Ron Schmerbauch wrote this week’s blog on SAP. Ron is a member of the IBM i SAP Development Support team in the Rochester (Minn.) development lab.
With the announcement of POWER7 came another record setting result on IBM i for the SAP Business Intelligence Mixed Load (BI-MXL) Standard Application Benchmark. The key figure of this benchmark is the number of query navigation steps/hour, a measurement of overall throughput. In October 2009, we were able to run 154,447 query navigation steps/hour on eight POWER6 processor cores and IBM i 6.1. Our latest result was achieved with the POWER7 processor-based Power 750 Express where we hit 241,526 query navigation steps/hour using eight cores. That’s a 56-percent improvement from POWER6 to POWER7 with the same number of cores!
The POWER7 supports SMT4 (four threads of execution within each core), where the POWER6 supported only SMT2 (two threads within each core). This is important for application server architectures like SAP’s where many users on PC clients are sharing a set of application server jobs on IBM i. Our results show that more users can simultaneously get work through the system by using POWER7.
Although POWER7 offers a benefit over older hardware, the star of the SAP BI benchmark is DB2 for IBM i. When the new DB2 for IBM i SQL Query Engine (SQE) was being developed several years ago, SAP BI experts visited Rochester to discuss and review the designs because SAP’s BI application was heavily using the type of complex queries that SQE was hoping to excel with. Since the introduction of SQE, IBM i has been publishing leading SAP Business Warehouse (BW) and BI benchmarks.
The current and most challenging workload of all has been BI-MXL.SAP designed this benchmark specifically to defeat the high degree of tuning measures that are usually implemented in benchmarking performance environments. In older SAP BI workloads, the dataset was static and extreme tuning could be applied to get fast responses. But BI-MXL requires that both queries and data upload/updates are executed simultaneously. This makes the data that’s being queried in the system dynamic, just like in a real customer environment, and the DB2 for i engine has to keep coming up with the right answers and it has to do it quickly.
Although the SAP application server engine uses the same core set of source code for all SAP platforms, the SAP BI application layer implementation is allowed by SAP to take advantage of DB2 for i specific features. For SAP BI on i, this means SAP supports the use of DB2 on i features like Encoded Vector Indexes (EVIs), Materialized Query Tables (MQTs), Lookahead Predicate Generation (LPG) optimization and partitioned table support. EVIs are included in SAP’s automatic indexing strategy for DB2 on i, and LPG is used by default within the optimizer. MQTs and partitioned tables are features that SAP can recognize within the application if you desire to use them.
The i and AIX operating systems share a common code base, compiler and C/C++ runtime for the SAP application server engine. Additional IBM Power Systems leadership results with POWER7 on the SAP Sales and Distribution (SD) Standard Application benchmark showed a high degree of scalability in the Power 750 family with up to 32 cores. Because of the commonality in the core SAP application server engine executables, i and AIX are able to share a common sizing matrix to determine which Power System model would be suitable for a given SAP workload requirement.
Look for more SAP BI-MXL publishes on IBM i with POWER7 in the coming months – with even better results on the next version of the IBM i OS.