available
system is one that is reliable, that is, it rarely requires downtime for upgrades or
repairs. And, if the system is brought down by an error condition, it must be
serviceable, that is, easy to fix within a relatively short period of time.
Mean time between failure (MTBF) refers to the availability of a computer
system. The new mainframe and its associated software have evolved to the
point that customers often experience months or even years of system
availability between system downtimes. Moreover, when the system is
unavailable because of an unplanned failure or a scheduled upgrade, this period
is typically short. The remarkable availability of the system in processing the
organization’s mission-critical applications is vital in today’s 24x7 global
economy. Along with the hardware, mainframe operating systems exhibit RAS
through such features as storage protection and a controlled maintenance
process.
System z servers are among the most secure servers on the market, with mean
time between failures (MTBF) measured in decades. In fact, the System z is
designed for up to % availability with Parallel Sysplex clustering. The
System z is designed to provide superior qualities of service to help support high
volume, transaction-driven applications, and other critical processes. It supplies
tremendous power and throughput for information-intensive computing
requirements.
Beyond RAS, a state-of-the-art mainframe system might be said to provide high
availability and fault tolerance. Redundant hardware components in critical
paths, enhanced storage protection, a controlled maintenance process, and
system software designed for unlimited availability all help to ensure a
consistent, highly available environment for business applications in the event
that a system component fails. Such an approach allows the system designer to
minimize the risk of having a single point of failure (SPOF) undermine the overall
RAS of a computer system.
Enterprises many times require an on demand operating environment that
provides responsiveness, resilience, and a variable cost structure to provide
maximum business benefits. The mainframe’s Capacity on Demand (CoD)
solutions offer permanent or temporary increases in processor capacity and
additional memory. This robust serviceability allows for on going upgrades during
concurrent workload execution.
Model z zBX

13. Typical mainframe workloads
While batch processing is possible on distributed systems, it is not as commonplace as it is on mainframes because distributed systems often lack:
Sufficient data storage
Available processor capacity, or cycles
Sysplex-wide management of system resources and job scheduling

14. While batch processing is possible on distributed systems, it is not as commonplace as it is on mainframes because distributed systems often lack:
Sufficient data storage
Available processor capacity, or cycles
Sysplex-wide management of system resources and job scheduling
Strong I/O subsystem
Batch processes typically have the following characteristics:
Large amounts of input data are processed and stored (perhaps terabytes or more),
large numbers of records are accessed, and a large volume of output is produced.
Immediate response time is usually not a requirement. However, batch jobs
often must complete within a “batch window,” a period of less-intensive online
activity, as prescribed by a service level agreement (SLA).
Information is generated about large numbers of users or data entities
(for example, customer orders or a retailer’s stock on hand).
A scheduled batch process can consist of the execution of hundreds or
thousands of jobs in a pre-established sequence.

15. Typical batch use
1. At night, numerous batch jobs running programs and utilities are processed.
These jobs consolidate the results of the online transactions that take place
during the day.
2. The batch jobs generate reports of business statistics.
3. Backups of critical files and databases are made before and after
the batch window.
4. Reports with business statistics are sent to a specific area for
analysis the next day.
5. Reports with exceptions are sent to the branch offices.
6. Monthly account balance reports are generated and sent to all bank
customers.
7. Reports with processing summaries are sent to the partner credit card
company.
8. A credit card transaction report is received from the partner company.
9. In the production control department, the operations area is monitoring
the messages on the system console and the execution of the jobs.
10.Jobs and transactions are reading or updating the database (the same
one that is used by online transactions) and many files are written to tape.
Attention: Today’s mainframe can run standard batch processing such as COBOL as well as UNIX and Java programs. These runtimes can execute either as standalone or participate collaboratively within a single jobstream. This makes batch processing extremely flexible integrating different execution environments centrally on a single server.

16. Online transactions are familiar to most people -
Examples include:
ATM machine transactions such as deposits, withdrawals, inquiries, and transfers
Supermarket payments with debit or credit cards
Purchase of merchandise over the Internet
For example, inside a bank branch office or on the Internet, customers are using online services when checking an account
balance or directing fund balances.
In fact, an online system performs many of the same functions as an operating system:
Managing and dispatching tasks
Controlling user access authority to system resources
Managing the use of memory
Managing and controlling simultaneous access to data files
Providing device independence
How might the end users in these industries interact with their mainframe systems?
Multiple factors can influence the design of a company’s transaction processing system, including:
Number of users interacting with the system at any one time.
Number of transactions per second (TPS).
Availability requirements of the application.
For example, must the application be available 24 hours a day, seven days a week, or can it be brought down briefly
one night each week?

17. Online transactions usually have the following characteristics:
A small amount of input data, a few stored records accessed and processed, and a small
amount of data as output
Immediate response time, usually less than one second
Large numbers of users involved in large numbers of transactions
Round-the-clock availability of the transactional interface to the user
Assurance of security for transactions and user data
Logging and journaling for backup and recovery

18. Typical online use 1. A customer uses an ATM, which presents
a user-friendly interface for various functions:
withdrawal, query account balance, deposit, transfer,
or cash advance from a credit card account.
2. Elsewhere in the same private network, a bank
employee in a branch office performs operations,
such as consulting, working with fund applications,
and money ordering.
3. At the bank’s central office, business analysts tune
transactions for improved performance. Other staff
use specialized online systems for office automation
to perform customer relationship management, budget
planning, and stock control.
4. All requests are directed to the mainframe computer for processing.
5. Programs running on the mainframe computer perform updates
and inquiries to the database management system (for example, DB2).
6. Specialized disk storage systems store the database files.

19. Speciality engines to characterize workload
z/OS LPAR
WAS Application
zAAP
TCP/IP
HiperSockets
z/OS LPAR
All of the IBM System z specialty engines can operate on the same machine together
DRDA
DB2
WAS
Application
Application
Application
not on System z D R A
TCP/IP
Star
Schema
zAAP CP
zIIP
DRDA
TCP/IP
HiperSockets
Linux on System z LPAR
Application
ICF
IFL

20. The zIIP and the zAAP The zIIP is a chip that's really hip.
The MIP on a zIIP is not charged full clip.
The zIIP (like the zAAP) will benefit the app.
The zIIP and the zAAP will make pricing a snap.
by Dr. zEUSS

21. System z Concurrent Upgrade – Customer Controlled
On/Off Capacity on Demand - Temporary upgrade
Non-disruptive temporary addition of CPs, IFLs, ICFs zAAPs and zIIPs
Upgrades requiring parts (e.g., for a z9 EC Model S08 to S18 upgrade) not supported
"Right to use" feature - Orderable as MES or with new build to initiate contract and administrative setup
Customer orders and installs upgrade via Resource Link and IBM RSF
Non-disruptive removal when capacity is no longer wanted
Break even point is 90 days
CIU – Customer Initiated Upgrade - Express - Permanent upgrade
Customer capability to order and install permanent upgrade
Not included
Upgrades requiring parts (e.g., for a z9 EC Model S08 to S18 upgrade)
Channel upgrades by LIC enable of existing ports
CIU feature - MES ordered to initiate contract and administrative setup
CBU – Capacity BackUp - Temporary emergency capacity upgrade
Non-disruptive temporary addition of CPs, IFL, ICF, zAAPs, zIIPs in an emergency situation
CBU contract required to order CBU features and CBU LIC CC
Customer activates upgrade for test or temporary emergency
Concurrent downgrade after test or recovery completed
Note: Upgrades are non-disruptive only where there is sufficient hardware resource available and provided pre-planning has been done

23. Mainframe Operating System Heritage
OS/360 -> OS/VS -> MVS/SP -> MVS/XA -> MVS/ESA -> OS/390 -> z/OS z/OS is IBM’s premier zSeries operating system, is a highly secure, scalable, high-performance enterprise operating system on which to build and deploy traditional and Java-enabled applications, providing a comprehensive and diverse application execution environment.
DOS/360 -> DOS/VS -> VSE/SP -> VSE/ESA -> z/VSE VSE enables proven, robust, and cost-effective solutions. VSE provides sturdy batch and industrial strength on-line transaction processing (CICS) capabilities. VSE can fit comfortably into a legacy of thrifty, dependable VSE solutions.
ACP -> TPF-> z/TPF
TPF is the platform driving the business-critical systems for many of IBM's largest and most sophisticated users of online transaction processing - airlines, railroads, hotels, financial services, government, credit card and banking industries.
CP/67 -> VM/370 -> VM/SP -> VM/XA -> VM/ESA -> z/VM z/VM provides a highly flexible test and production environment for enterprises deploying the latest e-business solutions. z/VM helps enterprises meet their growing demands for multi-user server solutions with support for a broad range of operating systems.
There is one other OS that is not on this chart, Linux. It is life to this platform (application growth, skills issues, MIPS growth). All the problems the MF has had Linux has been a God Send! It’s the survive and thrive. It’s thriving now and there is one reason why – Linux!

24. Introducing the IBM zEnterprise System
For the first time it is possible to deploy an integrated hardware platform that brings
mainframe and distributed technologies together, producing a system that can start
to replace individual islands of computing and that can work to reduce complexity,
improve security, and bring applications closer to the data they need.
ENSEMBLE – A collection of one or more zEnterprise nodes (including any attached zBX) that are managed as a single logical virtualized system by the Unified Resource Manager, through the use of a Hardware Management
Console (HMC).
Model z zBX
xHyp = Hypervisor for System x
pHyp = Hypervisor for System p
PR/SM = Processor Resource Systems Manager
SE = Support Element
AMM = Advance Management Module
ISS = Integrated Support Services
DP = Data Power
HPC = High Performance Computing
DWA = Data Warehouse Acceleration

25. zEnterprise Value Proposition
Networking
Workloads
Workloads
Networking
Workloads
Workloads
Networking
zE can reduce customer costs via two key value propositions. Fit for purpose choice can reduce run time acquisition costs compared to an all blades strategy. Consolidation on a single platform together with structured management practices can also achieve significant reductions in labor cost.
These charts tell the fit for purpose side of the story.
Fit for Purpose minimizes cost of acquisition and preserves quality of service
Centralized platform and structured practices minimize labor costs 25

26. Summary The New Mainframe:
Plays a central role in the daily operations of the world’s largest organizations – and the daily lives of most people.
Is known for its reliability, security, and enormous processing capabilities.
Is designed for processing large scale workloads and serving thousands of
users and transactions concurrently.
Is managed by highly skilled technical support staff.
Runs a variety of operating systems.
Can execute hybrid and complex transaction types.
Model z zBX

27. 1.13 Questions for review
To help test your understanding of the material in this chapter, perform the following tasks:
1. List ways in which the mainframe of today challenges the traditional thinking about centralized computing versus distributed
computing.
2. Explain how businesses make use of mainframe processing power, and how mainframe computing differs from other types of
3. List some of the factors that contribute to mainframe use.
4. List three strengths of mainframe computing, and outline the major types of workloads for which mainframes are best suited.
5. Name five jobs or responsibilities that are related to mainframe computing.
6. This chapter mentioned at least five operating systems that are used on the mainframe.
Choose three of them and describe the main characteristics of each one.

28. 1.14 Topics for further discussion
Here are topics for further discussion:
1. What is a mainframe today? How did the term arise? Is it still appropriate?
2. Why is it important to maintain system compatibility for older applications?
Why not simply change existing application programming interfaces whenever improved interfaces become available?
3. Describe how running a mainframe can be cost effective, given the large number of roles needed to run a mainframe system.
4. What characteristics, good or bad, exist in a mainframe processing environment because of the roles that are present in
a mainframe shop?
(Efficiency? Reliability? Scalability?)
5. Describe some similarities and differences between application development for mainframe systems compared to other
systems.
6. Most mainframe shops have implemented rigorous systems management, security, and operational procedures. Have
these same procedures been implemented in distributed system environments? Why or why not?
7. Can you find examples of mainframe use in your everyday experiences?
Describe them and the extent to which mainframe processing is apparent to users. Examples might include the following:
a. Popular websites that rely on mainframe technology as the back-end server to support online transactions and databases.
b. Multitiered applications that interface with mainframe resources.
c. Mainframes used in your locality. These might include banks and financial centers, major retailers, transportation hubs,
and the health and medical industries.
8. Can you find examples of distributed systems in everyday use? Could any of these systems be improved through the
addition of a mainframe? How?
9. How is today’s mainframe environment-friendly?
Discuss with examples.