The Open Systems Adapter (OSA): Delivering ~25 Years IBM Mainframe IP Connectivity

Recently in my day-to-day activities I encountered a 3172 controller and was reminded of my first such encounter, back in 1992.  This got me thinking; 25 years of IBM Mainframe IP connectivity!  The IBM 3172 Interconnect Controller allowed LAN-to-Mainframe interconnection and was the pioneering technology allowing IP data off-load activities.  Historically Mainframe data transfer operations, namely CCW I/O were dependant on a physical channel, where the 3172 was a stepping stone to the Open Systems Adapter (OSA) card in 1994, quickly superseded by the OSA-2 card in 1995.  From a performance viewpoint, the OSA/OSA-2 cards matched maximum ESCON speeds of 17 MB/S.

However, the introduction of the OSA-Express technology in 1999 dramatically increased throughput to ~ 333 MB/S.  The OSA-Express technology bypasses CCW channel-based I/O processing, connecting directly to the Self-Timed Inter-connect (STI) bus of Generation 6 (Retrofit to Generation 5) S/390 Mainframes.  Data is transferred directly to or from the high speed Mainframe memory OSA-Express adapter I/O port, across the STI bus, with no intervening components or processing to slow down the data interchange.  This bus-based I/O, a first for IBM Mainframe computing, significantly increases data transfer speeds, eliminating inefficiencies associated with intermediary components.

Additionally, IBM developed a totally new I/O scheme for the OSA-Express adapter. Queued Direct I/O (QDIO) is a highly optimized data queuing-based data interchange mechanism, leveraging from the message queuing expertise IBM acquired with their multi-platform MQSeries middleware solution.  The QDIO-specific S/390 hardware instruction for G5/G6 machines, delivered an application to-OSA signalling scheme capable of handling the high-volume, multimedia data transfer requirements of 21st Century web applications.  Where might we be without the 3172 Interconnect Controller and the MQSeries messaging solution?

Since OSA-Express2 the channel types supported have largely remain unchanged:

  • OSD: Queued Direct I/O (QDIO), a highly efficient data transfer architecture, dramatically improving IP data transfer speed and efficiency.
  • OSE: Non-QDIO, sets the OSA-Express card to function in non-QDIO mode, bypassing all of the advanced QDIO functions.
  • OSC: OSA-ICC, available with IBM Mainframes supporting GbE, eliminating the requirement for an external console controller, simplifying HMC and to the z/OS system console access, while introducing TN3270E connectivity.
  • OSN: OSA for NCP, Open Systems Adapter for NCP, eradicates 3745/3746 Front End Processor Network Control Program (NCP) running under IBM Communication Controller for Linux (CCL) requirements.  Superseded by:
  • OSM: (OSA-Express for zManager), provides Intranode Management Network (INMN) connectivity from System z to zManager functions.
  • OSX: (OSA-Express for zBX), provides connectivity and access control to the IntraEnsemble Data Network (IEDN) to the Unified Resource Manager (URM) function.

Returning to my original observation, it’s sometimes hard to reconcile finding a ~25 year old 3172 Controller in a Data Centre environment, preparing for a z14 upgrade!  In conjunction with the z14 announcement, OSA-Express6S promised an Ethernet technology refresh for use in the PCIe I/O drawer and continues to be supported by the 16 GBps PCIe Gen3 host bus.  The 1000BASE-T Ethernet feature supporting copper connectivity, in addition to 10 Gigabit Ethernet (10 GbE) and Gigabit Ethernet (GbE) for single-mode and multi-mode fibre optic environments.  The OSA-Express6S 1000BASE-T feature will be the last generation to support 100 Mbps link speed connections.  Future OSA-Express 1000BASE-T features will only support 1 Gbps link speed operation.

Of course, OSA-Express technology exposes the IBM Z Mainframe to the same security challenges as any other server node on the IP network, and as well as talking about Pervasive Encryption with this customer, we also talked about the increased security features of the OSA-Express6S adapter:

  • OSA-ICC Support for Secure Sockets Layer: when configured as an integrated console controller CHPID type (OSC) on the z14, supports the configuration and enablement of secure connections using the Transport Layer Security (TLS) protocol versions 1.0, 1.1 and 1.2. Server-side authentication is supported using either a self-signed certificate or a customer supplied certificate, which can be signed by a customer-specified certificate authority.  The certificates used must have an RSA key length of 2048 bits, and must be signed by using SHA-256.  This function support negotiates a cipher suite of AES-128 for the session key.
  • Virtual Local Area Network (VLAN): takes advantage of the Institute of Electrical and Electronics Engineers (IEEE) 802.q standard for virtual bridged LANs. VLANs allow easier administration of logical groups of stations that communicate as though they were on the same LAN.  In the virtualized environment of the IBM Z server, TCP/IP stacks can exist, potentially sharing OSA-Express features.  VLAN provides a greater degree of isolation by allowing contact with a server from only the set of stations that comprise the VLAN.
  • QDIO Data Connection Isolation: provides a mechanism for security regulatory compliance (E.g. HIPPA) for network isolation between the instances that share physical network connectivity, as per installation defined security zone boundaries. A mechanism to isolate a QDIO data connection on an OSA port, by forcing traffic to flow to the external network.  This feature safeguards that all communication flows only between an operating system and the external network.  This feature is provided with a granularity of implementation flexibility for both the z/VM and z/OS operating systems.

As always, the single-footprint capability of an IBM Z server must be considered. From a base architectural OSA design viewpoint, OSA supports 640 TCP/IP stacks or connections per dedicated CHPID, or 640 total stacks across multiple LPARs using a shared or spanned CHPID.  Obviously this allows the IBM Mainframe user to support more Linux images.  Of course, this is a very important consideration when considering the latest z13 and z14 servers for Distributed Systems workload consolidation.

In conclusion, never under estimate the value of the OSA-Express adapter in your organization and its role in transitioning the IBM Mainframe from a closed proprietary environment in the early 1990’s, to just another node on the IP network, from the mid-1990’s to the present day.  As per any other major technology for the IBM Z server, the OSA-Express adapter has evolved to provide the requisite capacity, performance, resilience and security attributes expected for an Enterprise Class workload.  Finally, let’s not lose sight of the technology commonality associated with OSA-Express and Crypto Express adapters; clearly, fundamental building blocks of Pervasive Encryption…

z/VM: The Most Flexible System z Operating System?

When considering IBM System z Operating Systems, typically z/OS is considered to be the flagship product, delivering best-of-breed features, including but not limited to, performance, reliability, availability, security, capacity, et al.  Therefore it easy to overlook the flexible virtualization capabilities of z/VM, delivering the architectural foundation for the increasingly attractive LinuxONE offering.  Quite simply, the fundamental strength of z/VM is an ability for hundreds if not thousands of virtual machines to share system resources with high levels of resource utilization.  The recent release of z/VM V6.4 provides even greater levels of scalability, security, resource optimization and efficiency to create opportunities for cost savings, while providing a robust foundation for cloud computing on z Systems servers.

Major technical highlights of z/VM 6.4 include:

  • Simultaneous MultiThreading (SMT) technology extends per-processor, core capacity growth beyond single-thread performance for Linux on z Systems running on an IBM Integrated Facility for Linux (IFL) specialty engine on a z13, z13s or LinuxONE server.
  • Enhanced Real & Guest Virtual Memory Support. The maximum amount of real storage supported by z/VM increases from 1 to 2 TB, whereas maximum supported virtual memory for a single guest remains at 1 TB.  Maintaining the virtual to real memory allocation, doubling the real memory used, results in doubling the active virtual memory that can be used effectively.  This virtual memory can be sourced from an increased number of virtual machines and/or larger virtual machines, delivering greater leverage of white space.
  • Surplus CPU Power Distribution Improvement. Virtual machines not utilizing all of their entitled CPU power, determined by their share setting, generate “surplus CPU power.”  This surplus CPU resource can be distributed to other virtual machines in proportion to their share settings, managed independently across virtual machines for each processor type, namely General Purpose (GP), zIIP, IFL, et al.
  • Guest Large Page Support. z/VM 6.4 now includes support for the Enhanced Dynamic Address Translation (DAT), allowing a guest machine to exploit large (1 MB) pages.  Larger page sizes decrease the amount of guest memory needed for DAT tables, therefore decreasing the overhead required to perform address translation.  In all cases, guest memory is mapped into 4 KB pages at the host level.

From a Linux environment viewpoint, z/VM V6.4 is a supported environment using IBM Dynamic Partition Manager for Linux-only systems with SCSI storage.  This simplifies system administration tasks for a more positive experience by those with limited System z Mainframe administration skills.  IBM Wave Version 1 Release 2 is now included in z/VM V6.4 as a priced feature, simplifying the task of administering a z/VM environment.  Using Dynamic Partition Manager, an inexperienced z/VM technician can create a z/VM partition in ~10 Minutes!

Supporting today’s agile application development and hybrid cloud implementations, z/VM and LinuxONE virtual servers can be natively managed using OpenStack open cloud architecture-based interfaces IBM OpenStack for z Systems.  OpenStack is an Infrastructure as-a Service (IaaS) cloud computing open source project, managed by the OpenStack Foundation.  With the adoption of OpenStack as part of the IBM cloud strategy, z/VM drivers provide OpenStack enablement for z/VM virtual machines running Linux on z Systems and LinuxONE.  Open standards such as OpenStack enable enterprises to be more agile, resolving potential issues such as vendor lock-in, technical expert recruitment, long application development cycles and security challenges.

The next evolution of z/VM cloud enablement technology is the OpenStack Liberty based Cloud Management Appliance (CMA), available for z/VM 6.3 and 6.4.  z/VM installations wanting to deploy cloud based solutions beyond Cloud Manager with OpenStack for z Systems, should utilize the cloud enablement support provided by the z/VM OpenStack Liberty based CMA.  This OpenStack Liberty based Cloud Management Appliance (CMA) replaces the IBM Cloud Manager with OpenStack for System z solution, withdrawn from marketing in June 2016.

The z/VM hypervisor extends the capabilities of z Systems and LinuxONE environments from the standpoint of sharing hardware assets, virtualization facilities and communication resources.  In conjunction with IBM Wave, z/VM makes it easier to derive maximum value from largescale virtual server hosting on z Systems and LinuxONE.  These benefits includes software and personnel savings, operational efficiency, power savings and optimal qualities of service.  The z/VM virtualization technology is designed to enable organizations to run hundreds to thousands of Linux servers on a single System z Mainframe footprint, alongside other System z Operating Systems, such as z/OS, z/VSE, or as a large-scale enterprise LinuxONE server solution.

Advanced virtualization features like multisystem virtualization and live guest relocation with z Systems, LinuxONE, z/VM, and Linux on z Systems or LinuxONE help to provide an efficient infrastructure for deploying private clouds to support workloads that scale both horizontally and vertically at a low total cost of ownership.

Although some might consider z/OS to be the flagship IBM system z Mainframe Operating System, arguably z/VM is the industry standard for optimal resource virtualization for numerous Operating System deployments.

System z Meets Open Source Linux

Recently IBM launched their LinuxONE offering, packaged in the most powerful and secure enterprise server, namely System z, designed for the new application economy and hybrid cloud era. Although IBM has provided Linux support for the Mainframe server since 2000, this LinuxONE packaging promises a unified portfolio of hardware, software and services solutions for mission-critical Linux applications.

To supplement the existing SUSE and Red Hat support, Ubuntu is included, along with Open Source enablement, including Apache Spark, Chef, Docker, MariaDB, MongoDB, Node.js and PostgreSQL, endeavouring to provide clients with choice and flexibility for hybrid cloud deployments.

From a big picture viewpoint, LinuxONE can be summarised as:

  • Linux Your Way: Choose the Linux environment and tools for your organization
  • Linux Without Limits: Benefit from Enterprise Class Linux support
  • Linux Without Risk: Safeguard business applications with the secure and resilient System z Server

The LinuxONE Systems are classified as Emperor and Rockhopper, loosely classified as High-End and Entry-Level System z servers. LinuxONE Emperor delivers ultimate flexibility, scalability, performance and security trust for mission-critical applications. Scalability is as per the latest z13 server, allowing growth to handle the most demanding workloads. LinuxONE Rockhopper delivers the entry point into the LinuxONE family, offering all the same great capabilities and value, with the flexibility of a smaller package.

LinuxONE includes a choice of hypervisors and management tools, namely KVM for LinuxONE and/or IBM z/VM. This virtualization capability claims support for up to 8000 virtual servers (several thousand containers) in a single System z server footprint, allowing for parallel processing of Test, Development and Production environments. Additionally, new servers and containers can be initialized and running in minutes, with automated resource provisioning and reallocation in seconds.

From a performance viewpoint, System z metrics apply; fast CPU processors, significant I/O capability and 10 TB Memory, all delivering consistent and predictable sub-second response times for thousands of users. A reported capability of 30 Billion RESTful web transaction per day, with ~500,000 database read/write operations per second.

The LinuxONE offering is also a key component of the IBM Cloud, Analytics, Mobile & Security (CAMS) framework:

  • Cloud: An agile and trusted cloud infrastructure to meet new business demands with greater efficiency and lower costs for IT service delivery. Example cloud usage includes Database, Enterprise Systems of Record and Hybrid Platform cloud platforms.
  • Analytics: Flexible, resilient, high performance business and operational analytics for Business Intelligence, Big Data Insights and Operational Analytics for intelligent and continuous business availability.
  • Mobile: Build a premier mobile solution for your business to deliver the best possible experience for your clients, employees and partners alike. Facilitate agile development and deployment of mobile applications, with secure end-to-end mobile transactions, personalized via integrated data analytics.
  • Security: System z has been associated with the highest EAL5+ Common Criteria certification for many years, safeguarding mission-critical data from cradle-to-grave. Security functions such as full data encryption, cryptographic processors and end-to-end security, combined with the unmatched reliability and availability of the System z server, safeguarding mission-critical data and services are fully protected and available.

Finally and a key point, LinuxONE promises TCO optimization with pricing your way. A straightforward menu of pricing options include:

  • A fixed monthly cost usage model for hardware and software resources
  • A per core software pricing model, with 30 days notice for cancellation or resource change
  • A 36 month rental option, with buy/replace/return options at contract end

In theory, LinuxONE could be perceived as just a tweak of existing System z Linux options, including the most recent z13 server, Ubuntu and Open Source support. What has changed are user requirements, the requirement for flexible and agile computing, where Cloud, Analytics, Mobile and Security dominate many CIO agendas.

It is my hope that each and every CIO, System z literate or not, at least considers the LinuxONE platform for their mission-critical enterprise workload, as from a simplistic viewpoint, LinuxONE is just another ubiquitous black server box; or is it…

IBM System z PartnerWorld Solution Development Evolution

Currently there are in excess of 2,300 companies delivering solutions for IBM System z listed in the IBM Global Solutions Directory. Considering the number of global System z customers, currently estimated as ~4,000, this is quite a good ratio! It’s also evidence of the significant ability of this System z ecosystem to deliver innovation and support to said customer base. Maybe we should consider how these System z solution delivery businesses develop and maintain their software, hardware and service offerings…

Obviously to develop, support and enhance an IBM Mainframe software or hardware product, access to an IBM Mainframe is a mandatory requirement. In the 1980’s, procuring an IBM Mainframe was an expensive undertaking, hence the number of IBM Mainframe IHV (Hardware) or ISV (Software) partners was limited. Therefore we should not overlook the evolution that has taken place in the last 25 years or so, delivering the significant, diverse, innovative and global System z ecosystem in place today.

In the early 1990’s the IBM Advanced Workstations Systems Division (AWS) worked on delivering complete compatibility with existing IBM Mainframe operating systems and software, delivering this function in the S/390 Processor Card. Later iterations of this S/390 Processor Card offered plug compatibility with RISC and PC server architectures, packaged as R/390 and P/390 servers respectively. In essence these R/390 and P/390 server solutions delivered “A Mainframe In A Box”. Put another way, the entire IBM Mainframe infrastructure including CPU, Memory, I/O Subsystem, Consoles, Disk, Tape, Networking Interfaces, et al, were all contained within the one PC or RISC based server footprint. Some of the software modules we might be familiar with for delivering this functionality are AWSDISK, AWSPRINT and AWSTAPE, where the respective function is denoted by the module name.

Therefore with the R/390 and P/390, subsequently followed by the S/390 Integrated Server and then MP3000, low cost access to IBM Mainframe servers was possible. However, let’s not forget that in conjunction with hardware compatibility, low cost access to existing IBM Mainframe operating systems and software was also required. This software access was delivered by the Application Developers Controlled Distributions (ADCD), incorporating a package of the majority of IBM Operating System and supporting subsystem program products. Therefore, once a business proved its intentions in developing a software or hardware solution for the IBM Mainframe, they gained very low cost access to said IBM Mainframe software. Without doubt, the innovation of the S/390 Processor Card and Application Developers Controlled Distributions (ADCD) resources, allows the System z community to benefit from the related ecosystem in place today.

This IBM Mainframe emulation capability provided the opportunity for other 3rd party supplier to deliver x86 servers that supported the IBM PartnerWorld for Developers (PWD) ADCD initiative. For example, FLEX-ES from Fundamental Software.

Currently, IBM deliver the System z Personal Development Tool (zPDT) for ADCD access, while many ISV’s and IHV’s now actually deploy an official IBM System z server, for example, zBC12, as the cost of Mainframe servers has reduced substantially in the last decade or so. Optionally, recognizing the virtualization capabilities of System z and higher speed network access, System z development can now be achieved remotely. The System z Remote Development Program (zRDP) for z/OS, z/VM and z/VSE provides qualified partners with remote access to supported generally available and supported operating systems and software products. Additionally, IBM has built a number of Innovation centres globally (I.E. Africa & Middle East, Asia Pacific, Europe, Latin America, North America), facilitating the possibility for System z innovation with local resources.

An example of the diversity and innovation of the System z ecosystem is the SVA zHosting concept, allowing an IBM PartnerWorld for Developers (PWD) member and/or Independent Software Vendor (ISV) the ability to port existing or install new development environments into a local fully certified IBM System z Mainframe data centre, in this case, located in Germany.

In conclusion, as other IT technologies have evolved, IBM have provided a cost-efficient environment, encouraging and maintaining the IBM System z Mainframe ecosystem. Firstly in the 1990’s with full emulation for RISC and PC based servers and more latterly in the 21st Century with remote access. This low cost access to full System z capability, safeguards that the System z ecosystem remains significant, current, diverse, while the realm of possibility for innovation exists.

z13: A Digital Business Ready Solution?

As per the usual next generation zSeries Server release, IBM announced their latest evolution on 13 January 2015, namely the z13. IBM describe this platform as the most powerful and secure system ever built:

  • First system able to process 2.5 billion transactions per day, built for mobile economy
  • Makes possible real-time encryption on all mobile transactions at scale
  • First mainframe system with embedded analytics providing real time transaction insights 17X faster than compared competitive systems at a fraction of the cost

At first glance, feeds and speeds generally don’t enthuse the audience, but if we dig deeper and acknowledge other recent IBM developments incorporating Apple, Twitter and Data Analytics announcements, we perhaps can draw some better business-facing conclusions. IBM have a clearly defined Cloud, Analytics, Mobile, Social & Security (CAMSS) initiative, seemingly based upon the IDC 3rd platform defined as Social, Mobile, Analytics & Cloud (SMAC).

Industry analysts predict that in the next 3 years and by 2017, SMAC (CAMSS) expenditure will account for 25%+ of total enterprise software market revenue, doubling from ~12% in 2012. In simple terms, this new expenditure opportunity represents $100+ Billion revenue. We can imagine that all major ISV’s will be wanting their share of this market…

Whichever classification you choose, IBM CAMSS or IDC SMAC, IT infrastructures and associated investment currently are and certainly will be heavily influenced by this new world computing paradigm. Like it or not, an ability to perform a transaction anywhere (Mobile), keeping everything simple and networked (Social Media), real time prediction of future customer requirements (Analytics), available anywhere (Mobile), for an alleged fraction of the cost (Cloud), makes sense for the 21st Century business. Ignore this new technology evolution at your peril as it will impact each and every area of the IT enterprise and associated resources, primarily software and supporting hardware.

Did you notice the difference between the IBM classification and IDC? IDC have not considered Security to be a consideration factor worthy of acronym (SMAC) inclusion. In today’s world of cybersecurity, that might be somewhat of an oversight, but we must assume that IDC consider cybersecurity to be a consideration for all of the Analytics, Cloud, Mobile & Social aspects, which of course it is!

If we consider the relative merits of technology platforms from a security viewpoint, the IBM z13 delivers EAL5+ security certification, whereas other non-Mainframe platforms can only currently claim EAL4+ certification.

It is estimated that 55%+ of enterprise (mission critical) transactions are processed by the IBM Mainframe, but this is based on pre mobile workloads. It therefore makes commercial sense for IBM to safeguard their flagship platform not only maintains the existing IBM Mainframe customer base, but captures new and mobile centric workloads.

Having considered the business requirements for today’s IT business, let’s now classify the new features of the z13 platform:

  • Up to 40% more total system capacity compared to the zEC12.
  • Up to 10 terabytes (TB) of available Redundant Array of Independent Memory (RAIM) real memory per server.
  • Cryptographic performance improvements with new Crypto Express5S.
  • Economies of scale with simultaneous multithreading delivering more throughput for Linux and zIIP-eligible workloads.
  • Improved performance of complex mathematical models, perfect for analytics processing, with Single Instruction Multiple Data (SIMD).
  • IBM zAware cutting-edge pattern recognition analytics for fast insight into system health extended to Linux on z Systems.
  • A reduction in elapsed time for I/O-bound batch jobs with new FICON Express16S versus FICON Express8S.
  • Support for larger memory configurations planned to be supported on z/OS systems, which can be used to improve transaction response times, lower CPU costs, simplify capacity planning and ease deploying memory-intensive workloads. (The IBM z13 offers up to 10 TB memory.)
  • I/O service time improvement when writing data remotely using the new zHPF Extended Distance II.
  • Support for up to 256 coupling CHPIDs, which provides enhanced connectivity and scalability for a growing number of coupling channel types.
  • IBM Integrated Coupling Adapter (ICA SR), which offers greater short reach coupling connectivity than existing link technologies and enables greater overall coupling connectivity per IBM z13 than prior server generations.
  • Capability to extend z/OS workload management policies into the SAN fabric.
  • New rack-mounted Hardware Management Console (HMC), helping to save space in the data center.
  • Non-raised floor option, offering flexible possibilities for the data center.
  • Optional water cooling, providing the ability to cool systems with user-chilled water.
  • Optional high-voltage dc power, which can help IBM z Systems clients save on their power bills.
  • Optional top exit power and I/O cabling designed to provide increased flexibility.
  • New IBM z BladeCenter Extension (zBX) Model 004 in support of heterogeneous resources managed by IBM z Unified Resource Manager.

As we all know, Moore’s Law had to end sometime soon and this is true for System z CPU chips. The zEC12 CPU was often claimed to be the fastest commercial processor, with a 32nm core and a 5.5 GHz rating. The z13 chip runs a 22 nm core at a 5 GHz, at first glance ~10% slower than the zEC12. The new z13 chip delivers a ~10% performance increase, due to advances in core design, with better branch prediction and pipelining in the core. Noteworthy, is the slightly slower clock speed of the z13 chip, reducing heat output, probably signifying that ~5 GHz is the ceiling for CPU chips in the near future.

However, for z13, the doubling of performance still apples for many other resources:

  • Cryptographic coprocessors performance (~2*)
  • Channel speed (~2*)
  • I/O bandwidth (~2*)
  • Memory/Cache performance (~2*)
  • Memory capacity (~3*)

Once again, classifying these technological advances in terms of mobile business, the z13 delivers real-time encryption of mobile transactions, protecting transaction data, delivering consistent response times for a quality customer experience. Overall, IBM claims the z13 delivers a potential for ~36% better response time, ~61% better throughput and ~17% lower cost per mobile transaction.

A major and subtle change introduced with the z13 is Simultaneous MultiThreading (SMT). SMT allows 2 active instruction streams per core, each dynamically sharing the core’s execution resources. SMT will be available in IBM z13 for workloads running on the Integrated Facility for Linux (IFL) and the IBM z Integrated Information Processor (zIIP).

Each software Operating System/Hypervisor has the ability to intelligently drive SMT in a way that is best for its unique requirements. z/OS SMT management consistently drives the cores to high thread density, in an effort to reduce SMT variability and deliver repeatable performance across varying CPU utilization, thus providing more predictable SMT capacity. z/VM SMT management optimizes throughput by spreading a workload over the available cores until it demands the additional SMT capacity.

From a capacity planning and performance measurement viewpoint, just a slight note of caution. Although the z13 CPU chip delivers increased CPU capacity, the raw speed is slower and there are considerations for SMT. A former IBM staffer, Bob Rogers has written a great article on this SMT subject matter, which should be on your reading list!

In conclusion, the z13 announcement is another step forward for zSeries Mainframes. If you consider this announcement as just another next generation zSeries Mainframe announcement, you’re not treating your business or yourself with the respect they deserve. Instead, please consider this z13 announcement as an evolution from an enterprise solution delivery viewpoint. Primarily, consider the 21st century business keywords, in no particular order, of Analytics, Cloud, Mobile, Social & Security.

IFL – A Cost Efficient zSeries Platform?

In September 2000, IBM introduced the Integrated Facility for Linux (IFL) processor, a specialty engine for and some might say dedicated to running the Linux Operating System.  At the time of this announcement, companion software named S/390 Virtual Image Facility for Linux was introduced to assist in the rapid deployment of IFL configurations, especially for non-Mainframe personnel.  However, this product was quickly discontinued, in favour of the standard z/VM Operating System, which is not difficult to learn and can accommodate hundreds if not thousands of zLinux images.

Today, the IFL is still a processor dedicated to Linux workloads on IBM System z servers.  The IFL is supported by z/VM virtualization and the Linux operating system.  The IFL cannot run other IBM operating systems.  The competitively priced IFL processor is a CPU capacity enabler, exclusively for Linux workloads.  Linux deployment (I.E. SUSE & Red Hat) on IFL’s can reduce expenses in the areas of operational efforts, energy, floor space and especially software.

The IFL provides the following functions and benefits:

  • The IBM Enterprise Linux Server is a dedicated System z Linux server, comprised of only IFL processors
  • No additional IBM software charges for traditional (E.g. z/OS, CICS, DB2, WebSphere, et al) environment
  • Performance improvement for Linux workloads with each successive generation of IFL and System z technology
  • Linux workload on the IFL does not result in increased IBM software charges for traditional System z operating systems and middleware
  • Same functionality as a General Purpose processor on a System z server
  • HiperSockets can be used for communication between Linux images, or Linux and other operating system images on the same System z system
  • z/VM virtualization and most IBM Linux middleware products, plus most vendor software products are priced per processor (core) according to the System z IBM International Program License Agreement (IPLA).  IPLA products have a one-time-charge (OTC) and an annual (optional) maintenance charge, called Subscription & Support
  • Supported by the current z/VM virtualization and IBM Wave for z/VM software versions
  • Always a full capacity processor, independent of the capacity of the other processors in the server
  • Orderable as a System z hardware feature. The number of orderable IFL features varies by the server model and configuration
  • Designed to operate asynchronously with other General Purpose processors
  • Managed by PR/SM in logical partition with dedicated or shared processors. The implementation of an IFL requires a Logical Partition (LPAR) definition, where following normal LPAR activation procedure, LPAR defined with an IFL cannot be shared with a general purpose processor.

There will always be the debate as to which processor and associated server type (E.g. x86, POWER, SPARC) is the most cost efficient, but there is no doubt that the ability to accommodate hundreds if not thousands of zLinux instances in one zServer environmental (E.g. Power, Cooling, Floor Space, et al) friendly footprint, with software pricing per core is worthy of consideration.

Adoption for zLinux has been steady and especially in the emerging territories where it’s not unusual for zSeries deployments to be totally zLinux (I.E. IBM Enterprise Linux Server) based.  Moreover, the majority of large and traditional IBM Mainframe users (I.E. z/OS) have installed at least one IFL, if only to evaluate the z/VM and zLinux offering.  Many have deployed the IFL and associated zLinux solution for business requirements.

Therefore, if one of the major cost benefit features of IFL is optimized software costs; can the IFL processor be considered for other workloads, originating from the traditional zSeries (I.E. z/OS) environments?

Proximal Systems Corporation (PSC) is a company with a solution that transparently offloads data processing from IBM Mainframes to Distributed Systems, with an objective of reducing software cost, while maintaining or improving performance.  The company name is derived from the concept of bringing disparate computing systems into close proximity, functionally speaking, providing totally seamless and transparent interoperability.  The result is a unified computing complex within which various tasks can be easily migrated between systems to their most cost efficient operating environment, while still being able to interoperate as if they were all hosted together on the same system.

The PSC Proxy Coupling Technology allows for a CPU orientated task to be offloaded from one system to another by means of an associated proxy task, which has an identical interface as the task to be offloaded, but delegates the majority of the processing to an offloaded task on another system.  The primary objective of this function are for the cost savings and/or performance improvements that might be delivered by migrating tasks to systems that are able to execute those tasks more efficiently.

The fact that the proxy task maintains the same interface as the application being replaced is crucial; as many past Mainframe migration projects have failed due to insurmountable interoperability problems between the Mainframe and Distributed Systems servers (I.E. Windows, Linux, UNIX, et al).  Proxy Coupling Technology offers a solution to this long-standing challenge.  In theory, this allows for the transparent offload of a traditional z/OS workload (E.g. Sort) from General Purpose (GP) processors, to a less expensive (E.g. IFL) alternative…

In the first instance, the Proxy Coupling Technology offloads General Purpose CPU workload associated with the z/OS sort (I.E. CA Sort, DFSORT, Syncsort) function, to another platform (E.g. IFL).  For IFL based implementations, HyperScokets are utilized to transfer data at memory speeds from the z/OS task to zLinux on the IFL, where the sort operation completes, while the resulting z/OS task and associated data are maintained, as per normal.  From an IFL viewpoint, Ahlsort software performs the sort operation, being a sort solution that maintains compatibility with the majority of z/OS sort function (I.E. Control Card Syntax).  Therefore, this is a transparent implementation, where the only consideration is how much CPU capacity is required for the offload function (E.g. IFL, x86).  The benefits are reduced z/OS MSU usage for the sort function, which can be quite significant, as most business data (E.g. Database Offloads, Customer Orientated, et al) is sorted on a daily if not more frequent basis.

Just as IBM introduced the zAAP on zIIP capability, which allowed some customers to more easily justify a specialty engine (I.E. zIIP), combining workloads to exploit the full capability of the specialty engine; in theory the same ethos applies with the Proxy Coupling Technology.  For the avoidance of doubt, workloads that can be processed on an IFL, such as z/OS sort tasks, can assist in delivering higher Return On Investment (ROI) levels for the IFL, for example:

  • Reduced z/OS WLC MSU usage (I.E. Sort function offload) and associated software costs savings
  • IFL processors run at Full Speed and do not add to traditional workload (I.E. z/OS) software costs
  • Utilize any spare IFL CPU resource not used, releasing General Purpose CPU resource for other work

In conclusion, the Proxy Coupling Technology offers a proposition that is similar to the IBM philosophy of reducing z/OS software costs via specialty engines.  Seemingly to date, primarily only the zIIP and zAAP specialty engines were available to optimize CPU usage for z/OS workloads.  Offloading CPU cycles and thus MSU workload to IFL makes sense, utilizing a cost efficient and indeed a full power CPU engine, where for cost reasons, maybe the majority of z/OS customers don’t deploy the “highest” derivative of General Purpose CPU engine available to them.  On the face of it, the realm of possibility exists for other workloads to benefit from z/OS to IFL CPU offload, following sort, which seems to make sense as the first workload to utilize this solution.