SAPonPower

An ongoing discussion about SAP infrastructure

HPE, still playing fast and loose with the facts about SAP HANA on Power

Writing a blog post would be so much simpler if IBM permitted me to lie, but that is prohibited.  That is clearly not the case at HPE, see this recent blog post: https://community.hpe.com/t5/Alliances/SAP-HANA-runs-best-on-x86-Period/ba-p/6971659#.WZxDPa01TxW

It contains so many lies, it is hard to know where to start.   Let’s start with the biggest one.  There is a 10x difference in performance KPIs required by SAP to certify and ship a HANA appliance vs. a solution certified for TDI only.

You really have to love those lies that are refuted by such easily obtained facts from documentation that is apparently not used by HPE called SAP Notes.  SAP note 1943937 specifically states: All HWCCT tests of appliances (compute servers) certified with scenario HANA-HWC-AP SU 1.1 or HANA-HWC-AP RH 1.1 must use HWCCT of SAP HANA SPS10 or higher or a related SAP HANA revision”  Interesting that appliances must use the same HWCCT test of SAP KPIs as used by TDI.  So, based on HPE’s blog post, does this mean that if an HPE appliance compute server is used for TDI, it will perform 10x worse than if it is used in an appliance? That would imply that the secret sauce of HPE’s appliances is so incredible that it acts like a dual turbocharger on a car!

The blog post goes on to say “It (Power) ‘works’ … but it is just held to a ~10x lower standard without any of the performance optimizations attributed to SAP’s co-innovation efforts with Intel.”  OK, two lies in one sentence, obviously going for the gold here.  As we have already discussed the 10x lie, let us just look at the second one, i.e. performance optimizations.  Specifically, the blog calls out AVX and TSX as the performance optimizations for the Intel platform.  They are correct, those optimization don’t work on Power as, instead of AVX (Advanced Vector Extensions), Power has two fully symmetric vector pipelines called via VSX (Vector-Scalar eXtensions) instructions which HANA has been “optimized” to use in the same manner as AVX.  And TSX, a.k.a. Transactional System Extensions, came out after POWER8 Transactional Memory, but HANA was optimized for both at the same time.

The blog post also stated “Intel E7v3 CPUs for HANA (TSX and AVX) that offer a 5x performance boost over older Intel E7 or Power 8 CPUs.“  Awesome, but where is the proof behind this statement?  Perhaps a benchmark?  Nope, not one published on SAP’s site, even the old SD benchmark backs up this claim (which shows, by the way, almost the same SAPS/core for E7v3 vs. E7v2 and way less than POWER8, but maybe that benchmark does not use those optimizations?  Ok, then maybe the sizing certifications show this?  Nope.  A 4 socket CS500 Ivy Bridge system (E7v2) is published as supporting up to a 2TB SoH solution where a 4 socket CS500 Haswell systems (E7v3) is shown as supporting up to a 3TB SoH solution.  So far, that is just 50% more, not 5x, but perhaps HPE can’t tell the difference between 0.5 and 5.0?  But didn’t Haswell have more cores per socket?  Yes, it had 18 cores/socket vs. 15 cores/socket for IvyBridge, i.e. 20% more cores/socket.  So, E7v3 based systems could actually host 25% more memory and associated workload than E7v2 based systems per core.  Of course, I am sure that the switch from DDR3 to DDR4 from E7v2 to E7v3 had nothing to do with this performance improvement.  So, 5x performance boost is clearly nothing but a big fat lie.

And the hits just keep coming.  The next statement is just lovely “Naturally, this only matters if you want to be able to call SAP support to get help on nuance performance issues impacting your productive SAP HANA deployment.“  I guess he is trying to suggest that SAP won’t help you with performance problems if you are running any TDI solution including Power Systems, except this is contradicted by all of the SAP notes about TDI and HWCCT, not to mention the experience of customers who have implemented HANA on Power.

IBM wants to be the king of legacy businesses like mainframe and UNIX. That’s pretty much the only platforms they have left. So now that they can state that HANA “works” on Power, they can make a case to their AIX/Power customers that they should stay on AIX/Power for SAP and HANA and avoid what IBM claims to be an “oh so painful’ Unix to x86 migration.“  HPE, suggesting that you can run HANA on AIX/Power since HANA only runs on Linux/Power, might not be telling a lie but might just be expressing ignorance and the inability to use sophisticated and obscure search tools like Google.   As to the suggestion of IBM having said that a SAP heterogeneous migration is “oh so painful” ignores the fact that we have done hundreds of such migrations from HP/UX among others.  Perhaps the author is reflecting HPE’s migration experience with what every other migration provider sees as very well understood and fully supported SAP process.  As to IBM’s motivation, HPE is trying to suggest that IBM is only in the HANA business to support its legacy SAP on AIX/Power.  Just looking at the thriving business of HANA on Power, over 850 HANA on Power wins since becoming a supported HANA provider, might suggest otherwise.  How about the complete absence of any quotes, marketing materials or other documentation that shows that IBM is in this market for any other reason than it is the future of SAP and IBM intends to remain a premier partner of SAP and our customers?

Taken together, this blog post shows that HPE must be using the advanced Skylake processors in their Superdome-X and MC990 X (SGI UV 300H) to generate lies at an astounding pace.  Oh wait, I forgot (not really) that HPE still has not announced support for Skylake in their high end systems and is only certified for BWoH, not SoH or S/4HANA, with Skylake and only up to 3TB at that, … one month after announcement of Skylake!  Wow, I guess this shows simultaneously how much their pace of technology innovation has slowed down and partnership with SAP has decreased!

And, let’s end on their last amazing sentence, “Every day you put off that UNIX to x86 migration, you are running HANA in a performance degraded mode with production support limitations.“  Yes, HPE seems to be recommending that you migrate your UNIX based systems, i.e. those running Business Suite 7, to x86.  In other words, do two migrations, once from UNIX to x86 and a second to HANA.  Sounds like a totally disconnect from business reality!  As to the second part of that sentence, it simply does not make sense, so we are not going to attribute that to a lie, but to a simple logic error.

What are we to conclude about this blog post?  Taken on its own, it is a rogue employee.  Taken with the deluge of other similar misleading and outright lies emerging from HPE and we see a trend.  HPE has gone from being a well-respected systems supplier to a struggling company that promotes and condones lies and hires less than competent individuals to propagate misinformation.  Sounds more like a failing communist state than a company worthy of a customer’s trust.

Advertisements

August 22, 2017 Posted by | Uncategorized | , , , , , , , , | 4 Comments

HANA on Power hits the Trifecta!

Actually, trifecta would imply only 3 big wins at the same time and HANA on Power Systems just hit 4 such big wins.

Win 1 – HANA 2.0 was announced by SAP with availability on Power Systems simultaneously as with Intel based systems.[i]  Previous announcements by SAP had indicated that Power was now on an even footing as Intel for HANA from an application support perspective, however until this announcement, some customers may have still been unconvinced.  I noticed this on occasion when presenting to customers and I made such an assertion and saw a little disbelief on some faces.  This announcement leaves no doubt.

Win 2 – HANA 2.0 is only available on Power Systems with SUSE SLES 12 SP1 in Little Endian (LE) mode.  Why, you might ask, is this a “win”?  Because true database portability is now a reality.  In LE mode, it is possible to pick up a HANA database built on Intel, make no modifications at all, and drop it on a Power box.  This removes a major barrier to customers that might have considered a move but were unwilling to deal with the hassle, time requirements, effort and cost of an export/import.  Of course, the destination will be HANA 2.0, so an upgrade from HANA 1.0 to 2.0 on the source system will be required prior to a move to Power among various other migration options.   This subject will likely be covered in a separate blog post at a later date.  This also means that customers that want to test how HANA will perform on Power compared to an incumbent x86 system will have a far easier time doing such a PoC.

Win 3 – Support for BW on the IBM E850C @ 50GB/core allowing this system to now support 2.4TB.[ii]  The previous limit was 32GB/core meaning a maximum size of 1.5TB.  This is a huge, 56% improvement which means that this, already very competitive platform, has become even stronger.

Win 4 – Saving the best for last, SAP announced support for Suite on HANA (SoH) and S/4HANA of up to 16TB with 144 cores on IBM Power E880 and E880C systems.ii  Several very large customers were already pushing the previous 9TB boundary and/or had run the SAP sizing tools and realized that more than 9TB would be required to move to HANA.  This announcement now puts IBM Power Systems on an even footing with HPE Superdome X.  Only the lame duck SGI UV 300H has support for a larger single image size @ 20TB, but not by much.  Also notice that to get to 16TB, only 144 cores are required for Power which means that there are still 48 cores unused in a potential 192 core systems, i.e. room for growth to a future limit once appropriate KPIs are met.  Consider that the HPE Superdome X requires all 16 sockets to hit 16TB … makes you wonder how they will achieve a higher size prior to a new chip from Intel.

Win 5 – Oops, did I say there were only 4 major wins?  My bad!  Turns out there is a hidden win in the prior announcement, easily overlooked.  Prior to this new, higher memory support, a maximum of 96GB/core was allowed for SoH and S/4HANA workloads.  If one divides 16TB by 144 cores, the new ratio works out to 113.8GB/core or an 18.5% increase.  Let’s do the same for HPE Superdome X.  16 sockets times 24 core/socket = 384 cores.  16TB / 384 cores = 42.7GB/core.  This implies that a POWER8 core can handle 2.7 times the workload of an Intel core for this type of workload.  Back in July, I published a two-part blog post on scaling up large transactional workloads.[iii]  In that post, I noted that transactional workloads access data primarily in rows, not in columns, meaning they traverse columns that are typically spread across many cores and sockets.  Clearly, being able to handle more memory per core and per socket means that less traversing is necessary resulting in a high probability of significantly better performance with HANA on Power compared to competing platforms, especially when one takes into consideration their radically higher ccNUMA latencies and dramatically lower ccNUMA bandwidth.

Taken together, these announcements have catapulted HANA on IBM Power Systems from being an outstanding option for most customers, but with a few annoying restrictions and limits especially for larger customers, to being a best-of-breed option for all customers, even those pushing much higher limits than the typical customer does.

[i] https://launchpad.support.sap.com/#/notes/2235581

[ii] https://launchpad.support.sap.com/#/notes/2188482

[iii] https://saponpower.wordpress.com/2016/07/01/large-scale-up-transactional-hana-systems-part-1/

December 6, 2016 Posted by | Uncategorized | , , , , , , , , , , , , , , , , , , , | 3 Comments

Haswell-EX for HANA looks good on paper, POWER8 for HANA looks even better in real life

I was delighted to read Hasso Plattner’s recent blog on the strengths of HANA on platforms using the Haswell-EX chip from Intel:  https://blogs.saphana.com/2015/06/29/impact-of-haswell-on-hana/  In that blog, he did an excellent job of explaining how technical enhancements at a processor and memory subsystem level can result in dramatic improvement in the way that HANA operates,   Now, I know what you are thinking; he likes what Dr. Plattner has to say about a competitor’s technology?   Strange as it may seem, yes … in that he has pointed out a number of relevant features that, as good as Haswell-EX might be, POWER8 surpassed, even before Haswell-EX was announced.

All of these technical features and discussion are quite interesting to us propeller heads.   Most business people, on the other hand, would probably prefer to discuss how to improve HANA operational characteristics, deliver flexibility to respond to changing business demands and meet end user SLAs including response time and continuous availability.  This is where POWER8 really shines.  With PowerVM at its core, Power Systems can be tailored to deliver capacity for HANA production to ensure consistent response time and peak load capacity during high demand times and allow other applications and partitions to utilize capacity unused by the HANA production partition.   It can easily mix production with other production and non-production partitions.  It features the ability to utilize shared network and SAN resources, if desired, to reduce datacenter cost and complexity.  POWER8 delivers unmatched reliability by default, not as an option or a tradeoff against performance.

Regarding the technical features, Herr Dr. Plattner points out that Haswell-EX systems:

  • Support up to 144 cores per system with 12TB of memory.  POWER8 supports up to 196 cores and 16TB.  Actually, this under estimates that actual memory on a POWER8 system which is actually up to 17.7TB but IBM includes the extra 1.7TB at no extra cost as hot spare chips, not available with Haswell-EX systems.
  • Deliver L1, L2 and L3 cache size increases, which though he does not state, are, in fact, 32KB (16KB in enterprise RAS mode), 256KB and 45MB respectively, compared to POWER8’s 64KB, 512KB and 96MB respectively plus 128MB L4, not available with Haswell-EX systems.
  • Introduces enhancements to vector processing via the new AVX2 instruction unit compared to  POWER8’s dual VMX instruction units.
  • Rely on local memory access for HANA performance which is absolutely true and underlines why POWER8, with up to 4 times more bandwidth to memory, is such a good fit for HANA.
  • Feature TSX, Transactional Synchronization Extensions, to improve lock synchronization, an area that Power Systems has excelled at for decades.  POWER8 was actually a bit earlier in the whole transactional memory area but was actually preceded by IBM Blue Gene/Q, another PowerPC based technology.

He concludes by pointing out that internal benchmarks are of limited value but then explains what they achieved with Haswell-EX.  As these are not externally audited nor even published, it is hard to comment on their validity.

By comparison, SAP has only one certified benchmark for which HANA systems have been utilized called BW-EML.  Haswell-EX cpus were used in the 2B row Dell PowerEdge 930 benchmark and delivered an impressive 172,450 Ad-hoc Navigation Steps/Hr . This is impressive in that it surpassed the previous IvyBridge based benchmark of 137,010 Ad-hoc Navigation Steps/Hr on the Dell PowerEdge R920, an increase of almost 26% which would normally be impressive if it weren’t for the fact that the system includes 20% more cores and 50% more memory.  By comparison, POWER8 delivered 192,750 Ad-hoc Navigation Steps/Hr with the IBM Power Enterprise System 870 or 12% more performance with 45% fewer cores and 33% less memory resulting in twice the performance per core.

It would be ideal to run the SAP SD 3-tier benchmark against a system running Suite on HANA as that would do away with discussions of benchmarks that can’t be verified and/or may have limited relevance to a transactional environment typical of Suite on HANA.  From what I understand, the current SD benchmark depends on an older version of SAP code which is not supported on HANA.  I hope that SAP is able to update the benchmark test kit to enable this benchmark to be run on HANA as that would be far better than any sort of speculation.  In the meantime, we can only rely on assertions without detail and external review or on decades of proven experience handling large scaling transactional environments with mission critical levels of availability not to mention a wide variety of audited benchmarks demonstrating this ability.  Power Systems stands alone in this respect.

Benchmark details:

Dell PowerEdge 930: 172,450 Ad-hoc Navigation Steps/Hr using 4 processors / 72 cores / 144 threads, Intel Xeon Processor E7-8890 v3, 2.50 GHz, 1.5TB main memory, Certification #: 2015014

Dell PowerEdge R920: 137,010 Ad-hoc Navigation Steps/Hr on the, 4 processors / 60 cores / 120 threads, Intel Xeon Processor E7-4890 v2, 2.80 GHz,  1TB main memory, Certification #: 2014044

the IBM Power Enterprise System 870: 192,750 Ad-hoc Navigation Steps/Hr with, 4 processors / 40 cores / 320 threads, POWER8, 4.19 GHz,  1TB main memory, Certification #: 2015024

July 22, 2015 Posted by | Uncategorized | , , , , , , , , , , , | Leave a comment