Novell’s Markus Rex – celebrating 10 years of Linux on the mainframe

SUSE Linux Enterprise Server for System z boasts intelligent CPU and memory balancing capabilities so that a ‘pool’ of CPU resources can be directed dynamically to a Linux guest. How effectively does this increase uptime and availability of the Linux guest and the provided applications?
Uptime is not the issue – it’s more about how efficiently you can use hardware resources related to your workload. With z/VM you can define resources from specific VM guests. You can have more of these if you overcommit memory and CPU: this drives the consolidation ratio and thus workload costs down. But if you expect temporary peeks, which may exceed a single CPU’s capacity, you can configure the system to respond ‘policy driven’ to that demand – and return to the previous state later. Or use this to keep service response times reasonable.

The overwhelming majority of Linux mainframe customers use IBM mainframes. Given the company’s crucial role in mainframe Linux evolution, what period of the last decade’s developments stand out to you as strategic inflexion points in the total development curve?
A few standouts: starting with adapting the relevant parts of the Linux kernel and GNU tool chain to facilitate the port, then providing a commitment to invest in Linux and open source. Followed by establishing joint processes with SUSE/Novell for development and support, later on maintaining 31-bit compatibility for ISVs while introducing a 64-bit system. Also, leveraging mainframe virtualisation technologies to move more workloads to the mainframe even before the hype of x86 hypervisors. Then in the last years, integrating hot-add and dynamic resource interaction to Linux while bumping up single machine workload capacity.

Back in 2000, a two-week install party was held for SUSE Linux Enterprise Server where customers were taken through the first installation steps by conference call. What elements of the fully evolved installation process today represent the most groundbreaking or innovative steps?
We went from text-based to graphical install. In the past, we did something similar to a remote install: boot (load) the installation system, interact with the console, establish a network connection and then proceed. Something comparable to PXE boot, I suppose. Today, we have support from the mainframe management console to boot from SCSI DVD and more usable terminals. We can do automated installations with AutoYaST and, once you have a golden image, cloning is the preferred way to provision systems. With the I/O power of the mainframe, its a matter of seconds.

IBM developed the Integrated Facility for Linux (IFL) speciality processor dedicated to running the Linux operating system way back in 2000. Since that time, how has enterprise Linux developed to take advantage of the specific architecture of the IFL?
IBM and Novell have worked very closely over the past ten years to look for ways to exploit all of the benefits of the mainframe; not just the IFL. Compiler advances, CPU affinity, memory management and I/O improvements are all ingredients that make the mainframe a highly reliable system for customers’ most
demanding workloads.

Red Hat has worked hard to try and develop its RHEL releases cycles in a way that gives it the maximum opportunity to gain proximity (and therefore arguably market penetration) into your customer base. How successful has your competitor been in this regard and what metrics can you share with us to state your current overall position in the market?
Success in this market isn’t very dependent on the release cycle. What’s worked for us has been synchronising SUSE Linux Enterprise Server development with mainframe platform innovation, which has enabled us to forge an enduring partnership with IBM. As the mainframe architecture has evolved, SUSE Linux Enterprise Server has consistently been the first distribution to exploit the new capabilities like memory or CPU hotplug. We co-operate closely with IBM to implement customer-requested enhancements in a very timely manner. Also, our development departments – the IBM Labs in Böblingen and the SUSE development team in Nuremberg – share a long history and a deep friendship. Although other enterprise Linux offerings have entered the market, Novell with SUSE Linux Enterprise Server for System z clearly dominates the Linux mainframe market, with more than 80 per cent market share today.

Tell us about your pricing strategy and how you have worked with IBM to bring costs down to ease the marriage of Linux on the mainframe.
Our pricing strategy is also tightly aligned with IBM´s product development and product positioning strategy for its mainframe technology. For example, IBM introduced the Integrated Facility for Linux, a special mainframe processor tailored for running Linux workloads, better known under IFL. The IFL was mainly introduced to allow users to run Linux operating systems and applications on the mainframe at reduced costs. Shortly after IBM introduced IFL, Novell implemented its pricing for SUSE Linux Enterprise Server on a subscription per IFL basis. Recently we extended our subscription model for SUSE Linux Enterprise Server for System z; now called ‘Multi-IFL’, which offers volume discounts for orders of multiple IFL subscriptions.
In addition to our permanent Multi-IFL pricing, we team up with IBM around special offerings. Whenever IBM plans a special campaign or offering around its mainframe offerings, customers can be sure to find a compelling Linux promotion offering from Novell that complements the IBM offering. The most recent example is a promotion offering SUSE Linux Enterprise Consolidation Suite for System z, which aligned with IBM’s new System z Solution Edition for Enterprise Linux Server offering. The Novell promotion not only provides a very attractive initial subscription price for the Linux operating system with a low TCA, but also comes with additional benefits such as training or the possibility to consolidate .NET workloads to System z
using Mono.

Given the exponential progression path that Linux has taken over the last decade, do you think there will be something of a levelling out over the next ten years – and if so, will this positively or negatively affect how Linux is regarded?
Absolutely not! Linux continues to grow beyond its expectations in new ways that have yet to be considered. We expect to see growth in high-performance computing and enterprise computing markets. We’re also seeing significant adoption among communication devices, entertainment devices, home appliances – any network-aware device.  Manufactures are embedding Linux into all aspects of our lives to create intelligent systems for our homes, cities and infrastructure.

Click here to see what else featured in issue 87 of Linux User & Developer magazine…