IBM’s Power8 Enterprise Systems Loom
Back in July, as EnterpriseTech has previously reported, IBM's chief financial officer, Martin Schroeter, said that Big Blue was working on fleshing out the midrange and high-end of the Power Systems lineup with new Power8-based systems. At the time, IBM was pretty vague about the timing, but the word on the street is that Big Blue is looking to do the announcements at its Enterprise2014 conference in Las Vegas during the first week of October.
That conference combines a two-day, customer-driven executive conference with over four days of technical content relating to the Power Systems family as well as the System z mainframes. This is, in effect, what will remain of the IBM systems business once the company closes its $2.3 billion deal to sell off its System x X86 server division to Lenovo Group, which should happen any day now that the major regulatory bodies in the United States, Europe, and China have given the green light to the deal.
Tom Rosamilia, who is senior vice president of IBM Systems and Technology Group and Integrated Supply Chain, is hosting the event and Doug Balog, who is general manager of the Power Systems division, will also be a keynote speaker. No one is expecting any major announcements from the System z line, and new System z general manager Ross Mauri is not one of the highlighted keynotes. So it looks like we will have to wait until next year to see the System z13 mainframe lineup.
IBM has given hints about what its larger Power8 machines would look like, saying that these "enterprise-class Power Systems" will combine the resiliency features of the top-end Power 795 machines and offer "substantial improvements" in energy and space efficiency. IBM has said further that the machines will have a modular design, which is nothing new. IBM has been shipping modular enterprise-class Power-based systems since the Power5 generation a decade ago. These modular machines lash together multiple server enclosures using NUMA electronics that were inspired by its Sequent Computer acquisition in 2003 and that have been substantially enhanced over the years. IBM has also said that there will be an upgrade path from the existing Power 770+ and Power 780+ machines, which come in NUMA clusters with between one and four enclosures with a total of between four and sixteen sockets; depending on the Power7+ processor chosen, these machines range from 12 to 64 cores. The Power 795, which dates from 2010, has from four to 32 sockets in a single system image and spans from 24 to 256 cores. It only uses the earlier eight-core Power7 chips, not the enhanced Power7+ variant.
The question everyone wants to know is whether or not IBM will debut a follow-on to the Power 795 or just upgrade the Power 770+ and Power 780+ machines and be done with it. The Power 795, at 16 TB, has a much larger memory footprint than its two smallest siblings, which top out at 4 TB. The NUMA electronics on the Power8 chip aimed at scale-up workloads has a much flatter interconnect than that used in the Power7 and Power7+ generations, and based on our back-of-the-envelope math, it looks like a 16-socket Power8 machine could have the same or better aggregate performance with 128 cores as a Power7-based Power 795 with 256 cores. With 16 sockets and 12 Power8 cores per socket, IBM could push the performance further with a total of 192 cores. How much more really depends on the clock speeds it can deliver with a real twelve-core Power8 chip. The entry Power S812 and S824 machines have two six-core Power8 chips that share a single socket and that have lots more I/O bandwidth. The scale-up, single-die Power8 chips are designed for large NUMA systems and have less I/O capability.
IBM could add more NUMA node controllers to the outside of the Power8 chips, but the more we think about it, the more we think IBM will not do this. The engineering cost, the additional complexity in the product line, and the revenue payoff may not make sense. Of course, Oracle is moving in the opposite direction, with Sparc M6 platforms that have 32 sockets and support 32 TB of memory and with next year's 32-core Sparc M7, Oracle will be able to have 32 sockets, 1,024 cores, 8,192 threads, and up to 64 TB of main memory in a single system image.
IBM established a naming convention for the Power8 servers, with the S standing for Scale-Out (meaning loosely coupled clusters instead of tight NUMA clustering), the 8 standing for Power8, the next number standing for the number of sockets in the system, and the final number being the size of the server in terms of rack units. If you tack an L onto the name, it means it only supports Linux and it has a lower price tag. With these being Enterprise machines, it is logical that the names of the forthcoming machines will start with an E and then follow with an 8. The number of sockets will be four or eight and the rack size will be hard to gauge because it is a multi-chassis unit. IBM may throw the whole naming convention out the door and just call the new machines the Power E870 and Power E880 and be done with it.
It is not clear what IBM intends to do to fill out the midrange of its product, where it has to fight four-socket servers from Intel and Oracle. Usually, IBM has a cost-effective four-socket machine that is distinct from (and cheaper than) the first node in an enterprise-class NUMA box based on Power chips. We have heard nothing about any new midrange systems coming out in October, and all of the rumors are for this scale-up machine to come to market, whatever it is called.
IBM has also not said precisely what it plans to do to upgrade its Flex System modular systems with the Power8 processors. The company may simply be waiting for the Lenovo deal to close to reveal its plans, since Lenovo will take over the entire Flex System line, including the chassis, the networking, and the Xeon-based server nodes and excepting any Power-based nodes that IBM still intends to build to be compatible with the Flex Systems. It is perplexing why IBM did not already launch nodes based on Power8 for the Flex System iron, considering how it wants to promote Power and how it wants to take on Cisco Systems, Dell, and Hewlett-Packard for converged infrastructure.
