Power Systems – Delivering best of breed scalability for SAP HANA
SAP quietly revised a SAP Note last week but it certainly made a loud sound for some. Version 47 of https://launchpad.support.sap.com/#/notes/2188482 now says that OLTP workloads, such as Suite on HANA or S/4HANA are now supported on IBM Power Systems up to 24TB. OLAP workloads, like BW HANA may be implemented on IBM Power Systems with up to 16TB for a single scale-up instance. As noted in https://launchpad.support.sap.com/#/notes/2055470, scale-out BW is supported with up to 16 nodes bringing the maximum supported BW environment to a whopping 256TB.
As impressive as those stats are, it should also be noted that SAP also provided new core-to-memory (CTM) guidance with the 24TB OLTP system sized at 176-cores which results in 140GB/core, up from the previous 113.7GB/core at 16TB. The 16TB OLAP system, sized at 192-cores, translates to 85.3GB/core, up from the previous 50GB/core for 4-socket and above systems.
By comparison, the maximum supported sizes for Intel Skylake systems are 6TB for OLAP and 12TB for OLTP which correlates to 27.4GB/core OLAP and 54.9GB/core OLTP. In other words, SAP has published numbers which suggest Power Systems can handle workloads that are 2.7x (OLAP) and 2x (OLAP) the size of the maximum supported Skylake systems. On the CTM side, this works out to a maximum of 3.1x (OLAP) and 2.6x (OLTP) better performance per core for Power Systems over Skylake.
Full disclosure, these numbers do not represent the highest scaling Intel systems. In order to find them, you must look at the previous generation of systems. Some may consider them obsolete, but for customers that must scale beyond 6TB/12TB (OLAP/OLTP) and are unwilling or unable to consider Power Systems, an immediate sunk investment may be their only choice. (Note to customers in this undesirable predicament, if you really want to get an independent, third party verification of potential obsolesence, ask your favorite leasing companies, not associated or owned by the vendor, what residual value they would assume after 1 year for these systems vs. what they would assume for similar Skylake systems after 1 year.)
The previous “generation” of HPE Superdome, “X”, which as discussed in my last blog post shares 0% technology with Skylake based HPE Superdome “Flex”, was supported up to 8TB/16TB with 384 cores for both OLAP and OLTP, resulting in CTM of 21.3GB/42.7GB/core. The SGI derived HPE MC990 X, which is the real predecessor to the new “Flex” system, was supported up to 4TB/20TB with 192 cores OLAP with 480 cores.
Strangely, “Flex” is only supported for HANA with 2 nodes or chassis where “MC990 X” was supported with up to 5 nodes. It has been over 4 months since “Flex” was announced and at announcement date, HPE loudly proclaimed that “Flex” could support 48TB with 8 chassis/32 sockets https://news.hpe.com/hewlett-packard-enterprise-unveils-the-worlds-most-scalable-and-modular-in-memory-computing-platform/. Since that time, some HPE reps have been telling customers that 32TB support with HANA was imminent. One has to wonder what the hold up is. First it took a couple of months just to get 128GB DIMM support. Now, it is taking even longer to get more than 2-node support for HANA. If I were a potential HPE customer, I would be very curious and asking my rep about these delays (and I would have my BS detector set to high sensitivity).
Customers have now been presented with a stark contrast. On one side, Power Systems has been on a roll; growing market share in HANA, regular increases in supported memory sizes, the ability to handle the largest single image HANA memory sizes of any vendor, outstanding mainframe derived reliability and radically better flexibility with built in virtualization and support for a maximum of 8 concurrent production HANA instances or 7 production with many dozens of non-prod HANA, application servers, non-HANA DBs and/or a wide variety of other applications supported in a shared pool, all at competitive price points.
On the other hand, Intel based HANA systems seem to be stuck in a rut with decreased maximum memory sizes (admittedly, this may be temporary), anemic increases in CTM, improved RAS but not yet to the league of Power Systems and a very questionable VMware based virtualization support filled with caveats, limitations, overhead and poor, at best, sharing of resources.
HPE Superdome is dead, but HPE marketing continues its deceptive ways.
Today, 11/6/17, HPE announced the “New” Superdome Flex. If you did not look too closely, you would think that this was some sort of descendant of Superdome. After all, the Integrity Superdome took the original Superdome and replaced PA-RISC chips and the SX1000 cell controller with Itanium chips and a faster SX2000 cell controller. Superdome 2 took this further by upgrading to the latest Itanium chips, an even faster SX3000 cell controller and moved from a cell board to a blade configuration. Superdome X changed out the Itanium chips for Intel Xeon chips which it upgraded over several generations. So, it would be only natural to think that Superdome Flex did something similar and that is exactly what HPE wants you to think.
Except, this is not even remotely like any prior Superdome and has inherited almost nothing from it. In fact, this is a very straightforward descendant of the SGI UV 300H, which HPE renamed the MC990 X after the acquisition. A glance at the front of the “new” system shows the same basic design, a 4-socket, 5U chassis even down to the unique diagonal handles on the fans, but they apparently moved the NUMAlink fabric ports (no longer called that; renamed Superdome Flex ports) from the back to the front, perhaps to get rid of a little of the rats nest of cables which defined the SGI UV 300H. This means there is no SX3000 or cross bar switch in the Flex and the blade design is gone. Even the memory DIMMS are different which implies that nothing could be moved from an old Superdome X to a new “Flex” other than perhaps some old PCIe adapters.
So, if the entire design is based on an SGI acquired technology and it shares nothing from its “namesake”, one would need to avoided that course in ethics in high school or college to find it appropriate to suggest to customers that this is a related technology. Imagine if Honda changed the engine, frame, transmission, trim and body style but called their new car an Accord “Flex” because it used the same bumper and tire sizes, would you feel as if they were trying to manipulate you?
Back to the more important topic, Superdome is now dead! I have been saying this for a while and blogged about this several months ago. I suggested that any customer considering investing in this technology view it as instantly obsolete and a sunk investment. I pointed out the huge investment in ccNUMA interconnect technologies and how it was hard to imagine how HPE could afford to invest in 2 different ones at the same time, so only one system was likely to survive. I explained that the SGI technology offered more space and power to host the new, larger, higher wattage and heat dissipating Skylake processors. It appears that my projections were correct. For customers that ignored that advice, I just hope you got a really great price and don’t mind paying a lot for old technology for any upgrades or dumping your old systems at a huge financial loss. For any customer still considering a Superdome X, the writing is no longer on the wall. It is on HPE’s web site. https://news.hpe.com/hewlett-packard-enterprise-unveils-the-worlds-most-scalable-and-modular-in-memory-computing-platform/
Currently, no white papers have been published showing the architecture and detailed specs of this “new” system, only a relatively high level “Spec” sheet. Perhaps HPE is too embarrassed to publish this since it would likely resemble the SGI UV 300H in way too many ways, including the old rats nest of 4-bit wide interconnect cables. Once they do, I will investigate and will likely publish a separate post to share what I find.
On the SAP front, new HANA appliance specs have been published for “Flex”. It is interesting, and again embarrassing for HPE, that only up to 8-socket configs are shown, with less BWoH memory support @ 6TB max than the old, and now obsolete, Superdome X. Even more interesting is the lack of SoH and S/4 configs, and I have a suspicion as to why. Turns out that the spec sheet does have one interesting point after all. It shows the maximum size memory DIMMS are 64GB and the number of DIMMS slots is 48 with a max supported memory of 3TB per chassis, i.e. half of what is necessary to support the 6TB per 4-sockets that other competing Intel vendors support.
So, if you need a supported HANA configuration today with current generation processors for BWoH beyond 6TB, look at any vendor other than HPE with 8-socket Skylake systems or IBM Power Systems. If you need a supported SoH or S/4 configuration with current gen processors, look at any vendor other than HPE and beyond 12TB, only IBM Power Systems is supported at this level.
Intel Skylake has been announced and the self-described HANA “market leader”, HPE, is curiously trailing the field
Intel announced general availability of their “Skylake” processor on the “Purely” platform last week. Soon after, SAP posted certified HANA configurations for Lenovo and Fujitsu up to 8 sockets and 12TB memory for Suite on HANA (SoH) and S/4HANA (S4) and 6TB for BW on HANA (BWoH). They also posted certified configurations for Dell and Cisco up to 4-socket systems with 6TB SoH/S4 and 3TB BWoH. The certified configurations posted for HPE, which describes itself as the HANA market leader, only included up to 4-socket/3TB BWoH configurations, no configurations for SoH/S4 and nothing for any larger systems.
It is still early and more certified configurations will no doubt emerge over time, but these early results do beg the question, “what is going on with HPE?” I checked the most recent press releases for HPE and they did not even mention the Skylake debut much less their certification with SAP HANA. If you Google using the keywords, HPE, Skylake and HANA, you may find a few discussions about HPE’s acquisition of SGI and my previous blog posts with my speculation about Superdome’s demise and HPE’s misleading of customers about this impending event, but nothing from HPE.
So, I will share a little more speculation as to what this slow start for HPE in the Skylake space might portend.
Option 1 – HPE is not investing the funds necessary to certify all of their possible configurations and SoH/S4. Anyone that has been involved with the HANA certification process will tell you that it is very time consuming and expensive. As you can see from HPE’s primary Intel based competitors, they are all very eager to increase their market share and acted quickly. Is HPE becoming complacent? Are they having financial restrictions that have not been made public?
Option 2 – HPE’s technology limitations are becoming apparent. The Converged System 500 is based on Proliant DL560/580 systems which support a maximum of 4 sockets. These systems utilize Intel QPI and now UPI interconnect technologies, i.e. no custom ASICs or ccNUMA switches are required. The CS900 based on the Superdome X and the MC990 X (SGI UV 300H) utilize custom ASICs and, in the case of Superdome X, a set of ccNUMA switches. As I speculated previously, Superdome X is probably at end of life, so it may never see another certification on SAP’s HANA site. As to the MC990 X, the crystal ball is a bit more hazy. Perhaps HPE is trying to shoot for the moon and hit a number beyond the 20TB for SoH/S4 that is currently supported meaning a much longer and more complex set of certification tests. Or perhaps they are running into technical challenges with the new ASICs required to support UPI.
Option 3 – MC990 X is going to officially become HPE’s only high end offering to support Skylake and subsequent processors and Superdome X is going to be announced at end of life. If this were to happen, it would mean that anyone that had recently purchased such a system would have purchased a system that is immediately obsolete.
If Option 1 turns out to be true, one would have to concerned about HPE’s future in the HANA space. If Option 2 turns out to be true, one would have to be really concerned about HPE’s future in the HANA space. And if Option 3 turns out to be true, why would HPE be waiting? The answer may be inventory. If HPE has a substantial inventory of “old” Broadwell based blades and Superdome X chassis, they will undoubtedly want to unload these at the highest price possible and they know that the value of obsolete systems after such an announcement would drop into the below cost of manufacturing range.
So, you pick the most likely scenario. Worst case for HPE is that they are just a little slow or shooting too high. Worst case for customers is that they purchase a HANA system based on Superdome X and end up with a few hundred thousand dollar boat anchor. If you work for a company considering the purchase of an HPE Superdome X solution, you may want to ask about its future and, if you find it is at end of life, select another solution for your SAP HANA requirements.
Inevitably, more systems will be published on SAP’s certification page, https://www.sap.com/dmc/exp/2014-09-02-hana-hardware/enEN/appliances.html#viewcount=100&categories=certified%2CIntel%20Skylake%20SP . When that happens, especially if any of my predictions turn out to be true or if they are all wrong and another scenario emerges, I will post an update.
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