Greetings! I recently returned from a 3 week long around the world business trip to Brazil and Australia. I had a wonderful time meeting with many of our valued customers and OEM partners and would like to publicly thank them for their tremendous hospitality. I also would like to thank my Brazilian and Australian Brocade colleagues for their wonderful hospitality. In the rest of today's blog post I would like to talk about the zEC12, DCX 8510, cars and tires.
On 28 August 2012 IBM announced the zEnterprise EC12 (aka zEC12). For those of you who have read the full IBM announcement you're well aware that it is quite an impressive machine in terms of performance, scalability, and management. I'd like to focus on the channel subsystem enhancements introduced with the zEC12. They all deal with a topic very important to many of you (and near and dear to yours truly) and that is performance of the FICON environment.
IBM has enhanced the I/O subsystem of the zEC12 to provide improved throughput and I/O service times when abnormal conditions occur. These abnormal conditions include multi-system resource contention in the storage area network (SAN) or at the control unit ports, SAN congestion, improperly defined SAN configurations, dynamic changes in fabric routing, firmware failures, hardware failures (such as link speeds not initializing correctly), cabling errors, and destination port congestion. When these abnormal conditions occur they can cause an imbalance in I/O performance characteristics (such as latency and throughput) across a set of channel paths to the control unit. The zEC12 channel subsystem is designed to intelligently utilize the channels that provide optimal performance. This enhancement is accomplished by exploiting the in-band I/O instrumentation and metrics of the System z FICON and System z High Performance FICON (zHPF) protocols and new intelligent algorithms in the channel subsystem designed to exploit this information. When conditions occur that cause an imbalance in performance (I/O latency/throughput) the channel subsystem will bias the path selection away from poorer performing paths toward the well performing paths. This channel subsystem enhancement is exclusive to zEC12, is supported on all FICON channels when configured as CHPID type FC, and is transparent to the operating system. To coincide with these enhancements, IBM introduced an enhancement to the RMF Direct Access Device Activity report. This enhancement is Average Interrupt Delay Time (AVG INT DLY). The average interrupt delay time is measured in units of milliseconds encountered for I/O requests to a device. For each I/O request, the time is measured from when a subchannel is made status pending with primary status to when the status is cleared by TSCH and executed in the operating system.
To unleash the full power and capabilities of the new zEC12, IBM announced qualified support for Brocade DCX and DCX 8510 Backbones, 5100 and 5300 switches and Brocade 7800/FX8-24 extension platforms at General Availability (GA) of the zEC12. As previously announced in IBM and Brocade Statements of Direction, ESCON channels and legacy SAN platforms, including the Brocade M6140 and Mi10K directors and USD-X and Edge 3000 extension devices, are not qualified or supported on the new zEC12. A brief analogy will help explain why. Some of you whom I have met with recently have heard Steve's tire analogy before so please bear with me.
At one point yours truly was the "proud" owner of a 1995 Chevy Cavalier. That was a step up from the 1984 dark brown Plymouth Horizon I had driven earlier in my life. One thing the two cars had in common besides the lawn mower engine were tires with track width the size of bicycle tires. Which was fine for those cars, as performance and high speed cornering were not what they were made for.
Now, let's say I wanted to upgrade that 1995 Cavalier to a2012 Chevy Corvette ZR1 , which is a high performance super car. Comparing the performance of a Chevy Corvette to that 1995 Cavalier is like comparing the I/O performance of a new IBM zEC12 to an IBM z900. However, suppose that to save some money, I decided that rather than pay the extra money for the Michelin Pilot Sport Cup tires, I simply would keep the tires from my Cavalier and move them to the Corvette. Guess what happens the first time I drive that Corvette, step on the gas, and try to take advantage of that 638 Horsepower/604 ft-lbs of torque 6.2 liter V-8 motor going around a corner? Let's just say you would not be reading any more of good 'ol Dr. Steve's blog postings.
The point I am trying to make is that your FICON storage area network (SAN) (including the channel extension devices), is the tires of your mainframe infrastructure. If you are upgrading your mainframe from an older platform (Chevy Cavalier), to a newer, high performance machine (Chevy Corvette) and not upgrading your FICON infrastructure (tires) you are not going to get the best use of the expensive investment in the new machine. Far too many end users who have undergone mainframe upgrades in the past and have the M6140 FICON directors have elected to upgrade the processor, and upgrade the storage without upgrading the tires and they continued with the M6140s, USDX, etc. Did investing in a new z196 and running FICON Express8S channels with a M6140 make any sense at all? Do you think you achieved the I/O performance you paid a premium for? While the M6140, Mi10K, USDX and Edge 3000 were great platforms, they were great platforms designed for the technology of their time (2002-2006). IBM has seen that, and wisely those older platforms will not be supported/qualified with the zEC12.
If you are considering/planning an upgrade to the zEC12, and have not yet upgraded to the Brocade DCX/DCX 8510 you owe it to yourself to investigate the platform. Brocade has a long history of close partnership with IBM in the mainframe space going back 25 years to parallel channel extension. That experience includes several patents/co-patents with IBM. Our competition lacks the experience/knowledge, and their hardware lacks the energy efficiency, management, and performance that the DCX/DCX 8510 offer. We offer the industry's only FICON architecture certification program and course as well as more advanced training on performance and other topics. And most importantly, mainframe connectivity is a crucial part of our business that we focus on and invest in. You will see that as we continue to announce enhancements with our mainframe connectivity products designed to work in close synergy with these recent enhancements from IBM.