Mainframes in IT environments

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7 Νοε 2013 (πριν από 4 χρόνια και 3 μέρες)

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End of Study Thesis


Mainframe
s in IT

environments

www.supinfo.com

L
ast
N
ame
: Salsmann

First Name:

Flavien

Campus Booster ID
:
28622






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A
bstract


This end of study thesis focuses on the Mainframe computer systems. Not very known, thes
e

platforms are often victims of many prejudices

which

veracity must be

verified
.
Are they depreca
ted?
Are they still used? Are they doomed to disappear? Will they be replaced by distributed GNU/Linux
server?
What are and will be their state? To answer these questions
, we will study the position of
Mainframes
in enterprises, as well as their legitimacy

in big infrastructures. To better understand
their
importance, we will present several aspects of this platform, theoretical as well as technical.


First, after having defined the context of this thesis, we'll study the current position of Mainframes in
t
he world, especially in companies. We'll try to understand what they really are and to have a new
look on them. We
’ll

then briefly present their evolution and study why they are still used despite
criticisms that are often made about their age. We’ll ident
ify factors of their continued existence,
such as the need to capitalize on
the
existing

structure
, notably in banks.


Therefore, we'll see that billions of dollar
s

as been invested in
them
and that most important
consulting group
such
as Gartner still be
lieve in

them
. Then, we will
present
an overview of
their
qualities not present on distributed servers, or not enough efficient for big infrastructures. After
having study its overall strength, its place in IT environments will be presented, as well as
its

market.


In a second step, we will present technologies used under these environments, their efficiency and
their legitimacy in a modern world. We will add system commands to theoretical concepts in order to
concrete their presentation. If possible, we wi
ll compare existing technologies under conventional
systems as Linux with Mainframe technologies, in order to see if they are really obsolete or modern.


Obviously, we will present the hardware used by these machines, as well as their IBM proprietary
oper
ating system called z/OS.
As

basic concepts such as file system are very
different

compared
to
tho
se
that
customers are often used to
use
on other OS, we will briefly explain their specifi
cities,
advantages and defects.
Several
products

will then be descri
bed, in order to better apprehend most
subtleties of this platform, as security and workload management. Then, we'll see how it deal
s

with
needs
as
disaster recovery and virtualization

thanks to
technologies
like
Parallel Sysplex and z/VM.


Finally, we wil
l attempt to define the future of Mainframes. To do so, we will present the role they
can have in server consolidation projects. Then, we will describe why it could be interesting in
Data
Center
s, notably for its TCO, and according to the new emerging prob
lems, such as
energy

and place
costs. New applications scheduled on this
platform

will also be presented, such as Gameframe for
online gaming, and the recent zSolaris contract validated with Sun. At last, we will project the broad
market trends, and the po
sition Mainframes could occupy in few years. We’ll try to define if they can
be attractive to a wider range of businesses, and get out of their “niche” market status.






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Acknowled
gement


First, I’d like to thank
all

IBMer
s

I met during my
internship
,
especi
ally

Mr Alain Richard
,
Mr Fre
deric
Rondeau
, Bruno Paganel and Eric Gaillard

for their patience,
advices and
many courses.
They spent a
lot of time

each day to answer
all
my questions,
teach

me a lot of concepts,
and
give

me
invaluable

feedback
s from their
experience in
Mainframe

environments
.
I’ve really been impress
ed
by their IT
culture.

It’s been a real pleasure to work with them
.

And I would even say an
honour
.

I thank ESI SUPINFO and IBM
for organizing
the IBM zNextGen training. Thanks to it, I realize
d that I
lacked many skills that could be interesting to acquire.

It has changed my professional aspirations.

I’d also like to thank all the persons who read my thesis
and gave me their impression,
incomprehension, and
then
helped me to improve it.

I would

like to thank my friends, who supported me during my studying

at SUPINFO
,
and who made
these years unforgettable, especially Lo
uis Champion,
Nathalie Rufin,
Guillaume Sudrie,
Florent
Chambon, Brice Dekany, Rémi Vincent, Philippe Job, Jérome Masse, Laurent

Bodin, Mickeal Desbois,
Rémi Assailly
, Selim Meskine, Gilles Dallemagne

and Gaëtan Poupeney
.

Finally, I would like to thank my parents
and my sister
who helped me to join SUPINFO and for all the
support and love they gave me.

This document would surely n
ot have been written without them.





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Table of Content


Abstract

................................
................................
................................
................................
...........................

2

Acknowledgement

................................
................................
................................
................................
...........

3

Table of Content

................................
................................
................................
................................
..............

4

Introduction

................................
................................
................................
................................
.....................

6

1/ Mainframe Computers: Myths and Realities

................................
................................
................................

7

1.1

What’s all about these old dinosaurs?

................................
................................
................................
..........

8

1.2 Who is
enough mad to use it?

................................
................................
................................
......................

9

1.3 Why are they still running?

................................
................................
................................
...........................

9

1.4 What is its place in IT environments?

................................
................................
................................
.........

19

1.5 The Mainframe market nowadays… As dead as itself?

................................
................................
..............

21

2/ Mainframe Today: Denver the Last Dinosaur?

................................
................................
...........................

23

2.1 An impressive advanced Hardware

................................
................................
................................
............

23

2.2

Specialty Engines

................................
................................
................................
................................
........

27

2.3

z/OS : the IBM Operating System

................................
................................
................................
...............

35

2.4 An horrible user interface

................................
................................
................................
...........................

36

2.5 z/OS file system

................................
................................
................................
................................
..........

40

2.6 JCLs for batch processing

................................
................................
................................
............................

46

2.7 Jobs, performances, and network management

................................
................................
........................

49

2.8

Transaction Servers and Database: Middleware

................................
................................
........................

52

2.9 RACF Security Server

................................
................................
................................
................................
...

54

2.10 DFSMS: Managing Data

................................
................................
................................
............................

61

2.11

Health Checker: Auditing system

................................
................................
................................
..............

68

2.12
Virtualizati
on technologies

................................
................................
................................
.......................

71

2.13 Solutions for high and continuous availability

................................
................................
..........................

78







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3/ Mainframe in the future: Dead or Messiah?

................................
................................
..............................

85

3.1 Server Consolidation

................................
................................
................................
................................
...

85

3.2 An interesting total cost

of ownership

................................
................................
................................
.......

92

3.3 A mature and credible platform

................................
................................
................................
...............

106

3.4 Emerging applications

................................
................................
................................
...............................

108

3.5 SWOT and future market

................................
................................
................................
..........................

110

Conclusion

................................
................................
................................
................................
....................

111

References

................................
................................
................................
................................
...................

112






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Introduction


Nowadays, the
IT
market seem
s

to be divided into two sectors,
composed of either Linux or
Microsoft Windo
ws

platforms
. The
advent of distributed servers during the 90’s has

amplified this
simple representation
. However, other solutions
were

used
before the rise of the personal computer.
Indeed, between the 60’s and the 80’s most companies primarily used huge
computers called
“Mainframes”. Most popular were IBM models, from OS/360 to the AS/400.
Every modern
infrastructure had a Mainframe, and it was used for most application, such as bank transactions. As a
result, most critical programs were written during th
at period, most of time in COBOL

language
.

As these
critical

applications are perfectly working and
needed
many

investments from companies,
they

are still running

today

on Mainframes.
Most of them are then

still executed for historical
reasons

and are must

have for many companies
.

Yet
, these
systems are ignored

or even

unknown
by
general public

and
by
most IT Specialist
. They are often judged as old machines doomed to
disappear, and
are
compared to "dinosaurs"
, because they execute very old programs
. Many p
eople
tend to say
Mainframe
s

have become totally obsolete and no longer meet
the modern market

criteria, and
thus
will be irreversibly replaced by distributed servers
defined as “modern”.

However,
major infrastructure
continue to use it, and not only becau
se it can help
them
to capitalize
on

the
ir

existing. Indeed,
Mainframes are systems implemented in big companies to meet
very
specific
needs
.

They propose very advanced technologies helping enterprises to better
define
their
Business Recovery Plan, such as

Parallel Sysplex for continuous and high availability, or Copy Services
for high level data replication.
Therefore, they
constitute an essential component of IT environments.

In recent years, Mainframes greatly evolved, notably through the System z9 range

from IBM, having
impressive hardware capabilities and offering uptime of about 99,999%.

More and more
IT managers

find Mainframe to be
the only system able to
effectively
support very large workloads, such as in
banks

for transactions
,
and to meet their p
erformance, security and reliability needs.

As v
irtualization technologies are more and more used to execute several
instances

of Linux systems,
with
solutions such as Xe
n
Source
which are very popular in companies, the Mainframe alternative
could be serio
usly considered in many infrastructures. Indeed,
Mainframes benefit from more than
thirty year of experience in the virtualization domain,
and could have a major place

in server
consolidation projects. It could then conquer a new market, usually reserved f
or x86 platforms.

In the next year, the
Data Center

crisis will explode, because of considerations that were not
suitably

taken into account, such as energy and place costs du to massive use of distributed servers.

The
Mainframe could be
effective to solve

these problems
, as its TCO is not so high, despite prejudices.







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1
/
Mainframe

Computers:

M
yths
and
R
ealities


Mainframe

Computers

are
often
seen

as old and
archaic
systems.
When
one
talk

to
ave
rage people
about “
Mainframe
s


and
ask them to
think about

these machines
,
they will probably
ask
you if
you’re talking about
these
huge
“things”
which
need so much place

that a

small
room is not enough.

Well,
maybe that
’s

a caricature
… B
ut
give

it a try a
nd you’ll see

by yourself
!

I
f only there were living
during the
60’s
they
would be
probably
true.

Mainframe
s

were indeed systems hosted in huge room
-
sized metal box, needed an incredible
amount of electricity,
space and air
-
conditioning
.

It needed about
th
ousand square

meters
, up to
3000
to take
place.

But this time is over. It’s now like a big refrigerator
, nothing more, taking the
place of about two frames
containing
standard x86 server
s
.

Mainframe

evolved
.

This is all about this

thesis
.



Lot of people
will also tell you
Mainframe

Computers are dead, and
that
the small one
s

still
being
used will be replaced by
grid computing

technologies…

Well…
I
n fact,
the truth is
while

people’s mind
didn’t evolve about
Mainframe

Computers technologies,
these last one
did.

Another
reality
is that e
ven if
it’s
been
said
they we
re finished
,
the
y
’re
still
used
.

People don

t really
have
a
concrete idea about what a
Mainframe

really is, even in
most
IT Environment
s
.

It thus remains important to
precise what
are

Mainframe
s
,
w
hich companies
are
using them,
their
real place in the
world
and why
they’
re
still
there, despite
violent
criticisms and
jokes.





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1
.1

W
hat’s all about
the
s
e

old
dinosaur
s
?


First of all, it seems important to precise that our modern world couldn’t be what i
t is without
Mainframe
s
.
Although
Mainframe

technologies

are
referred as a legacy platform which is no longer
strategic for companies
, they play an essential and central role in all usual operations people does
each days. Whatever you do, if you deal with
some kind of data, then you’ll pass through a
Mainframe

for sure. Most of Fortune
5
00 companies own one or more
!

Bank
s
, finance, insurance, health care, government, each transaction of big infrastructures is treated
by
Mainframe
. It really is the heart of
all great
Data Center
s. It’s the only system which can handle so
much data with
such speed

and reliability.

The situation is very paradoxica
l,
indeed,
these machi
nes are seeing as old and creepy
,
but in reality
they’
re the most technologically

advanced
.
He
re is a definition
I found
quite
ironic and
relevant
.


An obsolete device still used by thousands of obsolete companies serving billions of obsolete
customers and making huge
obsolete

profits for their obsolete shareholders.


The Devil’s IT Dictionnary

Be
hind all these concepts
and passionate debates, what
really is a
Mainframe
?

Well,
the most
important point
is it’s a machine which has been
designed since
its
beginning to achieve all its
customers’ workloads in time.

It automates thousand of actions in or
der to
reach
consistent business
objectives.

This is the only system we expect to NOT
stop,
crash
or

fail.

It

requires unmatched qualities, such as
security, availability and integrity.

Supporting
hundred of
thousands

I/O operations
due

to
numbers
of
simul
taneous transactions

which can be
potentially vital for
initiators,
it just have to be sure.

In
people mind,
a machine crash is a “normal” thing, it can happen anytime for any reasons, you just
have to reboot it, and that’s it.
A
Mainframe

execute
s

so much

critical applications it cannot
crash.

Fai
l, crash or
slow
-
down

is NOT an option

Then, a
Mainframe

is
a device
which can serve
at the same time
thousands of users without any
errors.

Customers
who

use
Mainframe

expect them to have
24/24 up
-
time
, as the
y

can’t allow a
minute
of down
-
time, since
it means
millions of dollars lost.

Since its own reputation is concerned,
customers want the best machine to host their most hot applications.
That’s what
Mainframe
s

do.
They’re

just reliable

machines
,

w
hat are not
others on
the
market
, nothing less
.


A
Mainframe

is a

computer system designed to continuously run very large, mixed

workloads at high levels of utilization meeting user defined service level objectives.”

IBM





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1
.2

Who
is enough mad
to
use
it?


Even if
Mai
nframe

computers dominate the landscape of large
-
scale business, they remain obsolete
for much people, and as it was said before, being considered as “dinosaurs”, since emerging
technologies leap into the public eye such as cool 3D effects, great look and
feels… All that stuff.

Then
w
ho make them still live?

Well…

To be
honest
, as
you maybe should have
guessed

it
, everyone use

Mainframe

at least once in
his life.

This is
obvious
.

You used
a
Mainframe

computer at one point or another.

Let’s take an easy
exam
ple. Got an American Express or a Blue Card? Then you’ve used a
Mainframe

to interact with
your bank account. This is also the same process when you use ATM (Automated Teller Machine).

In fact,
world’s

economy
rests on
Mainframe

Computers. Then, people ju
st can’t forget about it and
says it’s dead, it would be totally wrong. This is, was, and continue to be the foundation of business.

Just
t
hink about
it:

there are more transactions

daily

executed on
Mainframe

than web pages server!

Most member
s

from Fortu
na 500 are running a
Mainframe
.

Every big project
involves

a
Mainframe

in

some part.

Only big enterprises are aware of there existence and more precisely of their advantages.


1
.3

Why
are

they
still

running
?


Companies still use
Mainframe
s

for a numbers of

reaso
ns which people are not enough interest
ed

in.




Capitalize on existing IT
infrastructure

You have to understand
Mainframe
s

are

the base of every
big IT infrastructure. When
big society
raised

these last years, the only way to provide
them a correct wa
y to
deal with their
data

was
nothing but
to
use
Mainframe
s
.

IBM machines were the only one able to do it.

Then, every large
batch jobs

dealing with
big services such as
general ledger and payroll processing

were running on
these infrastructures.
A lot of
money

has been

spent
for these applications which are base
s

of
many
modern
structure
s
.


Applications hosted on
Mainframe

systems represent a
n

invest
ment

a
bout 1500 billions of dollars
.”

Gartner Group

Every critical
application
, which are
currently
running

in structures such as bank were
written

in

COBOL
.

They’ve been tested, fixed and run perfectly.

Even if they
’ve

thirty years old, they
work.

Customers don’t want to lose their passed
investments, and they know it will be less expensive to
reuse or adapt e
xisting applications
than rewrite them again in
a “cool and hype” new language.

They don’t care about
it;

they just want their program do run correctly.

Furthermore, t
his is more
careful

to
use something which as been validated, it reduce
s

risks related to

new developments.





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More than 200 billions of COBOL code
lines are

still
used

and 5 more are added each
year
.”

Gartner Group

Companies

also
know that
i
f they launch a huge project under
Mainframe

environment;

it will still
work in

many years
. Contrary
to
other platform
s

such as Windows or UNIX/Linux,
IBM
wants its
platform to hold
its entire

legacy.

It means that
customers
are able
to launch
their oldest applications
on the latest
z/OS and System z.

Let’s have a try with another system, such as Windows, or

even
Linux.
Take an old application
from Windows 3.1
and make it run on your

new Windows Vista
..
.
If it
works

without doing anything but trying to
make it
run
, you’re lucky.

With
Mainframe
s
, customers
know they have
continuing compatibility, there capital

is preserved.

This compatibility
across
decades of changes and enhancements is the
Mainframe
’s
hardware and
software
designer’s

top priority
.

That’s why JCL
s

are still used in order
to
preserve compatibility with
older
tasks
so that they can continue to
b
e executed
without
any
modification
s
.


The ability of our

system both to

run software

requiring new

hardware

instructions

and to run

o
lder
software

requiring the

original

hardware

instructions

is
extremely important

for our customers
.


IBM

IBM
Mainframe
s

make possible to
re
use
all
applications
customers

invested

in
.

That’s a
huge
point,
because
big
enterprises
really
live thanks to their “old”
and
legacy

applications.



Huge Workloads

Mainframe
s

benefit from comfortable and huge hardware to process very sign
ificant workload.
As a
result, a single system can
scale up to process a billion transactions

per
day
, and up to 13 billions for
a clustered

System z9
, which represents more than the amount of transaction in a week for the New
York Stock Exchange!

Mainfram
e
s

support different kinds of workloads,
which can be
defined in two categories, “basic”
batch processing (often old applications running during nights, to make statistics and
long job
s
), and
online transaction processing, which are the most used during da
ys.



Batches processing

don’t need any user interaction. They’re often planned to be executed
night
ly
, when all machine power is available
. They have to advantages to be able to process
huge data, such a as terabytes to create valuable statistics.

Banks us
e them to produce important reports about their customers.
You can see it as
C
ron
defined in an UNIX
C
ron tab
, but with advantages with often lacks it distrusted servers
environments, such as a huge available processors capacity and significant data storag
e do
deal with.

These jobs do not need an immed
iate response but have to be complete in what
we called a “batch window”,
which in
the
maximum
period it can be running.





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Online processing

occurs interactively with users.

Unlike batches processing, they have
to be
executed very
fast
, and response time is the most
important thing
with
,

of course
,

data
integrity
.
As
these transactions often depend

of the enterprise core functions, each of them
is critical and has to be
treated

with attention. When you take money

in an ATM machine
,
you want it to be fast.
Every user who use
s

the same transaction at the same time want
s

the
same thing.
Them, they have to be treated in fraction of seconds.

Immediate response
is
needed, which suppose
s

high performance, integrity, and
data protection.

Numbers of industry use
Mainframe

to be as fast as possible: banks with, ATM, travel
enterprise with online ticket checking reservation, government to process tax processing,
etc…
If
customers
use a distributed server infrastructure,
time

needed to meet
their
needs,
especially integrity, will need much
important
. Indeed,
even if
they can effectively

process
the

job, their I/O capacity cannot be compared with a
Mainframe
. As the
whole
system is
run
ning

on the same hardware,
data check
and p
rocessing
is far more speed.

Mainframe

systems
also use advanced technologies
hardware and software, to improve huge
workloads processing.
As a result, IBM
designed its machine as “balanced systems”. It means it
balances
server’s

components to processor, m
emory and I/O scalability.
It’s then
able to deal
with
large quantities

of data available to support transactions.
In the Operating System, a manager called
WLM (
Work

Load

Manager)

allocate resources
when and where needed, offering dynamic resource
priorit
ization.
Then, WLM
decides

the resources level to be applied to meet a particular service goal,
in a particular
part of the system
for example.

Workload
Manager monitors the system and
continuously
re
adapts processing to meet
needs
, and
then systems can ru
n at 100% utilization.

For really big infrastructure, EWLM (Enterprise WLM) allow

you to automatically monitor distributed and heterogeneous or homogeneous workloads across an
IT infrastructure to better achieve defined business goals for end
-
user services
.

Please note that a
s Linux can be executed under
Mainframe

environment thanks to z/VM,
workloads
can be balanced and allocated as if you were under a distributed
server infrastructure

for some kind
of needs

(Apache Web servers responding to numbers of htt
p requests for example)
. It also benefits
from all feature
s

due to the System Z partition system, as HiperSocket for data exchange between
each

virtual

operating

system
. Data flow then operates
at
memory speed.

In other words, in this
situation,
a
Mainfram
e

can be a
n improved x86
cluster
.



Reliability, Availability and
S
erviceability

The
se

three concepts are also
known as “RAS”.
RAS is

one of the most important
things

when you
talk about

a system or an infrastructure, as it includes
numbers of aspects
of a c
omputer and
application
,
revealing its
capacity to
be in service every time.

In fact, we can
define a system
in
seconds knowing its RAS level.

The more
an infrastructure
RAS
level is
high,

the more
it may be
trusted.
We
can
then
talk about
a
24/24
and
7/7

service
, which mean there is no down
-
time

accepted
,
and
we
expect

IT infrastructure
s

with RAS
characteristics

to have
a full up
-
time.

These feature
s

help
a system
to stay fully operational
for a very long period (months and even years

for
Mainframe
s
)

with
out reboot or crash.





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The IBM
Mainframe

platform retains industry
-
leading availability characteristics even

for single
-
system instances. For example, standard service availability commitments

from tier one service
providers in commercial
Data Center

outso
urcing agreements

suggest that the
Mainframe

is
delivering 99.9% to 99.99
9
% scheduled availability

versus 99.5% for distributed server

platforms in non
-
clustered configurations.

Forrester

It seems important to define
precisely each terms of RAS.

As you ma
y
notice,
these are
hardware

and
software
attributes,
which
may
be
founded in distributed environment systems

but which
truly are
prized

by
Mainframe

users.

Here is the definition of each characteristic.



Reliability
:
Ability to
avoid
faults
, if founded, th
ey’re very quickly fixed



Availability
:
Deals with the up
-
time, which means the amount of time a machine will
be
running
and being fully operational
, even if a problems occurs.
For
example
, a system
with
continuous
availability would stop a process causing
problem and will go on without
having
to launch oth
er
services

after fail
.



Serviceability
: Ability
of the system to diagnose

itself
.

It can then detect faults before they
happen and fix them.

It
avoids

significant human
intervention
and downtime caused by
maintenance.


RAS works as if each of its part was some kind of layer, used by hardware and software.








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To illustrate that concept, l
et’
s take
a very simple
example:

a CPU
fails



C
ustomers should be aware
that
Mainframe

technologies are very advanced t
o support all these
features.

For example, there are no SPOF (Single Point of Failure) in a
Mainframe
, every
hardware

component is
redundant: CPs, memory,
I/O

channel
, etc…

You can even change
hardware without

having to stop the system.
It’s been designed
to handle this kind of operations.


Errors detections are also
used
every time:

each instructions sent to CPs are mirrored, and then
double
-
checked. If this comparison does not provide the same results,
the
CP is known as unreliable
and a spare is then

use
d to execute its workloads.

It a fantastic feature to assure integrity of every data processing.

Other
technologies are used to
ensure data safety
, integrity

and backup
,
as RAID
(
Redundant Array of Independent Drives
)
and
cyclic

redundancy check checksums.

At last but no least,
very
modern
technologies such as
Parallel Sysplex
enable

scalable runtime
execution
which present
s

extreme

high availability and reliability for

companies
.
Thanks to
these
,
Mainframe
s

can run at

about
99.999%
up
-
time,
with average un
planne
d downtime of under 5.3
minutes per
year.
They can also play a major
part
on disaster recovery solutions, as presented below.







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Disaster

Recovery

What
would happen
if
a
bank production
Data Center

was victim
of

a natural disaster?
Can it say to
its
customers:

“well we’re sorry but we’ve lost all your data”
?


No, it can’t be, such structures should
be able to fully recover from a disaster
, even catastrophic.

We distinguish numbers of possible disasters, there are not
that
rare, more recent
and famous

being
Terrorist
Attack
s

of
S
eptember

11
, Indonesia Tsunami, flood
s

in
W
estern Europe,
fire

in Greece
,
etc...

There really is a recrudescence of
sinister
, and companies shouldn’t neglect their

potential

effects...


43% of American
e
nte
r
prises
immediately
file for bankruptcy


after a disaster and 29% after about three years

40% of
American

e
nterprises
disappears

in less than seventy two hours

following its IT and telecoms equipments

93% of enterprises which lost significant part of their data stop have

to

stop their activities at the end of five years

U.S Bureau of Labor, U.S National Fire Protection
Agency

and Richmond House Group

To protect themselves, e
nterprise should have a BCP (Business Continuity Plan),
which is a logical
plan describ
ing

a practiced

and validated methodology
. Its then helps to fully recover from
disasters
and
to restore partially, or even better,
completely

their critical functions to continue business
process.

There are much ways to do it, but
the most efficient is to have a full
ba
ckup of
its
production
Data Center
.

It’s as if
customers
ha
d

a spare of their entire system, if you prefer.

A Distributed Systems should be very difficult to replicate

exactly.
Even if
efficient cluster solutions
exist
, they
remain

long
and complex to
conf
igure, even more if the machine
s

number is high.

Systems configurations are

one thing,
but data are other things.
They are even more important for an
enterprise, and shoul
d be replicate in another site.

When you deal with Terabytes, it’s not that easy.

Mai
nframe

infrastructure
s

offer
advanced

tested and
validated

technology which
can help
companies to create their BCP efficiently
, such as GDPS (Geographically Dispersed Parallel Sysplex)

and Metro Global Mirror
. They are able to
manage the remote copy config
uration and storage
subsystems,
to
perform failure recovery from a

SPC

(S
ingle
P
oint of
C
ontrol
)

and automate
operational task.

If customers want it
, they
can also
use XRC

(eXtended R
emote Copy),
to use a
secondary
backup
site which can be thousand

of
kilo
metres

away the primary.

This solution also allows enterprises to manage huge workloads across multiple sites.
It supports
both synchronous
and
asynchronous data
replication

for a continuous
availability
,
operations and
data
integrity
.

These technologies h
elp companies to meet their
RPO (Recovery Point Objective) and
RTO (Recovery Time Objective).
We’ll describe them

later
...
but
they
not really
seem
obsoletes, huh?






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Security

In big infrastructure, especially in banks, security is a must have. System hostin
g hot and sensible
data must then be highly secured: customers lists, account details, there are the most valuable
resources for an enterprise. Accesses must be controlled as much as possible, and
Mainframe
s

use
many technologies to do so, from hardware to

applications, passing through, of course, by the OS. Its
legacy is impressive: it benefits from about forty years of unmatched security.


The System z9 has been built on top of the security
platform that is the
Mainframe
.
It

boasts

a range of
updated an
d new security features that push
system
security

to a whole

new
level.

There is no doubt that the
Mainframe

remains the platform for secure

computing
.


Bloor

Research


LPAR

Systems
:

In
Mainframe

systems, every
logical

partition is isolated from the others
, in an
LPAR
.
If we had
to do
comparison
with x86
architectures
,
it’s like the partition
concept

in the
Xen
virtualization
system.

As a result, applications cannot overlay, write or even read code
running on the other partitions. This doesn't mean they can
't communicate each others. If
they're configured to do so, they use
HiperSocket

technology which offers

a very speed
(memory
transfer

rate) and highly secured way to communicate.


Certifications:

IBM
Mainframe

obtained a very high EAL (Evaluation Assurance

Level) for
most of its
technologies:

LPARs are certified EAL 5, and z/OS is EAL 4+, which is best rated
than the over solutions available on distributed servers. RACF (Resource Access
Control

Facility), the main security system, is also EAL 4+ thanks to i
ts LSPP (
Labelled

Security
Protection Profile) and CAPP (Controlled Access Protection Profile) achievements.


It also use other technology such IDF(Introduction Detection Service), which is a very
advanced feature built into the software stack defending th
e system against intrusion and
detecting attacks, using a special policies. It's the proof that these it can be trusted, and
explain why it's used by all government agencies.


APF
System
:

APF (Authorized Program Facility) is a program used by z/OS and MVS t
o
explicitly precise which programs can run in the system storage protection key. In fact, there
is some kind of memory which must only be used by the system. Its access is then protected,
as it contains critical data and can interact with serious part of
the OS. However, some
programs need to be executed in that memory to directly interact with the system.
Customers can thus select which product can do it or not. It avoids massive
attacks or
systems modifying. A
s a

library
specified in APF
can potentially
allow
s

users to
by pass all
RACF
authorisations
, it's very important to exactly know how many they are, who can access
them, and who can
update

APF libraries themselves.


Data
Encryption:

Mainframe
s

are designed to be secured, and they can use direct built
in
function to encrypt data. IBM has been one the first enterprise to encrypt its data, with
hardware cryptographic solutions, such as DES (Data Encryption Standard).





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It now
uses

services directly available via ICSF (Integrated Cryptographic Service Facil
ity)
which help customers to encrypt their data on tape or

other devices
.
E
ach general purpose
processor in
Mainframe
s

provide cryptographic function called CPACF (CP Assist for
Cryptographic Function), offering a huge set of featur
es which enhance the enc
ryption/
decryption performance
s
. It can be used for the popular SSL protocol.


Simplify Secure and
Audit:

In a distributed server environment, you would have to configure
each server to define your access policies. You would have to collect and
aggregate

a
ll logs
records to have a concrete and global view of the whole
data

access. The more you have
computer, the more it will take time, energy; CP time wasted, and the more humans errors
could happen. With a
Mainframe
, you only have to use
a

product such as R
ACF or Top Secret.

As data is centralized, you can also
centralize

your security. You will only need to specify your
policies on the current system. Configure it once for more, and that's it. It considerably
reduces

maintenance time and costs.
Furthermore
,
these products

can record very detailed
logs, which can be analysed to measure your whole security. More secure and more
simplified... Could you possibly ask more?


No virus and malware
:
Mainframe
s

architecture
provides

a so high level of protection and
i
solation it prevents them to be attacked. Hardware is also designed to avoid problems
caused by programming errors such as buffer overflow.
N
ote the system will not have to be
updated every months or weeks with
patches

just to be sure it will be secure. It

is already.




Scalability

World changes, a
lways,
continuously
, at a dramatic speed. If there's a thing pretty sure about IT
infrastructures, then it's that it will
always
change for sure.
Customers might be aware of that fact.

Customer’s c
omputer
s

have to
be ready to evolve with
these infrastructures
, to bring more power,
more feature, without having to reinstall an OS or buy new machines. This is the concept of
scalability: the ability to handle growing amounts of wor
k without having to be changed.


Scala
bility is the ability of a system to retain performance

levels when adding processors, memory, and storage

IBM


There are several dimensions
in
scalability,
people often think about
the load scalability,
which is
the
ability
to
accommodate higher workload
s with the current system. But there’s also the
geographic

scalability
,
which is the ability
to
have same performances regardless of
system geographical
localisations.
As a result,
you must approximately have the same
performance if your
machines are in
th
e same
room or in a more big area, as a country or even dispersed in the entire world.





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Scalability can
assured

in
both ways,
each
having

its

advantages and
defects:



Scale
Up

also called Scale
Horizontally:
you simply add more nodes to your systems. That’s
the way
most
companies

follow,
as
they’re
using distributed servers infrastructure for the
most part.
It means that
they will add power
adding a new computer.

For example, if their
three
database server can’
t handle any more transactions

because there
are
too many,
they
will add a fourth server to “help” the others.
This
seems to be a good
solution,
but
with time it horribly complexes
customer’s

infrastructure
s
.
Adding more and
more machin
es is
not
efficient, because when they’ll remain obsolete,
enterprise
s

will have
to
renew most of them


This is not
the
great
est

way
to
invest money, huh?


Mario
wants to be helpe
d
:
Scale Up!



Scale
Out

also called Scale
V
ertically
:
you
only
add needed resources to a single node of your
system.
Most of time,
it’s about memo
ry or CP.
Then,
the current system
is able to
execute
more
processes,
faster
, etc…
It
simplifies

your IT infrastructure as it doesn’t change.
Mainframe
s

are designed
for that.

Let’s
see
why this
method
is
interesting
.


Mario wants to do it
all
b
y
him
self:

Scale Out method!

In a distributed
server
architecture,
scale out is not that simple. Indeed, most of
com
puters

must
be
shutdown when you change their hardware, which mean a
significant
down
-
time

due to
maintenance
… which
mean
s

lost money.

Furthermore, im
agine you’re
in a big company

which has
plan
about twenty millions
tran
sactions per day during a week.

Let’s say
you have
more than planned, for example
about twenty five millions… you have to
react
and add power
, and quick
!

Even if you’re able to do it,
w
hat will you do
with your added CP after
this
week? They won’t be that used.
You’ve lost money

only for few day
s.
That wouldn’t have been the
case with
Mainframe
s
.






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On

the System z,
you can
add and remove CP

on the fly.
Hot
-
plug
s

on
these machines

are
very

advanced.

Then, you can add
power
when needed
for permanent or
temporary
growth
, with a
maximum of 54 CPs!

Need power? Just active a CP with the
CU
D (Capacity Upgrade on Demand)
providing the capability to non
-
disruptively add

general purposes p
rocessors
,

zAAP, zIIP, IFL or even
ICFs!

Don’t need more
power anymore?
Deactivate

them
.


Could you imagine such feature
s

in a distributed server environment, with zero down
-
time

and all
advantages it supposes
?
It’s not possible.

CUD is the only solution allowing cu
stomers to use
hardware capacity by day,
turning
it
on in needs,
turning
it
off when it
subsides and only pay for days
it’s been used.

Scalability means
processing power, but also I/O performances.
With S
ystem z, customers can
benefits from up to
512 GB of

central processor storage to
deal with
large

workloads, and up to four

LCS (Logical Channel Su
bsystems)
able to use
up to 256 channel paths to support intense
I/O

operations
.

They don’t have to worry
anymore

when their hardware will be ob
solete, as with x
86
.


With system Z, you can dynamically increase or decrease
machine
capacity

in a way that is
transparent to active applications and users.

CA

Here is the representation of a well known situation is
banks:

unplanned workloads.
CUD in action!


You should

say
that scale up
is also
important

and might be present
, and you’ll be right.

That’s why
z/VM

is
here
, and i
t

s
very inte
re
sting for scalability.
It helps
customers
to a
ccommodate growing
workloads of varying performance characteristics

in order to meet
their
business service needs.





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The
Mainframe

offers the broadest performance range of any universal server.

CA

With z/VM,
customers
can add z Linux images on the fly
to
deal with
additional new workloads

and

to offer

fault tolerance
.

It’s as if you
had
a
Data Center

in
a
box
, with
overall

power which can be
changed,
and
numbers of problems
forgotten, such as
network
connection between each server.



Migration Costs

At last but not least,
even if big infrastructures wanted to migrate to a distributed server m
odel, they
couldn’t

do it
.
Most customers
who
tried

quickly
stopped

these
kinds

of
projects
, mostly MVS to

UNIX

or even Linux operation systems
.
Rewrite program
s
, rebuild them, and
buy
a whole
new
server
farm
represents too much costs. It’s not interesting

for them
,
and
these kinds of project, when
almost succeeded, take

years to be accomplished.
E
nterprises cannot give a try to
migration, as its
repercussions

are not sure.

1
.4

What
is

its
place in IT environment
s
?

Mainframe

is the heart
of
every big
infras
tructure. It hosts
very

critical applications,
such as
transactions engines, database, etc...
It
’s used as

a
reliable

base
for
everything

and offers
many hot
services

needed by
enterprises’

core functions
.
Then
Systems such as UNIX and Linux
come as
distri
buted servers, and finally desktop running Operatin
g

System
s

such as Microsoft Windows

XP
.


Diagram resuming
the th
r
ee
IT infrastructure
pillars: from
huge
server

to desktop


Our customers devote between 60 and 80% of their budget ICT


to maintain their
Mainframe

and its applications

Gartner Group





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If you’ve always work in average
companies, you

shouldn’t

understand this place.

You should say
“it
’s wrong, systems such as Red Hat works very well, as Windows Server 2K3 if it’s greatly
administrated...” and
you’re
right;

most companies don’t need a
Mainframe
.
You’re
also
right about
the fact other Operating System
s

and hardware as newest
BladeCenter
can be reliable
.

They can be
enough

in average companies
, that’s true
.
But n
ot in the one
s

needing everything w
e talked about.

Y
ou have to
focus on the fact
that
this
thesis deal with extremely big
infrastructure

or with
enterprises which need a system
having
all advantages we
described
.
They can’t rely on system
which need to be reboot to apply patch, which don’t
have a serious support able to solve a problem
in minutes if it’s really critical, etc...

They also need a system able to run there old applications, there
payroll, all that stuff. They can do nothing but use again and again
Mainframe

computers.

Mainframe

computers are not only machine
s

used for their hardware,
technologies allowing great
Disaster Recovery Plan
or
their
“legacy side”. It’s also used in very modern
project
s
, in particular
S
erver
C
onsolidation, which
is a
concept “in the groove” nowadays.
We
will
talk
about
this one
in few
chapters
, explaining why
Mainframe

is so much interesting today, for its ability to run hundred of
Linux at the same time and on a same machine for example.

An incredibly amount of money can be
saved with
Mainframe
s

such as
the IBM System Z
,
that’s why companies invest so much
money
in
them.

Here
are

the results from
a study
which ask big companies their
strategy

about
Mainframe
s
...



Results are enough

to show that
Mainframe

is
still
the
strategic platform in which companie
s invest
in

and
also
that it’s
seeing as a system

which has its place in
the
future
, as investments
are growing.







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1
.5

The
Mainframe

market
nowadays

As d
ead

as

itself
?

Mainframe

market was really important between the 60’s and the 80’s… That’s quite
unde
rstandable;

this was the only way to have an IT infrastructure. Then came distributed server
solutions,
running Linux and Windows Server.
Numbers of specialist said
things like
“it’s over, the
Mainframe

is gonna die…
“or


This is time for modern machine and

Operating System”.
Well…

maybe
Mainframe
s

were

and continue to be
seeing as dinosaurs, but
fact is
they’re
still there, and
market is
surprisingly good
.

Market even ha
d

a growth of about 8%
last year.



Mainframe

hardware sales in the fourth quarter of 2
006 were the largest

that IBM has seen since the fourth quarter of 1998
!”

Bob Hoey,
W
orldwide vice president of
IBM
zSeries sales

Sales are successful thanks to the news
specialty engines, such as zAAP, zIIP and IFL

which we’ll talk
about in few chapters.

The new politic aiming enterprises which want to
consolidate

their servers
into a
tough

one
is
also
very good to seduce new
potentials customers.

As VMWare and Xen become
very popular, IBM wants to take back the virtualization market,

and can do it, becau
se its system use
these technology since the 70’
s with the S/370, tested and approved for years.


Mainframe

is the best solution to virtualize Linux servers. Nowadays, on a VMware machine,
customers
typically

consolidate

about
twelve

servers
.
With z/VM 5.
3,
it’
s

about hundred
.

»

Ray Jones,
Worldwide
vice

pr
e
sident
of
IBM
system Z softwares

IBM earn
s

also a lot of money with
its installed MIPS, which is a
very original way to
invoice
customers, not present on distributed
server’s

infrastructure.
It’s based
on the “on demand”
system:

customers only pay in function of the power they use.

This model is very effective.






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Sun Microsystems and its Sun Enterprise 10000 which weren’t really successful, has found a partner
in Fujitsu, creating processors for the new
Sun Fire R15K and E25K. He agrees with IBM and thinks
that
Mainframe
s

will be still used and will have a second life
in

consolidation projects.


Se
rver consolidation projects on
Mainframe

are really important, and DRP

needed by Bâle

II had a considerable

impact on our incomes. »


Jacques
-
Yves Pronier, Sun Microsystem marketing director


However, o
thers historic vendors, such as
Bull don’t believe anymore in
Mainframe
. As a result,
famous GCOS 7 and 8
won’t

be
on market anymore
, and prefer to use standard
x86 technologies.


W
e don’t use proprietary components anymore, since three years,

we
use
pressed
Intel, Xeon and Itanium
processors
on our new Nova
-
scale server range.

François Bauduin
, Bull sales director

As Bull now equips its machine with both Linux
and Windows to set up
SOA

architecture, its
customers are not really the same aimed by IBM. But it’s very interesting to see they don’t fallow the
same path, whereas they share
d

the same market few years before.


Mainframe
’s market
was quite disastrous in

the 21 century’s beginning. But
during these last years, it
impressively
gr
e
w
, especially
S
ystem
z
9 from IBM.

W
ith all the new security needs,
the 11 September
effect,
and even more huge workloads coming,
it could seriously be back.

S
erver consolidation w
ill
for sure play a major role in
sales.

Question is, will this market remain n
iches
, or will it transform into
a

visionary players
, leading

to innovations
and interest
ing

less imposing customers than now?





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2
/
Mainframe

Today:

Denver the Last Dinosaur?


No
w that you’ve understand
why
Mainframe
s

are still used and so important, you should be asking
yourself which are technologies behind all concepts
we

talked about…
You’ll probably be
disappointed as some of the
m

will
really
seem
old and archaic like JCL,
as

others
will
appear
incredibly

modern
, such as Parallel Sysplex

and Global
Mirror
.

2
.1

An impressive a
dvanced
Hardware


Y
ou should be aware than

IBM System
z

is the
most advanced and self tolerant

platform
.
Indeed,
everything in a
Mainframe

is
doubled.
As
a result, each hardware elements will
have a spare
. For
example,

i
f

a CP fails,
another one will
execute its workload

and this
operation
will be
fully
invisible.

There are two system z9

model, the Business Class, and the Enterprise Class.
Mainframe

softwar
e

can be executed on both model,
the difference is only about hardware: CP provided, Memory, etc…

As the Enterprise Class is the most interesting, we will base our study on its architecture.

IBM System z9 Hardware


First things first,
Mainframe

are used f
or their
power, and IO/capacity.
To deal with so much data,
S
ystem z9 use
s

a
CEC

(
Central Electronic Complex)
cage. You can see it as a
mother ship

where you
could
add or remove a book.

A system z9 can use up to four book
s.
Each book is interconnected with

a very high speed internal communications links and has a refrigeration subsystem to cool itself.





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Processor Book



A book is a
piece of hardware which
include

several

elements:



MCM
:
Mult
i
Chip Module
:
contains

processors
, also named “PU” for Process Unit
.

A MCM
contains
up to 12

(or 16 for S54 model)
.

However, they’re not all used, as

some
are

just
spare
s

and others as
SAP (
System Assist Proc
e
ssor); which is

a dedicated I/O processor
help
ing to

improve
performances

and reduce

the overhead of I/O processing
.

When
a
customer install its
Mainframe
, it decides to install
a specify number of books according
to
its
needs.
These books’s

CP can then be
activated

or not
, according to
its capacity
planning.

Most customers first buy books to activate few CP later, whe
n they really need power.
Why?
The more you buy
a high model (with more processors), the more IBM will
propose you

a

percent off
.


That’s a good reason, huh?
Better than
install hardware few month
s

later
.

Model

Books

MIN CP

MAX CP

Standard

SAP's

Standard

S
pares

S08

1

1

8

2

2

S18

2

1

18

4

2

S28

3

1

28

6

2

S38

4

1

38

8

2

S54

4

1

54

2

2

Each processor can be specialized, as we’ll see in next chapter



Memory
:
Clipper
memory card

u
sing DDR2 DRAM technology
, up to 128GB

per book

Physical Memory
in

book

16 GB

32 GB

48 GB

64 GB

80 GB

96 GB

112 GB

128

GB

Memory Card Config

4 x
4
GB

4x
8
GB

8
x8
GB

8x
8
GB

8x
16GB

8x
16GB

8x
16
GB

8x
16
GB




MBA

(Memory Bus Adapter)
out cards:
up to
8

per book. Each

can be
connected to

two
different
STI (Self
-
Time Interface
)
, offering
high av
ailability.





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I/O Connections

Processor Books

are directly connected to I/O

cages (up to three), via their MB out cards.

Each I/O
cage can contain
up to 28 I/O cards.
There are four types of
cards (
CHPIDS is a I/O cards «

port)



ESCON
, up to 15
CHPIDS
(16MB/
s)



FICON
, up to 4
CHPIDS
(4GB/s)



OSA
, up to 2
CHPIDS
, for network connections



Crypto Express, for encryption data process, using coprocessor


With
such design,

S
ystem
z9
has

a
very high a
vailability

I/O pr
ocessing
, and propose
s

a total system
I/O bandwidt
h of about 172
.8GB/s!

To
configure this hardware,
administrators use
a
“Support Elements” which
is an IBM Think Pad. One
is running,
the other

being

its spare.

It’s also used to operate console commands,
activate LPAR,
define network setup,
schedule an ope
ration,
inspect the system via an events monitor,
or even IPL

the machine
.
It’s then a v
ery important part of
S
ystem z9
,

offering

a nice
Java based

interface.







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Key Concepts



U
p to 512GB

memory



Up to 64 x 2.7GB/s STI
s



Up to 336 FICON channels



Up to 1024
ESCON channels



Up

to 54 Processors, each activated

remotely

and
temporarily
if needed

As every compon
ent
has
potentially
its own

spare,
this hardware offers the greatest high availability
possible in IT environment.

Each
element
, from an entire processor b
ook to
I/O cards

is

hot
-
pluggable
and never need an IPL. These features
offer
an optimum up
-
time, which
is required as a
Mainframe

should
never, ever stop, especially in banks.

IBM System z9 is the only system providing
the
ability to
activate a processor

on demand
.

It can be used both ways:



Customers
can activate it permanently.
Do to so
, one CP must be available on
a processor
book. If

so, it will cost nothing
if
its part of the contract.

If not,
customer
s

will have to pay a
new processor book and it
wi
ll
be
far more
expensive
that
if he had
bought
it
with the
Mainframe
.

People should ask why
all

processor

are not
activated
since the beginning, and it
would be
a good question.
Answer is quite simple:
most
software

used in
Mainframe

environment
has
a
pric
e based
on
the
activated
processors

number
.
Then, it’s not
interesting

for customers to use them if they are
not really
needed.

That would cost too much.



Customers can
also
activate it
temporarily
,
for one or more days. In big infrastructure
s

such
as banks
,
deal
ing

with
huge
unplanned workloads, it can

be very nice.
To execute these
workloads,
customers

activate a processor
.

This operation cost
much more than if it was a
permanent activation,
but
customers

don’t care as they only need it
for a moment, and d
on’t
want to
permanently
pay
more
software license
s
,
like
after a “normal” activation.

This power
proposed “on demand” is one of the
greatest advantage
s

of the IBM S
ystem z9.





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environments

2
.2

Specialty E
ngines


zAAP

Java based
application
s

are more and more used
in
bi
g IT infrastructure.
This
programming
language

became very popular these last years for its
reliability
and its portability.
Java applications use JVM
(Java Virtual Machine) to execute themselves,
using a JIT (Just
in

Time) compiler, converting
intermediat
e bytecode into a machine code.

It can thus be executed on many platforms such as z/OS.

As
numbers of
customer

use
Java software such as Websphere,
their

general purpose CP
s

are

utilized
by

considerable
workload
s

to execute them.

Then,
it should be very in
teresting to have
CPs which
will
only execute Java Application code.

That’s what zAAP
processor
s

propose
.

zAAP, for
IBM System z Application Assist Processors
, are specialized and dedicated processors
which provide a Java execution environment for z/OS, in

order to exclusively run Java workload code


zAAPs

are used to operate asynchronously with the others
processors which are
part of the zSeries’s Processor

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they

won’t ever need
customers to change
their Java application code
.

Every proces
sing
Java
code executed on the JVM
is
directly and
dynamically

treated
to be
dispatched on
zAAP

processor
. This function
is entirely
held by
the
IBM J
DK and PR/SM, which
make it complet
e
l
y
invisible to
IT staff, once configured.

Please also
note that
z/OS
XML System Services

can now

exploit zAAP for eligible XML workloads.

XML System Services is a new feature available since z/OS V1R8,
which offers to customers a system
-
level
XML
parser.

This function
support
s

either
zAAP
or
zIIP
in order to
benefits from
t
heir
advantages, such as
non software charges… which help
s

to save a lot of money!










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How does it work?

In fact, zAAP
s

physical architecture
s

are
very similar to the other
processors

available on zSeries, such
as IFL, zIIP and standard processors.

Then
,
only the microcode differs, in order to only execute Java
code.

As a result,
z
AAP
s

can do nothing but execute J
ava

code
,
they can’t be used to run operating
systems, to
initiate an IPL (Initial Program Load)
,
and do not support manual operation controls.

H
owever
, customers might not expect their Java performance to be improved.

zAAP
s offer

a
way to
differentiate Java workloads to others, not to improve it.


They help

to
save

critical
capacity
demands on general purpose processors.

Even if the
amount of
gene
ral purpose processor
workload

saved can vary
in function of
the Java application code really
effectively executed on zAAP
, it’s often
significant
to
be really interesting.

It also depends on the

zAAP execution mode
used
by the customer.

N
ote that
they

won
’t
support Java
software executed
under Linux
based systems such as
RHES, only on z/OS.



A zAAP processor cost about $125k in USA,
so it costs less than a
general purpose

CP
, and its
maintenance price is also lower than that of the
general purpose

CP.

It
’s thus
interesting

for
customers using Java Apps

and significant XML parsing
.






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Limitation

As for every
technology
,
zAAP
s cannot be used
without conditions
.


Then,
customers should be aware that
:



zAAP
s can be used with z/OS V1R6 minimum



zAAP
s have to be
co
nfigured
to be used within z/OS LPARs only



zAAP
s number may not exceed the general purpose CPs (active or inactive, whatever)



z9 Business Class can
handle
a maxim
um of 3 zAAP
s, Enterprise Class can deal with 27



For each zAAP

installed,
one has to own

a per
manently purchased and installed
general
purpose
CP

Why
should customer

use

it?

zAAPs enable customers to
create a specialized and more cost effective execution environment for
z/OS Java

workloads
.

Java application
s

which were once executed on general purp
ose CP
s

will be
dispatched
on
zAAP
s
.
The new “cool and hype” XML format can also be treated, during parsing
operation
by zAAP
, which will also
save
workload on general purpose processor.

As this format is
very popular and will be more and more used in big
infrastructure such as in bank
s

(
as
XML

will be
the new

format
for bank Exchange as
defined

in the SEPA project)
, this feature
is
welcome…

Customers can then purchase additional processing power
withou
t affecting their

current workloads
.
A
s

IBM does not im
pose software charges on

zAAP
s
, t
hey
then
help them to save money and
decrease TCO of their
Mainframe
, lowering the overall cost of Java based application

thought
hardware, maintenan
ce (zAAP themselves),
and
software
(MSU/MIPS used)

cost save.


Who
really
n
eed it?

In fact, most of IT environ
ment using Java
products on z/OS
might use

zAAPs
.

However, it’s not that
easy to
know if
it

will really be interesting in an
infrastructure.

As
its price is
significant
, ROI (Return
on Investment) must be
interesting
.

We
must admi
t

that
c
ost saves
vary
according to the
society
using

zAAP
s.

To help them to
project
how much they can
save

and how it will change
the way their workload will be
treated,

they can use
the zAAP Projection Tool for Java 2 Technology Edition
, which g
ives information about how much
CP
percentages

are used executing Java code, and how
a zAAP could
have
dispatched
the
Java
workload
on a
given system.
It
then should be useful to
predict

the zAAP
s

number which
are
necessary,
and
if

they are
,
to save money
and improve the System z infrastructure.







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Here is an example of
projection we can do
in order
to define
number of
zAAP
we
should use.

First
,
we
have to
use
RMF reports
to
know

how
many percentages

CPs
are

running
.


In this example,
we
general
purposes CP
s are

used at about 49% and zAAPs
would be used at about

30% if they were
equipped
.
If

this was the case
, this charge would be in the parameter

“AAP”.

With these values, we can
study workloads which run for an extended period of time, such as an
entire day
, in a 24 by 7 environment.

Let’s use an IBM known
case, with a machine using ten
processors.


During
all day long,
Java
application
s

are
used;

consuming
an average of
about 5 CPs.
zAAPs
processors would clearly be
an advantage

here
and will help to save
money.

First analysis

would
come to this
conclusion:

let’s use

5 zAAPs and 5 general
purposes

CPs
.

This could be a good solution,
but
in fact, it

s
terribly awful.
..









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environments

L
et’
s have an
other
look of the current situation





Well, it seems quite
different n
ow, huh?
During night,
batches

use

about
8 CPs.

Differences between
nights and day workloads type
appears more clearly with that chart.

The first solution
appears now
to be
incredibly
mediocre, indeed,
you should remember that
zAAPs execute nothing but

Jav
a code
.

This is what
most IT staff
s

forget

when
they’re doing their capacity planning.
As a result, with
only 5
general purposes CPs,
night batches will be
too slow, and will never be
finished
at time.

Then, you
just HAVE to
use a minimum of 8 general purp
oses
CPs to match the night’s power needs.

Two more
zAAPs will
be used to handle
the Java workload
.


With that solution
,
general purpose
CPs
will be

available to support the norma
l z/OS work as well as
the Java
workload which
will exceed

the capacity of th
e two zAAPs
.





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zIIP


Since their beginning,
the most

important thing in

big infrastructure such as

banks, with security, is
their customer records.
Without
a structured collection of their records, they couldn’t provide
financial services,
correct follow
-
up
s
, etc…

In fact, everything in our world is about collection of
data

of all kind.

That’s why Databases are
one the most
used

application;