IBM i Runs On Two Of Five New Power8 Machines
April 28, 2014 Timothy Prickett Morgan
Big Blue was widely expected to trot out the new entry Power Systems machines based on its Power8 processors this week, but it looks like the company wanted to make sure that the machines had a day of their own rather than being a part of the broader discussion about big data and cloud at the Impact2014 shindig that IBM is hosting. The interesting bit of news for IBM i shops that came out last week as IBM preannounced the Power8 systems is that there are five new systems, but only two of them are certified to run IBM i.
This was a bit unexpected, but once the pricing for the new machines is divulged, very likely this week, all will be made clear.
IBM is still planning to host an event online to formally announce the Power8 entry servers on April 28, which we told you about two weeks ago and which Big Blue still wants you to participate in. (I will be on an airplane on that day, traveling down to an ARM server chip conference in Austin, Texas, so I am pleased as punch that IBM jumped the gun a little on the Power8 machines. We will nonetheless listen in on what IBM has to say here at The Four Hundred and report back to you if you can’t make the event.) Doug Balog, general manager of the Power Systems division, is hosting the event, and Bob Picciano, senior vice president of the Information and Analytics Group, will also be speaking along with Arvind Krishna, general manager of development and manufacturing within Systems and Technology Group. Ian Buck, vice president of accelerated computing at graphics chip and GPU coprocessor maker Nvidia is also going to talk about the collaboration between the two companies in creating hybrid CPU-GPU systems. You can register for the online event here.
IBM held a separate Power Systems and OpenPower event last Wednesday in San Francisco to show off the new entry Power8-based machines. The initial batch of machines are the traditional rack and tower machines that the IBM i and AIX bases are used to and they do not include any funky converged systems, blade servers, or hyperscale system designs. That doesn’t mean such machines are not coming from Big Blue, or indeed from some of its OpenPower Foundation partners. It just means that they are not coming out now.
The new machines are all based on the 12-core Power8 processor, which we have been telling you all about since last August when IBM first started providing some details on the chip. The Power8 chip is etched using IBM’s 22 nanometer copper and silicon-on insulator (SOI) processes, and the chip has 96 MB of L3 cache on the die along with the dozen cores and a slew of accelerators as well as integrated PCI-Express and NUMA controllers. The latter allows for up to 16 processors to be linked gluelessly together into a single system image, providing 192 cores and 16 TB of main memory per system. IBM is not, however, announcing such a machine now. Rather, the initial Power8 machines, as The Four Hundred already told you, focus on entry machines. These are not only appropriate for running typical IBM i workloads, but can also be clustered together to run various kinds of data analytics and supercomputing workloads.
The Power8 systems incorporate technology that is backed by hundreds of new patents, according to IBM, and are the result of more than $2.4 billion of investment over the past three years. Those numbers were not fully explained, but presumably include the cost of shifting from 32 nanometer processes used with the Power7+ chips down to the 22 nanometer processes used with the Power8. Even for IBM, this is a big investment, although it pales in comparison to the money that Big Blue shells out for share buybacks each year, which is on the order of 15X larger than the annual investment in Power Systems based on that $2.4 billion figure.
To emphasize the scale-out rather than scale-up nature of the new Power8 machines, these first rack and tower machines are known as the Power Systems S-Class machines, with the S presumably standing for scale-out. (This begs the question of what IBM will call scale-up boxes that come to market later. Both words start with S, after all.)
There are five new Power Systems S-Class machines coming. Two of them are Linux-only machines that until now would have been branded PowerLinux in prior years. Presumably, the Linux-only machines have lower prices for processors, memory, and storage to better compete with X86 iron. Full pricing is not being announced until next week, when the announcement was originally scheduled, so we will have to wait to see how these new Power8 machines stack up in terms of bang for the buck.
I was guessing that IBM would brand these machines OpenPower, like the foundation that IBM created to license Power chip and system technology to create an ecosystem to counter the substantially larger and deeper and wider ecosystem created by Intel. If IBM can get some of the larger hyperscale cloud providers to build on Power8 chips–mainly due to the larger cache memory, memory bandwidth, and I/O bandwidth relative to Intel’s Xeon processors and the fact that the Power chips have long since supported Linux–this could help to turn around the Power chip at IBM and maybe even IBM’s own system business. That appears to be the idea. The good news for IBM i shops is that the same processor that works for high-end NUMA machines and scale-out hyperscale clusters also works, when geared down a bit, in small and medium businesses that use the IBM i operating system.
There is actually a naming convention to the new S-Class Power Systems machines. The first part of the name is S, followed by an 8 designating Power8. (What happens with Power8+ chips? Will we put a plus on the end?) The next number of the number of sockets in the box (one or two in the case of these entry machines), followed by the height of the rack version of the machine in standard units (in this case 2 or 4 for 2U or 4U.) The Linux-only machines end in L, the general purpose machines don’t have any letter designation attached to the end.
The Power S812L and S822L Linux-only machines as well as the Power S822 all look alike and it is the machine at the top of the picture above, and the Power S814 and Power S824 general-purpose machines are the chassis at the bottom. These are very similar to the enclosures used in the entry and midrange Power7+ machines that were announced last year. There are some differences aside from the new motherboards and processors that are required with the Power8 processors.
One big change is that the new machines have more PCI-Express peripheral slots, which is made possible through the move to PCI-Express 3.0 controllers on the Power8 chip, explains Steve Sibley, director of worldwide product management for IBM’s Power Systems line. IBM has also tweaked the PowerVM hypervisor that is always present on a Power-based server (even if you are not using logical partitioning) and allowed that hypervisor to do hot-plugging on PCI-Express peripheral cards. IBM had such hot-plugging capability on Power 520, Power 550, and Power 570 systems from the Power5 and Power5+ generations nearly a decade ago, but this function was deprecated in later Power6 and Power7 generations. PowerKVM, a variant of the popular open source hypervisor that is commonly paired with the OpenStack cloud controller and that is controlled by Red Hat, is also available on the new machines, but it does not yet have this PCI-Express hot-plugging. One other change in the system is that IBM is now allowing microthreading on logical partitions, which allows for a partition to run on as few as two threads in a system, whether it is running the PowerKVM hypervisor or IBM’s own PowerVM hypervisor. Each Power8 chip has as many as 96 threads, which means it can support up to 48 logical partitions in theory. The virtualization layer buried inside of PowerVM supported up to 10 partitions per core on Power5 through Power7 processors and up to 20 per core on Power7+ iron, to a maximum of 1,000 partitions in any system. It is not clear which method is better for what purposes, and I will be examining that in a future edition of The Four Hundred. What I can tell you is that all three operating systems–IBM i, Linux, and AIX–will be able to run using the new microthreading approach as well as on the older method, which used a different abstraction method. I would not be surprised at all if IBM eventually allows for a partition to run in a single thread, thereby doubling up the number of potential VMs per machine.
The two Linux-only machines–the Power S812L and the Power S822L–are not going to be particularly interesting to IBM i shops, unless they want to build separate Linux clusters to run workloads rather than fire up Linux on a logical partition inside of their main machines. (There are reasons to want such isolation.) One of the general purpose machines, the Power S822, only runs AIX or Linux, not IBM i. I will have to see more pricing and configuration information before I know how annoyed I am by this. It may not be a big deal. That leaves two machines out of five that run IBM i, and IBM i 7.1 (which was just updated with Technology Refresh 8) and 7.2 (which has yet to be announced but will probably come out next week or at COMMON) are the only two releases supported on the new Power8 iron.
The Power S814 comes in a 4U rack and has a single Power8 processor inside of it. There are two processor options: a six-core chip that runs at 3.02 GHz and an eight-core chip that runs at 3.72 GHz. The Power8 chip has an approximate target operating range of between 2.5 GHz and 5.5 GHz, so these are a little lower than the 4 GHz speed that IBM was showing in early benchmark tests last summer. This machine is clearly aimed at customers who might otherwise want a Power 720 or Power 720+ machine but who wanted more peripheral expansion room than a 2U enclosure offers. The system supports between 16 GB and 512 GB of main memory, has seven PCI-Express 3.0 peripheral slots, and room for a dozen small form factor (2.5-inch) disk drives or flash drives. With an expansion unit that attaches to the server backplane, this machine can have 18 drives attached to it. For further expansion, another 14 of IBM’s EXP24S peripheral drawers can link to the system, for a total of 348 drives and using 1.2 TB SAS disk drives, that works out to a maximum of 417 TB of disk capacity. This machine is the closest analog to a Power 720 or Power 720+ in the S-Class lineup. It has a rating of between 59,500 and 85,500 on the Commercial Performance Workload (CPW) benchmark that IBM uses to gauge the relative performance of IBM i and predecessor platforms.
The Power S824 comes in the same 4U chassis and allows customers to have one or two processor cards, each with 512 GB of main memory. There are three different processor options. The first has a six-core Power8 chip running at 3.89 GHz and the second has an eight-core Power8 chip running at 4.15 GHz. Customers can buy one or two of these for the system. The latter option has a 12-core Power8 chip running at 3.52 GHz, and customers have to buy two of these cards at the same time for a total of 24 cores in the system. This machine has seven PCI-Express 3.0 slots with a single processor card and 11 slots when the second processor card is added. This box has the same disk and flash peripheral expansion options as the Power S814 machine. It is rated at between 72,000 and 230,500 CPWs.
Both of these machines can run IBM i in addition to AIX 6.1 and 7.1 as well as Red Hat Enterprise Linux 6.5 and SUSE Linux Enterprise Server 11 SP3.
For those customers who are interested in packing more compute into a given space, the Power S822 is probably more appropriate, but it only runs Linux or AIX. This machine can have two processor cards, each with a maximum of 512 GB of main memory. There are two processor options for this machine, a six-core chip running at 3.89 GHz and a 10-core chip running at 3.42 GHz. This box has six PCI-Express 3.0 slots with the base processor card and adds an addition three more with the second processor card. The 2U chassis has room for eight 2.5-inch drives plus another six 1.8-inch units, and can have the same 14 EXP24S expansion bays hanging off it for additional storage that the other Power8 servers have. This might be a better machine for a lot of IBM i customers, depending on the price and their processing needs, but it is not an option.
The two Linux-only machines have two processor options: a 10-core chip running at 3.24 GHz and a 12-core chip running at 3.02 GHz. The Power S812L has one socket and the Power S822L has two sockets. Each socket comes with a base 16 GB of memory, expandable to 512 GB. The Power S812L has room only for eight 2.5-inch drives while the Power S822L rolls in the six 1.8-inch drives. IBM does not provide relative performance metrics for Linux workloads, so we have no easy way to tell how much more oomph these have compared to existing OpenPower servers based on Power7 and Power7+ processors.
In addition to running RHEL 6.5 and SLES 11 SP3, these two Linux-only machines are also able to run href=”http://www.canonical.com”>Canonical’s just-announced Ubuntu Server 14.04 LTS variant of Linux. This is the first time that Ubuntu Server has been officially supported on IBM’s Power Systems line.
IBM said that starting prices for the Power8 S-Class machines will start $7,973, but did not provide any information about what that configuration is. You want to know my guess on pricing? The two Linux-only machines will be priced very aggressively to compete directly against X86 iron. The Power S822 machine that runs only AIX or Linux (but not IBM i) will be priced a little less aggressively, and customers going for the two IBM i machines will pay a premium. We have seen this thing before.
Next week, when detailed pricing information is available, I will start building the competitive analysis to help you figure out what the new machines cost. You have time. The Power S812L machine is not available until August, and the four other Power8 machines will not ship until June 10.
IBM will no doubt provide a lot more comparisons with X86 processors, and the performance gains that the Power8 machine offer over Xeon iron will obviously depend on the workloads. Generally speaking, Sibley says that a server running commercial workloads like ERP software or Java applications will see a factor of 2X performance boost on system with two 12-core Power8 processors compared to a machine using two top-end 12-core Xeon E5-2600 v2 processors from Intel. We will be gathering up all of the performance data and looking at this very closely, as you might imagine.