Saturday, July 10, 2010

Picking an SAP Business Warehouse Accelerator (BWA) Hardware Provider

My team recently completed an evaluation of the SAP Business Warehouse Accelerator (BWA) product from three different vendors and I felt the insights gleamed during this process were worth sharing. First, if you are not an SAP customer and even more specifically an SAP Business Warehouse customer, you probably have never heard of the SAP BWA offering. The BWA is SAP’s “in memory database” solution designed to speed up complex analytical queries submitted by information workers. The way this works is that data is moved from the SAP BW OLAP database into the BWA columnar database located in the BWA RAM during a load and fill phase. End user request are directed to the BWA which provides much faster response time than the traditional OLAP database located on regular spinning disks. SAP markets the BWA as an “appliance” which is a complete misnomer. Here is what the BWA truly consists of:

Hardware

A dedicated infrastructure committed solely to the BWA workload. The infrastructure consists of dedicated disks (in most cases in the form of a dedicated SAN chassis) and a blade chassis and associated blades. The BWA blades are delivered as a SUSE Linux cluster with one hot spare server blade. The term dedicated is very important here. SAP is very strict on what they support from a hardware perspective. They have certified specific solutions from various different hardware vendors such as HP, Dell, IBM and Cisco with all of these solutions required to be solely dedicated to the BWA environment. Already have a SAN with space? Too bad, you can’t use it. Already have a data center full of IBM or HP blade chassis with room to handle the additional capacity of BWA? So sorry, you can’t use it. The entire technology solution is required by SAP to be totally segmented from you other data center workloads. A dedicated subnet is also required between the BWA and the message service associated with your BW application server logon group. The dedicated networking can take the form of a VLAN riding across your existing data center network. Not only can you not share the BWA infrastructure among other data center workloads, you cant share the infrastructure between your BWA test and BWA production environments. So you bought a BWA solution with a dedicated SAN and blade server chasis and you want to put a couple of BWA test blades in the same chassis as your production blades and leverage the same SAN as production? Sorry, that is not supported. Simply take the hardware quote you got for all that dedicated infrastructure for BWA production and multiply it times two and thats your cost for a test and production SAP BWA environment. SAP does not support any intermingling of your test and production BWA infrastructure. The notion here that SAP does not “support” a shared infrastructure between BWA test and BWA production is important. This does not mean a shared infrastructure won’t work, it will work just fine. The gotcha is however that if you do encounter performance problems on the BWA and you contact SAP for support and they discover you have shared the test and production infrastructures, you will politely be asked to separate those environments before you receive any assistance. This of course goes directly against the movement towards efficient and virtualized data centers. SAP is being slow to accept alternative solutions to the BWA product delivery model, primarily because of what it is selling with the BWA which is performance. The BWA software is not cheap but it really does deliver amazing performance results. Unlike other SAP products like CRM where what SAP is selling is streamlined and efficient business processes, with the BWA SAP is selling a promise of enhanced query performance and thus faster decision support. Regardless, it feels like this promise could be fulfilled in a more elegant fashion that does not require IT managers to invest in infrastructure when they may already have computing capacity.

Software

SAP licenses the BWA software “by the blade”. This is an unfortunate choice of terminology on SAP’s part because it adds to the confusion that exists in the market about the BWA product. By the term blade here SAP is NOT refereeing to the physical server blades you have purchased for your blade chassis. SAP defines a BWA “blade” as a logical unit consisting of 4 GB of RAM. When you size your specific BWA environment, you will be asked to run some reports in your existing BW system and provide those to the hardware providers you have chosen to work with. Each hardware provider who offers a SAP certified BWA “architecture” has a group who can use the BW report information to help you size your BWA environment in terms of the amount of RAM you will need to “accelerate” your specific quantity of data. The minimum BWA size is four blades or 16GB of RAM. So to determine your software costs, you can divide your overall BWA RAM size by four and multiply the result by the SAP price per blade. Currently, SAP does not charge for the BWA test environment software, only production.

What we found when looking at different vendors for the SAP BWA hardware “appliance” is that even though SAP has a strict certification process for various combinations of blade server chassis and storage arrays; you will still get inconsistent answers from vendors on what is and is not supported from SAP. The big area we saw this in was whether you can share test and production infrastructure. Some vendors said yes, others said no. The final word came from SAP who clearly states a shared infrastructure is not supported (again, not that it won’t work). Another dimension to consider when talking to hardware vendors is how well defined you feel their respective SAP BWA product is. For example, some of the vendors we meet with seemed to be trying to put together an offering based on their latest offering initiatives “on the fly” stating they would simply need to check with SAP on cretin configurations. Keep in mind, SAP has a stringent certification process around the BWA “appliance” offering. It should be very straight forward, a given combination of storage and servers are either certified or not, period. You should also get a comfort level around the particular hardware providers service offering as it relates to the SAP BWA implementation. The “appliance” is sold as turnkey meaning that you as a customer cannot install it yourself. In addition to certifying a hardware combination, a vendor also certifies a service offering for installing and configuring the BWA solution. Because you have to use this install service, it is important to ask and understand how a vendor will deliver the service. Do they have a certified team or will the work be contracted to a third party? Again, the definition of the vendors install service should be clear and straight forward without requiring a lot of back and forth and “checking”.