IBM ^ zSeries 800 and z/OS, z/OS.e, z/VM and VSE/ESAReference Guide
The IBM ^ zSeries is one of the fi rst enterprise-
class platform optimized to integrate business applications
and to help meet the critical transactions and demands
of the e-business world far into the twenty-fi rst century.
The IBM ^ zSeries servers are designed to provide
these capabilities through a totally new system design
based on z/Architecture announced in October 2000 with
the IBM ^ zSeries 900 (z900).
The IBM ^ zSeries 800 (z800) servers use the
functional characteristics of the z900 in a package that is
designed to deliver excellent price/performance for those
requiring zSeries functionality with a lower capacity entry
point than that offered by z900.
The z800 offers ten General Purpose models, from a sub-
uni to a four-way, which can operate independently or as
part of a Parallel Sysplex cluster. There is a Coupling
Facility model and also a Dedicated Linux model on which
one to four engines can be enabled for the deployment of
The z800 takes advantage of the robust zSeries I/O sub-
system. High speed interconnects for TCP/IP communi-
cation, known as HiperSockets, let TCP/IP traffi c travel
between partitions at memory speed rather than network
speed. A high-performance Gigabit Ethernet feature is one
of the fi rst in the industry capable of achieving line speed:
1 Gb/sec. The availability of Native FICON devices, Fibre
Channels (FCP channels), 2 Gigabit per second links
and cascaded FICON directors can increase I/O perfor-
mance, simplify/consolidate channel confi gurations and
help reduce the cost of ownership.
The z800 benefi ts from the Intelligent Resource Director
(IRD) function, which directs resources to priority work. The
IRD function combines the strengths of key technologies:
z/OS, Workload Manager, Logical Partitioning and Parallel
Unique to the z800 is z/OS.e, a specially priced offering
for z/OS, providing select function at an exceptional price.
z/OS.e is intended to help customers exploit the fast growing
world of next generation e-business by making the deploy-
ment of new applications on the z800 very attractively
priced. z/OS.e uses the same code as z/OS, customized
with new system parameters, and invokes an operating
environment that is comparable to z/OS in service, man-
agement, reporting, and reliability. Also, z/OS.e invokes
key z800 hardware functionality that you would get from
z/OS. As a result, unless otherwise specifi ed, zSeries hard-
ware functionality described herein is applicable to both
z/OS and z/OS.e running on a z800 server.
While z/OS.e is unique to the z800, all existing zSeries
operating systems such as z/OS, z/VM and Linux are
supported and will be discussed later.
New Tools for Managing e-business
The IBM ^ product line is backed by a comprehen-
sive suite of offerings and resources that are designed to
provide value at every stage of IT implementation. These
tools can help customers test possible solutions, obtain
fi nancing, plan and implement applications and middle-
ware, manage capacity and availability, improve perfor-
mance and obtain technical support across the entire
infrastructure. The result is an easier way to handle the
complexities and rapid growth of e-business. In addition,
IBM Global Services experts and IBM Business Partners
can help with business and IT consulting, business trans-
formation, total systems management services, as well as
customized e-business solutions.
Ease of Use and Self-Management
To help organizations deal effectively with complexity, IBM
provides a blueprint for autonomic computing which will
help enable self-managing, self-optimizing, self-protecting
and self-healing functions for systems. The goal is to use
technology to manage technology, creating an intelligent,
self-managing IT infrastructure that minimizes complexity
and gives customers the ability to manage environments
that are hundreds of times more complex and more
broadly distributed than exist today. This enables
increased utilization of technology without the spiraling
pressure on critical skills, software and service/support
The IBM autonomic computing initiative represents a major
shift in the way the industry approaches reliability, avail-
ability and serviceability (RAS). It harnesses the strengths
of IBM and its partners to deliver open, standards-based
servers and operating systems that are self-confi guring,
self-protecting, self-healing and self-optimizing. The object
of autonomic computing technology is to help ensure that
critical operations continue without interruption and with
minimal need for operator intervention.
The goal of autonomic computing is to help customers
dramatically reduce the cost and complexity of their
e-business infrastructures, and overcome the challenges
of systems management. The zSeries product line plays a
major role in autonomic computing, since the self-manage-
ment capabilities available for the zSeries will function
as a model for other IBM ^ platforms, such
as IBM ^ xSeries, IBM ^ iSeries and
IBM ^ pSeries.
zSeries servers and z/OS provide the ability to confi gure,
connect, extend, operate and optimize the computing
resources to help effi ciently meet the always-on
demands of e-business.
One of the key functions of z/OS is the Intelligent Resource
Director (IRD), an exclusive IBM technology that makes
the z800/z900 servers capable of automatically reallocat-
ing processing power to a given application on the fl y,
based on the workload demands being experienced by
the system at that exact moment. This advanced tech-
nology, often described as the living, breathing server,
allows the z800/z900 with z/OS to provide nearly unlimited
capacity and nondisruptive scalability to z/OS and non-
z/OS partitions such as Linux, according to priorities deter-
mined by the customer.
Although z/VM does not specifi cally support the IRD,
capabilities are provided for managing guest performance
to help achieve customer-defi ned goals. A new service
virtual machine, the Virtual Machine Resource Manager
(VMRM), accepts workload defi nitions, goal specifi cations,
and associations between them. Virtual machine CPU and
I/O performance controls are adjusted based on actual
performance to attempt to achieve the goals associated
with each workload. Additionally, I/O management facilities
have been added that enable z/VM to exploit the hardware
I/O Priority Queuing facility to prioritize guest and host
I/O operations. A virtual equivalent of the hardware facility
is provided, allowing virtual machines running operating
systems such as z/OS that exploit I/O Priority Queuing to
determine the priority of their I/O operations within bounds
defi ned by a new SET IOPRIORITY command. z/VM will
automatically set a priority for I/O operations initiated by
virtual machines that do not exploit this function.
The zSeries is based on the z/Architecture, which is
designed to eliminate bottlenecks associated with the
lack of addressable memory and automatically directs
resources to priority work through Intelligent Resource
Director (IRD). The z/Architecture is a 64-bit superset of
This architecture has been implemented on the zSeries
to allow full 64-bit real and virtual storage support. A maxi-
mum 32 GB of real storage is available on z800 servers.
zSeries can defi ne any LPAR as having 31-bit or 64-bit
64-bit general registers.
New 64-bit integer instructions. Most ESA/390 architec-
ture instructions with 32-bit operands have new 64-bit
and 32- to 64-bit analogs.
64-bit addressing is supported for both operands and in-
structions for both real addressing and virtual addressing.
64-bit address generation. z/Architecture provides 64-bit
virtual addressing in an address space, and 64-bit real
64-bit control registers. z/Architecture control registers
can specify regions, segments, or can force virtual
addresses to be treated as real addresses.
The prefi x area is expanded from 4K to 8K bytes.
New instructions provide quad-word storage consistency.
The 64-bit I/O architecture allows CCW indirect data
addressing to designate data addresses above 2 GB for
both format-0 and format-1 CCWs.
IEEE Floating Point architecture adds twelve new instruc-
tions for 64-bit integer conversion.
The 64-bit SIE architecture allows a z/Architecture server
to support both ESA/390 (31-bit) and z/Architecture
(64-bit) guests. Zone Relocation is expanded to 64-bit
for LPAR and VM/ESA.
Use of 64-bit operands and general registers for all
Cryptographic Coprocessors instructions and Peripheral
Component Interconnect Cryptographic Coprocessors
(PCICC) instructions is added.