Initial IT environment
Coop Group runs a full suite of SAP applications to manage its business. A few years ago, the company had successfully consolidated around 300 SAP application servers and databases from dedicated systems to the IBM Power Systems platform, using advanced IBM PowerVM virtualization technology. Coop Group has been running its SAP application servers and Oracle Database instances on IBM AIX ever since. Having initially migrated to IBM Power 795 servers, Coop Group now runs its SAP landscape on four IBM Power System E880 servers with IBM POWER8® processors. Using the IBM Power Enterprise Pool feature, to maximize efficiency the company can flexibly shift workloads with the required processing and memory capacities between all four servers.
The application landscape at Coop Group comprises SAP for Retail with SAP ERP, SAP Customer Activity Repository, SAP ERP Human Capital Management, SAP Supplier Relationship Management, SAP Customer Relationship Management, SAP Forecasting and Replenishment for Retail, SAP Business Warehouse, and SAP Global Trade Services, as well as the SAP Hybris e-commerce solution.
To accelerate data analytics, Coop Group had implemented an SAP Business Warehouse Accelerator solution based on 768 x86 processor cores with a total memory of 3 TB, running 64 separate operating system instances.
For its SAP Customer Activity Repository, Coop Group had deployed a SAP HANA database. The company was running its large environment on a scale-out appliance solution without virtualization. To handle its 3 TB SAP HANA database, the company operated an eight-node cluster with 320 x86 cores in total.
The total workload was becoming a real challenge for the systems running the SAP Customer Activity Repository application. Christoph Kalt comments: “In the past, we had to cut down the volume of data we used for SAP Customer Activity Repository analytics because of the limitations of the platform. This made it difficult to gain a near real-time overview of inventory movement.”
Technical solution
When Coop Group looked at expanding its SAP HANA environments to drive its transformational strategy, it decided to simplify the underlying server architecture, and standardize its SAP infrastructure landscape across all solutions and applications. This meant moving its SAP HANA databases to IBM Power Systems servers.
Thomas Vielhauer remarks: “Knowing the reliability and low administration requirements of the IBM Power Systems platform from previous experience with our major SAP applications and databases, we were curious to see how SAP HANA would perform on high-performance POWER8 processor-based servers.”
Coop Group worked closely with teams from IBM and SAP to migrate its mission-critical SAP Customer Activity Repository and SAP Business Warehouse applications to SAP HANA running on IBM Power System E880 servers.
Christoph Kalt recalls: “We were able to complete the implementation and migration extremely quickly, in less than two months. Everything went very smoothly, and we were glad to have the support of both IBM and SAP during the migration of such large, business-critical systems.”
Server architecture
Sizing the new servers to run several large SAP HANA databases together with the SAP application servers, Coop Group deployed four IBM Power System E880 servers with IBM POWER8 processors. The servers have been installed in two separate data centers to provide redundancy at both locations. Because the data centers are 130 km apart, all data is synchronized between the two locations via asynchronous storage mirroring. A manual failover procedure ensures business continuity in the event of disaster at one of the sites.
The company runs its SAP HANA databases on IBM Power Systems servers with SUSE Linux Enterprise Server for SAP Applications. This is an optimized operating system platform, validated and certified by SAP. SAP and SUSE collaborate on its development to achieve the best possible performance for mission-critical SAP applications. The optimizations include a kernel tuning option for improved page cache performance, and simplified installation procedures for SAP HANA to speed up new deployments. Additionally, SUSE Linux Enterprise Server for SAP Applications has a dedicated update channel to deliver patches, fixes and updates to features specifically for SAP applications. To reduce the business risk further, the solution also offers access to seamless, integrated priority support from SAP and SUSE.
Christoph Kalt elaborates: “Because of our extensive experience with fully virtualized IBM Power Systems running IBM AIX, we already knew how the platform works. So we could build on our knowledge of concepts and configurations from our IBM AIX environment, and use this experience for the new SAP HANA solution with SUSE Linux Enterprise Server for SAP Applications running on IBM POWER processors. This helped us to get started quickly, and facilitated the streamlining of operations and management processes.”
Thomas Vielhauer comments: “Having all of our SAP applications—those running on SAP HANA and those on traditional databases—on a single server platform has standardized our IT infrastructure. This helped to significantly reduce the time spent on management and maintenance.”
Taking advantage of the advanced IBM PowerVM virtualization capabilities, the team set up dedicated logical partitions (LPARs) for the SAP HANA databases to ensure optimal performance at all times. The two largest SAP HANA databases run on LPARs with 96 IBM POWER8 processor cores, configured in dedicated-donating mode.
For the application servers, Coop Group configured shared processor pools on each machine. When the load is low, the two large partitions also donate spare processing capacity to the shared pool. Combining dedicated and shared logical partitions enables the company to use the available computing and memory capacity very flexibly. These dynamic logical partitions can use more processor cores or memory out of the shared resource pool when needed, without manual performance tuning. IBM PowerVM automatically assigns available and unused server resources to the logical partitions with the highest load, helping to boost performance and minimize manual administration requirements.
Increasing the flexibility further, Coop Group can easily move active logical partitions between the two servers at each location without disruption of applications or databases for staff, users or customers. The IBM PowerVM Live Partition Mobility (LPM) feature supports smooth system maintenance, as the team can avoid most planned downtime. In combination with IBM Power Systems Capacity on Demand, the company can temporarily increase the number of processor cores and memory to cover maintenance or other activities, and run more systems than usual on one of its IBM Power System E880 servers.
Christoph Kalt comments: “The advanced virtualization capabilities and easy scalability of the IBM Power Systems platform was a key factor that went into our decision to move our SAP HANA environment.”
At the moment, Coop Group keeps the logical partitions running SAP HANA with SUSE Linux Enterprise Server for SAP Applications and the partitions running the IBM AIX operating system on separate physical servers. If the company ever wanted to consolidate its infrastructure more comprehensively, Coop Group could also mix logical partitions with different operating systems (such as IBM AIX and Linux) on a single IBM Power System E880 server.
SAP HANA on IBM Power Systems architecture
Leveraging the flexibility and performance of IBM Power Systems, Coop Group implemented its SAP HANA applications in a SAP HANA Tailored Datacenter Integration (TDI) configuration. The fully virtualized environments benefit from all of the built-in reliability and performance features of the IBM Power System platform.
In close collaboration, Coop Group, IBM and SAP migrated the company’s SAP Business Warehouse to SAP HANA running on IBM Power Systems.
Coop Group also migrated its SAP Customer Activity Repository to SAP HANA on IBM Power Systems. Christoph Kalt explains: “Partitioning some tables in a SAP HANA cluster can be tricky, and because a master node and a backup node were required, we could not use the full capacity of the solution. By moving to IBM Power Systems, we wanted to reduce unused resources and avoid paying for capacity that we could not really use.”
Thomas Vielhauer confirms: “To support the long-term success of our business strategy, extensibility was one of the main drivers for moving our SAP Customer Activity Repository application to SAP HANA. We could not simply add a new node to our existing cluster, because the vendor no longer offered exactly the same server hardware. Since mixing different nodes was also not an option, we would have had to replace the entire cluster just to add extra capacity—not a very cost-efficient proposition. Being able to activate more processor cores and memory whenever needed over the full lifetime of the servers helps us to protect our investment much more effectively. This makes IBM Power Systems the preferred platform for our rapidly expanding SAP HANA environment.”
With IBM PowerVM, Coop Group can deploy larger virtual machines to meet the company’s business requirements. A non-disruptive growth path for the systems increases overall availability and reduces business risk. Installing fewer physical servers reduces the manual configuration workload—including routine tasks such as cabling, connecting power supplies and setting up network equipment.