IBM Doubles the Cores on Midrange Power Systems
October 13, 2008 Timothy Prickett Morgan
Well, the rumor going around that IBM is doubling up the processor core counts on its Power Systems servers, which are based on the company’s dual-core Power6 processors, turns out to be true. Last Tuesday, IBM announced that it has doubled up the cores in the Power 570 to a maximum of 32, and now is also offering a 16-core box called the Power 560 that slides in underneath it in the product line. As expected, IBM also doubled the core count on entry Power 520 and midrange Power 550 machines when running the i 6.1 (formerly OS/400 and i5/OS) operating system to four and eight cores, respectively, bringing the i variants to parity with AIX and Linux boxes that shipped in April.
The move to double up the Power6 core counts in some of the Power Systems machines is not just about giving customers headroom. It is also about making the Power6 boxes more competitive against current and future X64, RISC, and Itanium midrange gear from Hewlett-Packard, Sun Microsystems, Fujitsu-Siemens, Dell, NEC, and Unisys–and even IBM’s own System x line of X64 servers.
The Power 560 is interesting in that, for many customers, it has just replaced the Power 570 offering up to 16 cores, but does so in half the space–two linked chasses instead of four. The Power 560 can be equipped with four, eight, or 16 cores running at 3.6 GHz, which is slower than the top-end 5 GHz Power6 parts. Each core has 4 MB of L2 cache, just like in other Power6 machines, and each pair of cores has a 32 MB L3 cache in the chip package. The Power6 chips include AltiVec math units and decimal floating point units, the latter accelerating calculations having to do with money.
Main memory in the Power 560 box expands from 8 GB to 384 GB (it’s DDR2 SDRAM), and each chassis has room for six 3.5-inch SAS drives that link into an on-board SAS controller. The base system comes with two Gigabit Ethernet ports per chassis, with 10 Gigabit Ethernet as an option. The machine supports AIX 5.3 or 6.1, i 6.1 (but not i5/OS V5R4, which is supported on other Power6-based rack machinery), and Linux with the 2.6 kernel (Novell‘s SUSE Linux Enterprise Server SP1 and SP2 and Red Hat‘s Enterprise Linux 4.5 or later and 5.1 or later releases are certified on the machine).
IBM provided list pricing for Power 560 machines configured running AIX and Linux, but did not offer pricing for those running the i 6.1 operating system. A four-core Power 560 with 16 GB of main memory and two 146 GB SAS drives costs $47,216 in a so-called Express configuration, which means it is preconfigured and comes with a modest discount. AIX costs $1,540 per core on top of that, and Linux costs whatever Red Hat and Novell want to charge or what IBM will give you as a Linux reseller. Specifically, that is $719 for RHEL 5 with an unlimited number of sockets and up to 25 logical partitions using IBM’s PowerVM hypervisor and IBM’s own Linux support and $1,349 for the same thing with Red Hat’s support. And SLES is even cheaper, at $315 for a one-year license when backed up by IBM support and $892 with Novell support. A license to i 6.1 appears to cost $40,000 per core, which is the same price it cost on earlier 550-class midrange machines and a lot less than the $53,000 IBM is charging on Power 570 machines.
With the modified Power 570s, there are now two ways to build a system. The Power 570, like its System i and System p predecessors, is really one to four servers lashed together into a single system image by IBM’s own Power chipsets. (In this regard, it is like the System x “Hurricane” x3950 and its predecessors or the new “Monster Xeon” X64 server created by NEC and Unisys.) The old way of building a Power 570 is to scale from one to four boxes and use Power6 cores running at 3.5 GHz, 4.2 GHz, or 4.7 GHz. With last week’s announcements, a 4.4 GHz and a 5 GHz option is now available in the earlier Power 570 boards. The new way to build a Power 570 is to use double-density motherboards that have eight processor sockets per board, for a total of 16 sockets across two chasses, giving the maximum of 32 cores in a single system image. IBM is only offering 4.2 GHz Power6 cores in this new Power 570 box, and that’s due to heating, cooling, and power draw issues, according to Ross Mauri, general manager of IBM’s Power Systems division.
The two variants of the Power 570 run all the same operating systems as the Power 560, except that IBM is also throwing in support for the older i5/OS V5R4. The memory capacity of the Power 570 depends on what speed memory customers use and how many chasses customers. With 667 MHz memory, the maximum capacity per chassis is only 48 GB, but it rises to 192 GB using cooler–and slower–400 MHz DIMMs. Pricing was not available for the doubled-up Power 570 at press time. But you can bet a bunch of AIX and i customers are trying to figure out if they can get away with this new Power 570 instead of having to move to a much more expensive (and yet, more scalable) Power 595 server, the biggest box Big Blue builds.
The Power 560 and the updated Power 570 machines are available on November 21 worldwide.
It is a bit of a mystery why IBM didn’t offer the Power 520 i Edition machines with the full core count back in April, but it is probably just a matter of the company wanting to sell Power 550 boxes to those customers eager to get more oomph than the crimped Power 520s offered, and thereby extracting a bit more dough out of them. (Processing capacity and i 6.1 and i5/OS V5R4 operating system licenses are more expensive on the Power 550 than on the Power 520, and that can tide a server maker over in a tough quarter or two.) The decision may have had something to do with yields on Power6 chips, allowing IBM to get AIX customers the full capacity first and then System i shops (who often don’t need more than one or two cores anyway) the extra headroom later.