A single-frame IBM z15 mainframe. Larger capacity models can have up to four total frames. This model has blue accents, as compared with the LinuxONE III model with orange highlights.
A single-frame IBM z15 mainframe. Larger capacity models can have up to four total frames. This model has blue accents, as compared with the LinuxONE III model with orange highlights.
An IBM z14 mainframe. It is distinguished from the LinuxONE model by the blue accents on the doors.
An IBM z14 mainframe. It is distinguished from the LinuxONE model by the blue accents on the doors.
A pair of IBM mainframes. On the left is the IBM z13 (while the naming was changed, the z13 line had a zSystems label on doors). On the right is the IBM LinuxONE Rockhopper.
A pair of IBM mainframes. On the left is the IBM z13 (while the naming was changed, the z13 line had a zSystems label on doors). On the right is the IBM LinuxONE Rockhopper.

IBM Z[1] is a family name used by IBM for all of its z/Architecture mainframe computers. In July 2017, with another generation of products, the official family was changed to IBM Z from IBM z Systems; the IBM Z family now includes the newest model, the IBM z16, as well as the z15, the z14, and the z13 (released under the IBM z Systems/IBM System z names), the IBM zEnterprise models (in common use the zEC12 and z196), the IBM System z10 models (in common use the z10 EC), the IBM System z9 models (in common use the z9EC) and IBM eServer zSeries models (in common use refers only to the z900 and z990 generations of mainframe).

Architecture

The zSeries, zEnterprise, System z and IBM Z families were named for their availability – z stands for zero downtime. The systems are built with spare components capable of hot failovers to ensure continuous operations.[2]

The IBM Z family maintains full backward compatibility. In effect, current systems are the direct, lineal descendants of the System/360, announced in 1964, and the System/370 from the 1970s. Many applications written for these systems can still run unmodified on the newest IBM Z system over five decades later.[3]

Virtualization

Virtualization is required by default on IBM Z systems. First layer virtualization is provided by the Processor Resource and System Manager (PR/SM) to deploy one or more Logical Partitions (LPARs). Each LPAR supports a variety of operating systems. A hypervisor called z/VM can also be run as the second layer virtualization in LPARs to create as many virtual machines (VMs) as there are resources assigned to the LPARs to support them. The first layer of IBM Z virtualization (PR/SM) allows a z machine to run a limited number of LPARs (up to 80 on the IBM z13). These can be considered virtual "bare metal" servers because PR/SM allows CPUs to be dedicated to individual LPARs. z/VM LPARs allocated within PR/SM LPARs can run a very large number of virtual machines as long as there are adequate CPU, memory, and I/O resources configured with the system for the desired performance, capacity, and throughput.[citation needed]

IBM Z's PR/SM and hardware attributes allow compute resources to be dynamically changed to meet workload demands. CPU and memory resources can be non-disruptively added to the system and dynamically assigned, recognized, and used by LPARs. I/O resources such as IP and SAN ports can also be added dynamically. They are virtualized and shared across all LPARs. The hardware component that provides this capability is called the Channel Subsystem. Each LPAR can be configured to either "see" or "not see" the virtualized I/O ports to establish desired "shareness" or isolation. This virtualization capability allows significant reduction in I/O resources because of its ability to share them and drive up utilization.[citation needed]

PR/SM on IBM Z has earned Common Criteria Evaluation Assurance Level (EAL) 5+ security certification,[4] and z/VM has earned Common Criteria EAL4+ certification.[5]

The KVM hypervisor from Linux has also been ported.[6]

List of models (reverse chronological order)

Since the move away from the System/390 name, a number of IBM Z models have been released. These can be grouped into families with similar architectural characteristics.

IBM z16

The IBM z16[7] mainframe, based on the Telum processor, was introduced on April 5, 2022.[8] The instructions for AI and neural nets are described in a new edition[9] of the z/Architecture Principles of Operation.

IBM z15

IBM z14

The dual frame z14, launched in July 2017,[13] and the single frame launched in April 2018,[14] are based on the z14 chip, a 5.2 GHz 10-core processor.[15][16] A z14 system can have a maximum of 240 Processing Unit (PU) cores, 170 of which can be configured to the customer's specification to run applications and operating systems, and up to 32 TB usable redundant array of independent memory (RAIM), some of which can be configured as Virtual Flash Memory (VFM). Each PU can be characterized as a Central Processor (CP), Integrated Firmware Processor (IFP), Integrated Facility for Linux (IFL) processor, Integrated Information Processor (zIIP), Internal Coupling Facility (ICF) processor, additional System Assist Processor (SAP) or as a spare. The focus of the IBM Z systems are pervasive encryption as the z14 processor has plenty of hardware assisted cryptography features (AES, DES, TDES, SHA, Random number generator).[17][16]

IBM z13

Launched on January 13, 2015,[18][19] the z13 is based on the z13 chip, a 5 GHz 8-core processor. A z13 system can have a maximum of 168 Processing Unit (PU) cores, 141 of which can be configured to the customer's specification to run applications and operating systems, and up to 10144 GiB (usable) of redundant array of independent memory (RAIM). Each PU can be characterized as a Central Processor (CP), Integrated Firmware Processor (IFP), Integrated Facility for Linux (IFL) processor, z Integrated Information Processor (zIIP), Internal Coupling Facility (ICF) processor, additional System Assist Processor (SAP) or as a spare. The z Application Assist Processor (zAAP) feature of previous zArchitecture processors is now an integrated part of the z13's zIIP.[20]

The z Systems z13s (2965 series) was introduced on February 17, 2016[21]

The z13 and z13s introduce a new vector architecture and are the last z Systems servers to support running an operating system in ESA/390 architecture mode.[22]

IBM zEnterprise System

A trio of IBM zEnterprise mainframe computers. From left to right: EC12, BC12, Bladecenter Extension.
A trio of IBM zEnterprise mainframe computers. From left to right: EC12, BC12, Bladecenter Extension.

This line has two generations: first generation, released in 2010/2011 with 114 single-rack ("business class") and 196 ("Enterprise class") models; and released in 2012/2013 second generation, branded as generation 12 of main line, and released with two model lines: single-rack zBC12 and dual-rack zEC12.

zEnterprise gen2 (zBC12 and zEC12)

An IBM zEnterprise EC12 with the cover removed. The interior is lit to better see the various internal parts.
An IBM zEnterprise EC12 with the cover removed. The interior is lit to better see the various internal parts.

On April 8, 2014, in honor of the 50th anniversary of the System/360 mainframe, IBM announced[23] the release of its first converged infrastructure solution based on mainframe technology. Dubbed the IBM Enterprise Cloud System,[24] this new offering combines IBM mainframe hardware, software, and storage into a single system and is designed to compete with competitive offerings from VCE, HP, and Oracle. According to IBM, it is the most scalable Linux server available with support for up to 6,000[23] virtual machines in a single-footprint. In June 2014, IBM announced[25] it had shipped its first Enterprise Cloud System to Vissensa, a UK-based managed service provider.

zEnterprise Business Class 12 - The zBC12 is a entry-level single-rack solution, was introduced in July 2013 and is available in two hardware models, the H06 and the H13. It's designed to serve the mid-range business segment and can be configured to be a Linux virtualization server, in a version called the Enterprise Linux Server. The H13 has 18 processor cores, with up to 13 configurable. The H06 has nine, with up to six configurable.

zBC12 models
Model CPs IFLs zAAPs / zIIPs ICFs SAPs IFPs Spares zBX Memory (GB)
H06 0–6 0–6 0–4 / 0–4 0–6 2 1 0 0–1 8–240
H13 0–6 0–13 0–8 / 0–8 0–13 2 1 2 0–1 16–496

Introduced in July 2013, the zEnterprise BC12 is based on an upscaled z114, running 18 zEC12 processors at 4.2 GHz and up to 489 GB RAM. It is available in two models, the H06 and the H13 with one and two processing drawers respectively. The zBC12 can connect to the zBX expansion system. IBM is offering a special version of the zBC12 called the Enterprise Linux Server,[26] running only Linux hosts on top of its z/VM hypervisor, targeting large migrations from x86-based Linux installations.

zEnterprise Enterprise Class 12 - The zEC12 is a high-end dual-rack solution, and available in five hardware models: H20, H43, H66, H89 and HA1.[27] The model number is based on the number of cores available for customer workloads. Additional cores are reserved as spares, SAPs and IFPs.

zEC12 models
Model CPs IFLs zAAPs / zIIPs ICFs SAPs IFPs Spares Memory (GB)
H20 1–20 0–20 0–10 / 0–10 0–20 4–8 1 2–20 32–704
H43 1–43 0–43 0–21 / 0–21 0–43 8–16 1 2–43 32–1392
H66 1–66 0–66 0–33 / 0–33 0–66 12–24 1 2–66 32–2272
H89 1–89 0–89 0–44 / 0–44 0–89 16–32 1 2–89 32–3040
HA1 1–101 0–101 0–50 / 0–50 0–101 16–32 1 2–101 32–3040

Introduced in August 2012, the zEnterprise EC12 is based on the zEC12 chip, a 5.5 GHz 8-core out-of-order CISC-based zArchitecture processor. The zEC12 can have a maximum of 120 cores, 101 of which are customer configurable to run operating systems and applications.[28] The maximum number of cores available in a particular model of the zEC12 is denoted by the model name. For example, the H20 has up to 20 cores orderable for direct customer use, plus spare and a special I/O processor core type, the System Assist Processor. Each core can be characterized as a Central Processor (CP), Integrated Facility for Linux (IFL) processor, z Application Assist Processor (zAAP), z10 Integrated Information Processor (zIIP), Internal Coupling Facility (ICF) processor, or additional System Assist Processor (SAP). The zEnterprise EC12 allows up to 3 TB (usable) of redundant array of independent memory (RAIM).

The EC12 has 50% higher total capacity than the z196 (up to 78,000 MIPS), and supports Transactional Execution and Flash Express – integrated SSDs which improve paging and certain other I/O performance.

zEnterprise gen1 (114 and 196)

zEnterprise, announced in July 2010, with the z196 model, was designed to offer both mainframe and distributed server technologies in an integrated system. The zEnterprise System consists of three components:[29]

The zEnterprise is designed to extend mainframe capabilities – management efficiency, dynamic resource allocation, serviceability – to other systems and workloads running on AIX on POWER7, and Microsoft Windows or Linux on x86.[30]

The zEnterprise BladeCenter Extension (zBX) is an infrastructure component that hosts both general purpose IBM BladeCenter servers and appliance-like workload optimizers which can all be managed as if they were a single mainframe. The zBX supports a private high speed internal network that connects it to the central processing complex, which reduces the need for networking hardware and provides inherently high security.

The IBM zEnterprise Unified Resource Manager integrates the System z and zBX resources as a single virtualized system and provides unified and integrated management across the zEnterprise System. It can identify system bottlenecks or failures among disparate systems and if a failure occurs it can dynamically reallocate system resources to prevent or reduce application problems. The Unified Resource Manager provides energy monitoring and management, resource management, increased security, virtual networking, and information management from a single user interface.

zEnterprise 114 - The z114 is a entry-level single-rack solution, available in two hardware models: M05 and M10. Introduced in July, 2011, this system is designed to extend the benefits of the zEnterprise System to the mid-range business segment. Like the z196, the z114 is fully compatible with the zBX and the URM and also features the mission-critical server design elements. The z114 features up to 14 cores (up to 10 configurable) with a clock speed of 3.8 GHz. The z114 is physically approximately half the size of the z196.

z114 models
Model CPs IFLs zAAPs / zIIPs ICFs SAPs Spares zBX Memory (GB)
M05 0–5 0–5 0–2 / 0–2 0–5 2–4 0 0–1 8–120
M10 0–5 0–10 0–5 / 0–5 0–10 2–4 2 0–1 16–248

This model can contains up to 14 z196 out-of-order CISC-based zArchitecture processors running at 3.8 GHz. The z114 offers 130 capacity settings across two models and is designed to offer the hybrid capabilities of the zEnterprise System with a lower capacity, a lower energy usage, and lower price.[31] Each core can be characterized as a Central Processor (CP), Integrated Facility for Linux (IFL) processor, z Application Assist Processor (zAAP), z10 Integrated Information Processor (zIIP), Internal Coupling Facility (ICF) processor, or additional System Assist Processor (SAP). The z114 supports up to 248 GB (usable) of redundant array of independent memory (RAIM).

zEnterprise 196 - The z196 is a high-end dual-rack solution, and available in five hardware models: M15, M32, M49, M66 and M80. The model number is based on the number of cores available for customer workloads.[32] Additional cores are reserved as spares and as SAPs.

z196 models
Model CPs IFLs zAAPs / zIIPs ICFs SAPs Spares zBX Memory (GB)
M15 0–15 0–15 0–7 / 0–7 0–15 3 2–15 0–1 32–752
M32 0–32 0–32 0–16 / 0–16 0–16 6 2–32 0–1 32–1520
M49 0–49 0–49 0–24 / 0–24 0–16 9 2–49 0–1 32–2288
M66 0–66 0–66 0–33 / 0–33 0–16 12 2–66 0–1 32–3056
M80 0–80 0–80 0–40 / 0–40 0–16 14 2–80 0–1 32–3056

The 196's microprocessor is the z196 chip, a 5.2 GHz quad-core out-of-order CISC-based z/Architecture processor. The z196 can have a maximum of 24 processors giving a total of 96 cores, 80 of which are directly available to run operating systems and applications.[33] The number of cores available in a particular model of the z196 is denoted by the model name. For example, the M15 has 15 cores available for direct customer use, plus spare and service processor cores. Each core can be characterized as a Central Processor (CP), Integrated Facility for Linux (IFL) processor, z Application Assist Processor (zAAP), z10 Integrated Information Processor (zIIP), Internal Coupling Facility (ICF) processor, or additional System Assist Processor (SAP). The zEnterprise also supports x86 or Power ISA blades attached via the zEnterprise BladeCenter Extension (zBX). The zEnterprise 196 allows up to 3 TB (usable) of redundant array of independent memory (RAIM).

The zEnterprise z196 has twice the memory capacity of the z10, and 60% higher total capacity than the z10 (up to 52,000 MIPS). It supports the BladeCenter Extension (zBX) and Unified Resource Manager.

IBM System z10

Main article: IBM System z10

IBM System z10
IBM System z10

This generation of Z servers supported more memory than previous generation systems and can have up to 64 central processors (CPs) per frame. The full speed z10 processor's uniprocessor performance was up to 62% faster than that of the z9 server, according to IBM's z10 announcement, and included these other features:

Specific models from this family include:

IBM System z9

IBM System z9
IBM System z9

Main article: IBM System z9

In July 2005, IBM announced a new family of servers – the System z9 family – with the IBM System z9 Enterprise Class (z9 EC) and the IBM System z9 Business Class (z9 BC) servers. The System z9 servers offered:

Specific models from this family include:

IBM zSeries family

An IBM zSeries 800 (foreground, left) running Linux
An IBM zSeries 800 (foreground, left) running Linux

The eServer zSeries family, which includes the z900, z800, z990 and z890, introduced IBM's newly designed 64-bit z/Architecture to the mainframe world. The new servers provide more than four times the performance of previous models. In its 64-bit mode the new CPU is freed from the 31-bit addressing constraints of its predecessors. Major features of the eServer zSeries family:

Specific models from this family included:

Features

Processors and memory

The IBM zSeries systems were based on the z/Architecture chips - the out-of-order CISC-based zArchitecture multi-core processors. The maximum number of cores available in a particular model of the zEC12 is denoted by the model name. For example, the H20 has up to 20 cores orderable for direct customer use, plus spare and a special I/O processor core type, the System Assist Processor. Each core can be characterized as a Central Processor (CP), Integrated Facility for Linux (IFL) processor, z Application Assist Processor (zAAP), z10 Integrated Information Processor (zIIP), Internal Coupling Facility (ICF) processor, or additional System Assist Processor (SAP).

Processor book

A processor book is a modular card in IBM mainframes that contains processors, memory, and I/O connections.[35][36] A multi-chip module is welded onto each processor book for the z196 model.[37]

The computing power ordering

The typical ordering process of modern IBM Z mainframe looks like a buying of service[38] or looks like a leasing;[39] the mainframe is a program/hardware complex with rent for a system workload, and (in the most cases) additional system capabilities can be unlocked after additional payment.

Operating systems

The z15, z14, z13, zEC12, zBC12, z114 and z196 support the IBM operating systems: z/OS, z/VM, z/VSE, and z/TPF. Other operating systems available include Linux on IBM Z, such as Red Hat Enterprise Linux 6 and SUSE Linux Enterprise Server 11.[40] In November, 2011, IBM introduced Microsoft Windows Server 2008 support via x86 processor-based blades that plug into IBM's zEnterprise BladeCenter Extension (zBX). The zBX also supports the IBM WebSphere DataPower Integrated Appliance XI50 for zEnterprise (DataPower XI50z).

BladeCenter Extension (zBX)

zBX extension
zBX extension

The zEnterprise System supports an optional zEnterprise BladeCenter Extension (zBX). This add-on infrastructure supports redundant top-of-Rack switches, redundant power supplies, extra blowers, and IBM BladeCenter chassis. This add-on chassis allows POWER7 and x86 blade servers to be integrated with and managed from the mainframe.[41] A gameframe installation at Hoplon Infotainment is an example of a hybrid mainframe.

The zBX supports up to 112 blade modules.[42] The zBX and the System Z server are connected by a redundant, secure 10 Gigabit Ethernet connection, providing a private data network. There is also a 1 Gigabit Ethernet connection for management.

Unified Resource Manager

The zEnterprise Unified Resource Manager (zManager) allows the supported zBX platforms to be virtualized into a single system for management. It also allows for the prioritization of certain workloads in the system. The Resource Manager can monitor the various platforms for signs of bottlenecks or faults and modify the overall system to recover, maintaining a specified quality of service level.[43]

Liquid cooling

The zEC12 and z196 support external liquid cooling. Customers have the option of purchasing their mainframe with a water-cooled heat exchanger.[44]

PU characterization

Each purchased PU (processor unit) is characterized as one of a variety of types:

Also it's possible to run a zAAP-eligible workload on zIIPs if no zAAPs are enabled. IBM does not impose any software charges on work that is dispatched on zAAP and zIIP processors.

The addition of IFLs, zAAPs, zIIPs, ICFs, SAPs or IFPs does not change the system capacity setting or its MSU rating, only CPs do.

See also

References

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Further reading

IBM mainframes Preceded byIBM System/390 IBM Z 2000 - current IBM eServer zSeries IBM System z9 2005/2006 IBM System z102008 IBM zEnterprise IBM z132015/2016 IBM z142017/2018 IBM z152019/2020 z800, z9002000/2002 z890, z9902003/2004 z114, z1962010/2011 zBC12, zEC122012/2013