This short paper will address an argument that exists in the WW IT marketplace today and has existed in the marketplace over the last several years. It is an argument between mainframe computing with its z/OS® operating system and distributed server implementations of UNIX® and x86 vendors. The competitors being HP, with its HP-UX operating system, Oracle (Sun) with its Solaris operating system and x86 vendors such as Dell with primarily the Microsoft® Windows® operating system. These vendors also support the Linux® operating system, albeit in a distributed fashion, and with some virtualization techniques such as VMware and Hyper-V.

1. March 2010
IBM System z, the Smarter
Mainframe
Created by
Robert Neidig/Fishkill/IBM
1-914-766-3302
neidig@us.ibm.com
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2. IBM System z, the Smarter Mainframe
Table of Contents
Introduction...................................................................................................................................2
The Challenges of Today’s Infrastructure .....................................................................................2
Today’s General Market Insight, Claims and Trends ...................................................................3
A Brief History of the Mainframe ...................................................................................................3
The Distributed IT Approach ........................................................................................................4
The ‘Smarter’ Technology Story....................................................................................................5
‘Smarter’ Virtualization Differences ...............................................................................................6
’Smarter’ Software Differences .....................................................................................................7
Green is a ‘Smarter’ Color.............................................................................................................8
‘Smarter Schools’ ..........................................................................................................................8
‘Smarter’ Security’ .........................................................................................................................9
One ‘Smarter’ Benchmark Example..............................................................................................9
Cost/Value the ‘Smarter’ Way .......................................................................................................9
A ‘Smarter’ Summary ..................................................................................................................10
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3. IBM System z, the Smarter Mainframe
Introduction
This short paper will address an argument that exists in the WW IT marketplace today and
has existed in the marketplace over the last several years. It is an argument between
mainframe computing with its z/OS® operating system and distributed server implementations
of UNIX® and x86 vendors. The competitors being HP, with its HP-UX operating system,
Oracle (Sun) with its Solaris operating system and x86 vendors such as Dell with primarily
the Microsoft® Windows® operating system. These vendors also support the Linux® operating
system, albeit in a distributed fashion, and with some virtualization techniques such as
VMware and Hyper-V.
We will compare these distributed server implementations against the IBM System z®
mainframe in a variety of ways. We will look at the value propositions of each platform in
terms of such attributes as architecture, design, technology, systems management and
investment protection. We will also look at scalability, capacity, performance (both
uniprocessor and multiprocessor), reliability, availability and serviceability, virtualization,
environmentals, operating system and middleware software, openness, security, business
resiliency, and last but not least, cost.
In general, the argument for the mainframe versus distributed servers centers around several
topics, one of which is the sharing of resources. This sharing of resources simply provides
better overall efficiencies thereby enabling better economies of scale. This shared resource
approach of the mainframe also enables a more consolidated approach to computing. This
consolidated approach allows more work to be done on one server versus work being done on
multiple distributed servers networked together. Another mainframe benefit is the ability of
having all the data in one place versus having many copies of the data spread among many
distributed servers. High availability is also achieved by the built-in failure avoidance and
recovery functions within the mainframe. High availability in a distributed environment can
be achieved by having redundancy of multiple servers and failover configurations at
additional cost.
The Challenges of Today’s Infrastructure
Today the need for progress is quite clear. We need to be smarter in our implementation of
IT. The IBM System z ‘mainframe’ is a key component in this venture as we move into the
future and also enhances today’s infrastructure with a smarter mainframe versus distributed
environments. For example, up to $93 billion dollars in total sales is lost each year because
retailers don’t have the right products in stock to meet their customer demand.
Approximately 170 billion kilowatt-hours is wasted each year by consumers due to
insufficient power usage information. Up to $25 billion dollars in global trading systems are
under extreme stress, handling billions of market data messages each day. Seventy cents per
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4. IBM System z, the Smarter Mainframe
$1 dollar, on average, is spent on maintaining current IT infrastructures versus adding new
capabilities. Approximately 33% of consumers notified of a security breach will terminate
their relationship with the company they perceive as responsible. The information and data
explosion continues and is driving about 54% growth in storage shipments every year.
Today’s General Market Insight, Claims and Trends
The following data points are examples of the impact that System z has had on the IT market
place over the last few years. As of October 20, 2009, System z delivered nine percent MIPs
growth over the last 24 months. According to IDC, System z has maintained revenue
leadership in the WW $250K+ server segment with a 31.4% share. System z led #2 HP by 14
points for 2Q09. According to Gartner, System z held its #1 position at a 36.6% share for
2Q09. Installed capacity of specialty workload engines continues to grow rapidly. Comparing
the first half of 2008 to the first half of 2007, Linux engines (IFL) grew ~30%, Java™ engines,
the IBM System z Application Assist Processor (zAAP) grew ~49% and the IBM System z
Integrated Information Processor (zIIP) specialty engines grew at ~141%.
A Brief History of the Mainframe
On April 7, 1964, the IBM Corporation launched the System/360™ into the marketplace. This
system addressed the many workloads that existed with a new single architecture and family
of systems unlike we had seen. The S/360™, a system designed for business computing, which
took four years to develop and cost ~$5 billion (~$24 billion today) was an enormous and
risky undertaking. Thomas Watson Jr. literally “bet his company” on the project. The S/360
has been ranked as one of ‘the’ major business accomplishments in American history
alongside of Ford’s Model T and Boeing’s 707. It was the first time in history that a complete
line of computers and operating systems was announced at one time. The S/360 architecture
was the first architecture to combine both commercial and scientific architectures with a
universal instruction set designed to execute multi-user, multi-function, batch, and on-line
transactional programs with an intelligent off-loaded I/O subsystem.
This architecture also allowed new and exciting sets of events to occur. For example, a
program written in 1965 in COBOL can still run today along side of code written just
yesterday, and many of those programs are still running. This was a very significant
achievement in ‘investment protection’ and no other vendor can make a claim that comes
close. Also, imbedded in the architecture was another innovative ‘protection and integrity’
mechanism. A program could not corrupt any other program on the same system because a
function called ‘storage protect’ was implemented within the architecture and continues to
execute today. In addition, program integrity was also built in on ‘day one’ with isolation of
supervisor state and problem program state. Since then, many innovative functions and
features have been woven into the S/360, the S/370™ the S/390® and into today’s modern
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5. IBM System z, the Smarter Mainframe
IBM System z10™. Today’s System z mainframe includes major memory enhancements,
virtual memory enhancements, major processor enhancements and many significant
input/output enhancements. It can also be configured into today’s modern and shared
Parallel Sysplex® environment, and also a two and/or three site multi-data center
Geographically Dispersed Parallel Sysplex™ (GDPS®) environment providing the highest form
of availability.
The Distributed IT Approach
Distributed systems on the other hand, provide more of a silo-oriented approach to
computing and a typically ‘non-shared’ approach in managing resources, although VMware
and Hyper-V virtualization products have helped with this issue. In older distributed
environments, one server had run just one application until the introduction of VMware and
Hyper-V. Today, VMware and Hyper-V techniques allow one server to run multiple
applications, but we still see some distributed ‘server farms’ or ‘server plantations’ in many
installations.
Regarding availability, most distributed operating systems do not contain much or any
recovery code. In addition to lack of recovery code, most non System z servers (other than
POWER) lack a significant amount of recovery hardware as well. If the operating system
suffers a problem, the typical response is to ‘reboot’ the system. Today’s IBM’s z/OS
operating system, going all way back to MVS™, has recovery code called ‘Functional
Recovery Routines’ for every major routine in the system. If a problem were to occur, the
operating system has the ability to refresh the code and keep the system up and running.
Since many outages are a result of software hits or operator error, System z enjoys a most
reliable system, a high degree of automation, and the highest forms of availability on the
planet. z/OS also has an automated restart manager (ARM) which can restart the right pieces
on an available LPAR. Recent releases of z/OS extend its high availability characteristics by
going beyond failure detection to predicting problems before they occur. z/OS systems are
designed to learn heuristically from their own environment to anticipate and report on system
abnormalities using Predictive Failure Analysis (PFA). Essentially, PFA can help customers
avoid soft failures leading to outages. Distributed systems are normally refreshed when server
upgrades are required, causing unnecessary outages and processing disruptions. System z
processors can be added dynamically with functions such as CUoD, CIU, On/Off Capacity on
Demand and Dynamic Provisioning.
In addition, Capacity Back Up for temporary additional processing power for every type of
System z processor including GPs, IFLs, zIIPs, and zAAPs is fully supported. There is also the
issue of the actual number of servers that is really needed. Many cost/value studies have
shown that a distributed solution could require 3 to 4 times the number of servers that a
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6. IBM System z, the Smarter Mainframe
production environment requires. These additional distributed servers are required to address
workloads such as test/development/QA and D/R. All these workload requirements can
reside within a single System z system using existing virtualization techniques like z/VM® and
PR/SM™ LPAR, which are common to most System z configurations. Regarding server
utilization, distributed servers typically run at lower utilization rates of 5 % to 30%, and
sometimes higher with the help of VMware and Hyper-V, depending on the workload,
although these hypervisors do not necessarily contribute to productive application cycles.
System z, on the other hand, normally runs anywhere from 85% to 100% utilization.
The ‘Smarter’ Technology Story
Today’s IBM System z10 Enterprise Class (z10 EC™) has a processing engine (and up to 77 of
them) that runs at 4.4 GHz on a quad core chip. If you put 64 of these processors together
you will get a single-image 64-way Multi-processor running one copy of z/OS. Most
distributed processors today are in the~2.0 to 3.0 GHz range. Itanium technology only runs at
1.5-1.7 GHz and even the current Nehalem technology (Nehalem-EP) is estimated at about
~2.7 GHz. System z has also implemented ‘specialty engines’ for a decade. These include the
System Assist Processor (SAP) for handling I/O offloads, the Integrated Facility for Linux
(IFL) for executing Linux workloads, the IBM System z Integrated Information Processor
(zIIP) for processing a variety of workloads including functions like DB2® star schema
queries, DB2 Utilities, IPSEC the security code for TCPIP, and the System Data Mover (SDM)
code for the system data mover function for extended data mirroring, z/OS Global Mirror
(XRC). Additionally there is the IBM System z Application Assist Processor (zAAP) for
executing Java code, and also the Integrated Coupling Facility (ICF) for executing Coupling
Facility Control Code in a Parallel Sysplex configuration. Distributed systems do not have
these forms of specialty engines for handling particular workloads.
When we discuss Input/Output operations, the IBM System z has an extremely powerful and
robust I/O subsystem. The System z10 EC has up to 1024 I/O channels that can run up to a
FICON® rate of 8 Gbit/s each (there are 336 FICON channels available, also with a new High
Performance Feature (HPF) capability for even higher bandwidth). There are up 1024
ESCON® Channels for the traditional fiber optic support. For seamless connections to the
network and the internet, there are Open Systems Adapters (OSA Express) that can run up to
10Gbit/s each, providing very high bandwidth. In addition, Dynamic Channel-Path
Management is a capability designed to dynamically adjust the channel configuration in
response to shifting workload patterns. It is a function in the Intelligent Resource Director
(IRD) working together with the Workload Manager of z/OS. To address data security, there
are Crypto Express processors which provide secure key encryption/decryption and also can
process up to 16,000 SSLs/sec/adapter.
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7. IBM System z, the Smarter Mainframe
The capacity of a single fully-loaded System z10 EC is about~30+K MIPs and if one were to
couple these together in a Parallel Sysplex configuration, with up to an architectural limit of
32 nodes, you could scale to a very, very large system, indeed.
Memory management on System z is the best in the industry. System z implements an overall
highly available and reliable memory management approach, a very high performance paging
subsystem and excellent memory over commit ratios. System z z/VM over commit ratios have
achieved 4:1 ratios and higher. X86 with VMware can provide up to a typical ratio of 2:1.
Today’s System z also has up to 1.5TBs of real memory available. System z also has a
HiperSockets™ function, or network (TCPIP) in a box, which enables data from one LPAR to
be transferred to another LPAR securely, using the memory bus at very high speed.
‘Smarter’ Virtualization Differences
System z has had virtualization capability since 1967 with the implementation of the CP67.
This virtualization technique has been enhanced over the years to today’s System z ‘two
dimensional’ virtualization approach with PR/SM LPAR logical partitioning and the z/VM
hipervisor. Up to 60 logical partitions can be created within a single System z and with those
LPARs which typically run the flagship operating System z/OS, you can also create additional
LPARs which run z/VM as a hypervisor and support hundreds and hundreds of virtual Linux
servers within a single LPAR.
VMware and Hyper-V are relatively new to the distributed environment providing an
increased degree of virtualization, but with some architectural limitations and some possible
security/integrity issues. Regarding scale, VMware VSPHERE 4 now supports a maximum of
8 cores per guest image as opposed to a previous 4 cores, and limits virtual machines to 255
GB of virtual memory. System z supports 64 cores per virtual machine. VMware also does not
support any dedicated I/O. Hyper-V supports up to 4 cores per guest image but without a
Dynamic Memory feature, and also has a dependency on a copy of Windows Server 2008,
which could be a single point of failure.
Regarding security and integrity, as installations implement virtualization techniques like
VMware and Hyper-V, they need to understand that not all hypervisors provide the same level
of security. There have been reported instances with VMware whereby a guest virtual
machine can exploit the host and invoke code to run on that host. That host has been
rendered vulnerable. System z, on the other hand, provides protection in its hypervisor for
both LPAR and z/VM to prevent these types of exploits. A program running in a partition on
System z cannot disrupt the LPAR hypervisor, alter its contents, or use the hypervisor to
insert data or executable code in another LPAR. There is also no need for costly weekly or
monthly security patches as in the case of other non System z operating systems.
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8. IBM System z, the Smarter Mainframe
Using System z with z/VM virtualization, quite a few consolidation examples have been cited.
To name a few, one can consolidate many workloads onto a single IBM System z mainframe,
just one footprint can allow a replacement of UNIX or x86 processors at ~10 - 28 to 1 IFL
ratio and also reduce UNIX and x86 OTC software support costs also at ~10 - 28 to 1 ratio.
Another example of consolidation showed Linux on an IBM System z10 Business Class™ (z10
BC™) with 5 IFLs that was able to consolidate up to 134 unvirtualized Sun x2100 2.8 GHz
servers.
’Smarter’ Software Differences
System z is supported by a number of different operating systems. Among them, z/OS, the
flagship operating system with its immense scale and reliability widely used in today’s large
OLTP and commercial environments. Also, the z/VSE operating system supports the many
smaller and medium sized customers for System z. There is support for z/VM, the ultimate in
virtualization hypervisors. TPF and z/TPF is also supported for very high transaction oriented
systems, and Linux for z is supported for today’s many modern and open environments.
Economically, it is much more inexpensive to run one or two copies of software than running
hundreds of copies as is the case with distributed environments. It is also much easier to
operate and maintain one or two copies of software versus dozens or hundreds as may be
needed in a distributed environment. The IBM portfolio of software, in addition to its
operating systems support, consists of a huge set of programs divided into five distinct areas:
Rational®, for application development, WebSphere® for transaction processing and internet,
Information Management for managing data, Lotus for interactive and collaborative
computing, and Tivoli® for overall systems management.
IBM has recently announced ‘Solution Editions’ in 2009 for several of its major workloads,
providing a more economical and lower cost to run these workloads with legendary
mainframe quality, security, availability, scale and all priced to be competitive with UNIX
alternatives. Solution Editions exist for Data Warehousing, SAP, ACI, WebSphere, Security,
GDPS, Enterprise Linux Server, Chordiant and Cloud Computing.
http://www-03.ibm.com/systems/z/solutions/editions/index.html
With regard to programs for System z from Independent Software Vendors (ISVs), there are
now 1,675 ISVs developing code on System z as of year end 2009, with 175 new ISVs being
added last year. There are now over 6,200 applications available for System z with over 900
new System z applications and tools being added in 2009. 2,732 applications are now enabled
on z/OS 1.8 and above. There are 1,300 applications enabled on z/OS 1.10 and 375
applications enabled on z/OS 1.11. There were 550 new applications added for Linux on z in
2009 with a total now of 3,150 applications being supported on the platform.
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9. IBM System z, the Smarter Mainframe
http://www.ibm.com/systems/z/os/zos/software/isv110.html
http://www.ibm.com/systems/z/os/zos/software/isv111.html
Green is a ‘Smarter’ Color
IBM is in the process of a large transformation of its thousands of internal UNIX systems
being consolidated on to a couple of dozen System z with its ‘Project Big Green’. IBM used
the very popular ‘RACE’ (Right-Fitting Applications into Consolidated Environments)
financial methodology to build the business case for this project. This multi-year
transformation and consolidation project began in 2007 and continues in 2010. IBM is
planning to save millions of dollars in floor space alone, with an 85% reduction being realized
and an 80% reduction in energy usage.
The following are some environmental examples and results we have seen in consolidating
onto a mainframe platform: The IBM System z10 BC offers a 113% improvement in
performance per KWh over its predecessor IBM System z9® Business Class (z9 BC). A z10 BC
may provide up to 16 times the work for the same power consumption of 14 Sun Fire x2100
2.8 GHz servers. With an Opteron server utilized at 10%, a 10 way System z BC at a 90%
typical utilization can do the equivalent work of 232 Opteron processor cores with an 83%
smaller footprint and up to 93% lower energy costs. One IBM System z10 Enterprise Class
(z10 EC™), compared to an HP Superdome, uses less that 1/3 the watts on comparable
workloads for total power and cooling, at less than 1/3 the cost. On average, even the latest
generations of distributed servers use 4X the energy for the same workload as a z10™. An
example is that 8 Sun 64W M8000s were required for what could be done on a z10 with 35
IFLs.
‘Smarter Schools’
For the past seven years IBM has been supporting its ‘Academic Initiative’ by providing
System z mainframe education for our younger and upcoming professionals at many colleges
and universities around the globe. The Academic Initiative is world-wide program, supported
by many IBM brands and technologies. It encourages open standards and open source and
provides easy access to hardware, software, courses, textbooks and other IT resources. We
have conducted numerous System z mainframe contests around the world. We have
succeeded in training over 65,000 students enrolled at over 643 schools on System z
technology and architecture, surpassing the original goal of 20,000 students trained by the
end of 2010.
http://www.ibm.com/developerworks/university/academicinitiative/
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‘Smarter’ Security’
The IBM System z has, what I like to call, a complete security architecture built into it which
goes all the way back to the original S/360 architecture announced and delivered in 1964.
Storage protection was achieved with the implementation of ‘storage protect keys’, this again
is the ability not to overlay or write into another memory space belonging to another user,
and continues to be an integral part of the System z architecture today. The IBM System z
also enjoys the following with respect to ‘data privacy’: Data encryption with both clear key
and secure key, tape encryption, disk encryption, secured key and storage management, and a
data base oriented multi-level security (MLS) function using a combination of z/OS and DB2.
With regard to ‘platform infrastructure’ System z is the only server that has achieved the
Common Criteria EAL 5 certification. System z also supports a whole host of functions such
as z/OS Java SDK, RACF®, ICSF, ITDS, Network Authentication Services, z/OS SSL, z/OS
Communications Server and PKI Services. Regarding ‘compliance and audit’ the IBM System
z supports SMF, the IBM Tivoli Security Compliance Insight Manager, the IBM Tivoli
zSecure Suite, and the DB2 Audit Management Expert. For the ‘extended enterprise’
System z supports the Tivoli Identity Manager and the Tivoli Federated Identity Manager. On
the other hand, many distributed solutions do not even come close to this set of products and
system capabilities. None of them have anything close to ‘storage protect’, and their data
encryption is typically an ‘add-on’ in the channel. Their operating systems are just starting to
implement some security and integrity features that have been on the mainframe for many
years.
One ‘Smarter’ Benchmark Example
IBM ran a benchmark for Domino® which produced some staggering results. An IBM System
z10 EC running Domino R8.5 with 64-bit support and Linux supports 75,000 users per 30
square feet, or 2,500 users per square foot. This is 75,000 users per 7,300 watts, or
approximately 10 users per watt. This is over 1,000 users for the energy of a 100 watt bulb.
The System z10 EC with 8 IFLs can support 90,000 active Domino 64-bit users and Linux on
System z users. One System z10 BC will support up to 70,000 active Domino Benchmark
users, and you need to add merely one Domino IFL for up to another 7,500 users. This
benchmark was conducted at the Washington Systems Center in September 2008.
Cost/Value the ‘Smarter’ Way
IBM has conducted hundreds and hundreds of cost/value studies using several methodologies
such as ‘Scorpion’ studies, ‘RACE’ studies and ‘Eagle’ studies. Most of these studies have
concluded that the System z value proposition is the most inexpensive way to implement IT
today versus a distributed one. When a study is implemented, one of the key items to
ascertain is to make sure we obtain all of the data that make up an IT solution or
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environment. This includes the following: installed hardware inventory, all software licenses
implemented, both operating systems and middleware, all maintenance costs and
support/subscription costs, disk storage and maintenance costs, all environmental costs such
as power, floor space and cooling costs, all network costs and all administration costs. Once
these costs items have been collected and agreed upon, a study can be initiated using all
customer data and the output played back to the customer typically showing a solid business
case for the mainframe. Some data also shows some surprises, like a distributed network cost
of up to 3 to 4 times of a mainframe, just to cite just one example.
A ‘Smarter’ Summary
When it comes to ‘smarter’ computing and implementation of new workloads or modernizing
existing workloads, the obvious, the safest, the least risk and overall best choice is today’s
‘smarter’ mainframe, the IBM System z.
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12. IBM System z, the Smarter Mainframe
Copyright IBM Corporation 2010
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Produced in the United States of America,
03/2010
All Rights Reserved
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All statements regarding IBM’s future direction and intent are subject to change or withdrawal without notice,
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Performance is in Internal Throughput Rate (ITR) ratio based on measurements and projections using
standard IBM benchmarks in a controlled environment. The actual throughput that any user will experience
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ZSW03162-USEN-02
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