Expanded Power Systems i Boxes on the Horizon?
September 8, 2008 Timothy Prickett Morgan
It has been a quiet summer in Lake Woebegone, er, rather Rochester, Minnesota, and its Silver Lake. The run from late June through September is traditionally a quiet one, with a few nips and tucks here and there in the Power Systems lineup. But as we all know from reading The Four Hundred, IBM still has a little unfinished Power Systems business for 2008. And the word on the street is that some tweaked gear might be coming down the pike any day now.
Heaven only knows if what I am hearing is true, because Big Blue doesn’t usually confirm or deny such rumors. But what I am hearing–and also what I expect in addition to what I am hearing–certainly sounds plausible.
First, the rumors. I am hearing from sources who are hearing from their resellers and their sources within IBM that the Power 550 midrange box and the Power 570 enterprise-class box are set to be expanded with more processing capacity. Specifically, I hear that IBM is going to double up the processor core count on the Power 550 to eight Power6 cores and double up the Power 570 to 32 cores.
It is unclear if IBM might use twice as many processor sockets to accomplish this expansion, or if it is moving to dual-chip modules that would package two dual-core Power6 chips in a single package and have them share a single socket. IBM has put two dual-core chips inside Power5 and Power5+ machines for its supercomputing customers, where sometimes thermal issues and core counts matter more than the peak processing capacity of a single core. Such dual-chip modules usually mean stepping the clock speed back a bit–perhaps down to 3 GHz in the Power6 family of processors from the 5 GHz top-end speed–but the resulting reduction in speed and the doubling of cores results in a net increase in processing capacity within the same thermal envelope or lower. This approach allows IBM to pack more cores into a smaller space, and this has certainly been important in the supercomputing space. In the past, when IBM was doing this for supercomputers and as well as to make its AIX-based System p boxes competitive with dual-core X64 boxes running any kind of workloads, the System i top brass told me that this doubling up of chips in a socket did not work well for System i workloads because of L2 cache and L3 cache issues. (IBM sometimes cut back on the cache to make these chip modules.) Whether or not this could still be the case with Power6 chips is unclear.
The question you really have to ask is why IBM might do this at all? It may be that customers putting in lots of cores in the Power 570 class don’t want to have multiple chasses to get those cores, so they want IBM to deliver a beefier Power 550 box. The same would hold true for customers who might want the processing capacity of an entry Power 595 box, but they don’t want to change to the larger rack style of the Power 595 or pay a premium for the 64-core expansion in the high-end box. And, of course, it always comes back to software tiers. Customers might be pressuring IBM to get more oomph into these software tiers.
I said might. The information I have right now is pretty thin. So don’t bet your budget on this. But do call IBM if you are acquiring a Power 550 or Power 570 and get them to spill. (And then, you can send me an email if you are feeling generous to your fellow readers.)
What I do know for sure, which I already told you about earlier this year, is that IBM is expected to really converge the Power Systems lineup in the September or October timeframe, eliminating the i Edition and AIX and Linux Edition distinctions that have prevailed since the spring, when the i platform moved to Power6 iron. IBM’s plans, of course, change.
What I also know is that Power 520 machines are restricted to two cores now in the i Editions, while the AIX and Linux Editions have four cores, and the Power 550 i Edition is restricted to four cores while the AIX and Linux Editions have eight. I think you can see where this is going. IBM is probably just going to have a new set of integrated product numbers and feature codes for Power Systems, with no edition, and turn all the cores on for the i5/OS V5R4 and i 6.1 operating systems. Which, if you will recall, I suggested IBM do last spring. But, had Big Blue done that, it might have put a crimp in Power 570 sales, particularly when you consider that the Power 550 is in the P20 software tier and an eight-core Power 570 is in the P30 tier and that some prior generations of Power5 and Power5+ 570-class machines are in the P40 and P50 tiers. IBM would have seen a whole lot of push-pull system replacements in the past six months it if had made the AIX and i boxes the same in core count. IBM really needed that i platform revenue in the past six months to help make up for a slowing AIX business. Hence, this two-step strategy toward real convergence.
I don’t have high confidence that the Power 570 will see its processor core count doubled, but if IBM does it, this will be an interesting development.