WELCOME to the second issue of CMG Journal for 2017. As summer in the northern hemisphere is upon us, what better way to beat the heat and thunderstorms than grab a nice cool beverage, sit down, relax, and read the four papers in this great issue. For those CMGers in the southern hemisphere getting ready to endure winter, grab a hot chocolate, relax by the fireplace and do the same thing.

Our first paper was written by Scott Chapman of Enterprise Performance Strategies. z/OS SMT Measurements: Investigation and Explanation discusses IBM’s introduction of Simultaneous Multithreading (SMT) for z13 zIIP and IFL engines. IBM did this to help address a common issue across the computer industry: it’s getting difficult or impossible to make CPUs faster by simply adjusting clock speed and implementing features that were pioneered decades ago in the bipolar days. SMT attempts to address this by allowing a single CPU core to work on two different execution threads simultaneously. Read Scott’s outstanding paper to learn the details.

Our second paper, Capacity Planning Revisited written by Terry Critchley, discusses the three main issues Terry sees in performance today:

  • sizing in the design of a system intended to provide a business service to a service level agreed with the business (SLA)
  • performance management; ongoing and other management aspects of that system
  • capacity planning or ‘how will we perform in the future against our baseline’ and ‘will it meet the changing business requirements’?

Our third paper, was written by Girish Gundale and Rajan Lahiry. Performance Testing-Payments
Engine discusses the challenges in performance testing programs which are migrating from
mainframes to a heterogeneous middleware stack and explains the performance test methodology,
implementation strategy & best practices to be followed taking mass & direct debit/credit payment
engines as examples which are the prime candidate for these transformation programs.

Our fourth paper, Understanding the Technology and Performance Implications of FICON
Dynamic Routing is mainframe centric and was written by David Lytle and Steve Guendert. As
part of the z13 announcement in January 2015, IBM announced support for a new FICON routing
technique for FICON interswitch links (ISLs) called FICON Dynamic Routing (FIDR). This paper
explains how the predecessor technology (static routing) works, compares it with the new FICON
Dynamic Routing mechanism, and concludes with a discussion of the possible use cases where
implementing FICON Dynamic Routing will be of the most benefit to z Systems end users.

We are actively soliciting papers for future issues of CMG Journal. We are planning on publishing
four issues per year, with a goal of four to five high quality papers per issue. Our next issue is planned
for September 2017 and we are currently reviewing submissions. Please consider writing a paper for
the CMG Journal. You can submit your papers, as well as feedback to us at cmgjournal@cmg.org.

Thanks again for reading, and we hope you enjoy this issue.

Stephen R. Guendert, Ph.D, CMG Journal Editor