SAP HANA – could I have extra complexity please?

Just returned from IBM’s Systems Technical University conference held in Orlando having delivered presentations on 4 different topics.

  1. Benefits of SAP HANA on POWER vs Intel
  2. Why IBM POWER systems are datacenter leaders
  3. Only platform that controls Software Licensing
  4. Why DB2 beats Oracle on POWER (implied that it beats Intel).

With the SAP Sapphire conference last week in Orlando, there was a slew of announcements.  Quick reminder for the uninitiated with SAP HANA, that it is ONLY supported on Intel and POWER based systems running one OS; SUSE or RedHat Linux. With that, IBM POWER continues to deliver the best value.

What is the value offered with the POWER stack? Flexibility! It really is that simple.  If I had a mic on the plane as I write this, I would drop it. Conversely, what is the value offered going with an Intel stack? Compromise!

Some of the flexibility offered thru IBM POWER systems are: Scale-up, scale-out, complete virtualization, grow, shrink, move, perform concurrent maintenance, mix workloads: existing ECC workloads on AIX or IBM i with new HANA running Linux all on the same server.  All of this runs using the most resilient HANA platform available.

Why do I label Intel systems as “Compromise” solutions? It isn’t a competitive shot nor FUD.  Listen, as an Client Executive and Executive Architect for an Channel Reseller, I am able to offer my clients solutions from multiple vendors that include IBM POWER and Intel based systems manufacturers.  I’ve made the conscious decision though to promote IBM POWER over Intel.  Why? Because I not only believe in the capabilities of the platform but also having worked with some of the largest companies in the world, I regularly hear and see the impact running Enterprise workloads on Intel based servers has on the business.

If you read my previous blog, I mention a client who just recently moved their Oracle workloads from POWER to Intel.  Within months, they’ve had to buy over $5M in new licenses going from a simple standalone and a few 2-node clusters (all on the same servers) to an 8-node VMware based Oracle RAC cluster.  This environment is having daily stability issues significantly impacting their business.  Yes, their decision to standardize on a single platform has introduced complexity to the business costing them money, resources (exhausted & not having the proper skills to manage the complexity) that impacts their end-users.

The “Compromise” I mention to host SAP HANA on Intel is that everything has to be an asterisk by it – in other words a limitation or restriction – everything requires follow-up questions and research to ensure what the business wants to do, can be done. Here are some examples.
1) VMware vSphere 5.5 initially supported 1 VM per system which has now been increased to 4 VM’s, but with many qualifications.
a) Restricted to 2 & 4 socket Intel servers
1) VM’s are limited to a socket
2) 2 socket server ONLY supports 2 VM’s, 4 socket would be 4 x 1 sockets each
b) Only E5_v2, E5_v3, E7_v2 and E7_v3 chips are supported – NO Broadwell
c) Want to redeploy capacity for other? Appliances certified only for SoH or S4H
uses cannot be used for other purposes such as BW
d) Did I mention, those VM’s are also limited to 64 vCPU and 1 TB of memory each
e) If a VM needs more memory than what is attached to that socket? No problem, you have to add an additional socket and all of its memory – no sharing!
2) VMware vSphere 6.0 just recently went from 1 to 16 VM’s per system.
a) VM’s are still limited to a socket or 1/2 socket.
b) 1/2 socket isn’t as amazing as it sounds.  Since vSphere supports 2, 4 & 8 socket servers, there can be 16 x 1/2 socket VM’s.
c) What there cannot be, is any combination of VM’s >1 socket with 1/2 socket assigned. In other words, a VM cannot have 1.5 or 3.5 sockets. Any VM resource requirement above 1 socket requires the addition of an entire socket.  1.5 sockets would be 2 sockets.
d) Multi-node setups are NOT permitted …. at all!
e) VM’s larger than 2 sockets cannot use Ivy Bridge based systems, only Haswell or Broadwell chips – but ONLY on 4-socket servers.  Oh my gosh, this is making my head hurt!
f) If using an 8-socket system, it only supports a single production VM using Haswell ONLY processors.  NOT Ivy Bridge and NOT Broadwell!
g) VM’s are limited to 128 vCPU and 4 TB of memory
3) VMware vSphere 6.5 with SAP HANA SPS 12 only supports Intel Broadwell based systems. What if your HANA Appliance is based on Ivy-Bridge or Haswell processor technology? “Where is that Intel rep’s business card? Guess I’ll have to buy another one since I can’t upgrade these”
a) VM’s using >4 sockets are currently NOT supported with these Broadwell chips
b) Now, it gets better. I hope you are writing this down – For 2 OR 8 socket systems, the maximum VM size is 2 sockets.  Only a 4 socket system supports 1 VM with 4 sockets.
c) Same 1/2 socket restrictions as vSphere 6.0.
d) Servers with >8 sockets do NOT permit the use of VMware
e) If your VM requirements exceed 128 vCPU and 4 TB of memory, you must move it to a bare-metal system ….. Call me – I’ll put you on a POWER system where you can scale-up, scale-out without of this mess

Contrast all of these VMware + Intel limitations, restrictions, liabilities, qualification or simply said “Compromise” systems to the IBM Power System.

POWER8 servers run the POWER Hypervisor called PowerVM.  This Hypervisor and its suite of features deliver flexibility allowing all physical, all virtual and a combination of physical & virtual resource usage on each system. Even where there are VM limits such as 4 on the low-end system, that 4 could really be 423 VM’s.  I’m making a theoretical statement here to prove the point. Let’s use a 2 socket 24 core S824 server.  3 VM’s, each with 1 core (yes, I said core) for production usage and the 4th VM’s is really a Shared Processor Pool with 21 cores.  Those 21 cores support up to 20 VM’s per core or 420 VM’s. Any non-production use is permitted.

Each PowerVM VM supports up to 16 TB of memory and 144 cores.  VM size above 108 cores requires the use of SMT4 whereas <=108 cores permit SMT8.  Thus, 144 cores with SMT4 is 576 vCPU’s or 4.5X what Intel can do with 4X the memory footprint.  By the way, that 108 core VM would support 864 vCPU’s – just saying!  Note: I need to verify as the largest SMT8 VM may be 96 cores with only 768 vCPU.

Not only can we allocate physical cores to VM’s and NOT limited to 1/2 or full socket increments like Intel, but POWER systems granularity allows for adjustments at the vCPU level.

PowerVM supports scale-out and scale-up.  Then again, if you have heard or read about the Pfizer story for scale-out BW, you might rethink a literal scale-out approach. Read IBM’s Alfred Freudenberger’s blog on this subject at https://saponpower.wordpress.com/2016/05/26/update-sap-hana-support-for-vmware-ibm-power-systems-and-new-customer-testimonials/

While on the subject of BWoH/B4H, PowerVM supports 6 TB per VM whereas the vSphere 6.0 supports is 3 TB and the limitations increase from here.

Do you see why I choose to promote IBM Power vs Intel? When I walk into a client, the most valuable item I bring with me is my credibility.  HANA on Intel is a constant train wreck with constant changes & gotcha’s. Clients currently with HANA on Intel solutions or better yet, running ECC on Intel have options.  That option is to move to a HANA 2.0 environment using SUSE 12 or RedHat v7 Linux on POWER servers. Each server will host multiple VM’s with greater resiliency providing the business the flexibility desired from the critical business system that likely touches every part of the business.

Author: powertheenterprise

Client Executive & Enterprise Architect

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