Sizing BPC on HANA
Sizing BPC on HANA is a two-steps process. You first have to size the underlying BW on HANA, then add the part dedicated for BPC components.
First, if you install a BW system from scratch, this comes with some basic memory requirements, mainly:
- Row store and column store system tables
- Memory for caches
- Memory acquired by services like name server, statistics server, etc.
Measurements show that such an “empty” BW system already utilizes ~50GB of memory on the server.
Here are below the exact formulas to be used for this sizing exercise:
RAM = ((Source data footprint – 60GB) * 2 / 4 * c1) + 90 GB
RAM = (( colstore tables footprint * 2 / 4 + rowstore tables footprint / 1.5 ) * c1) + 50 GB
Where c1 = compression coefficient, take 1 if you don’t know.
Then you need to follow the BPC sizing guide to evaluate the added needed BPC-only part:
The BPC sizing guide restricts on the size of those data which are subject to planning (i.e. planning InfoCubes + space for materializing the planned results, as well as metadata). This is what I would refer to as “business data”. Note that NO business data whatsoever is included at all in the estimated 50GB of an “empty” BW system. Then, the BW sizing is for the BW component only. If you do not have application data in BW, the lower limit is defined by the application server, which consumes 50GB.
If you take into example a CAT2 BPC system, the application part is then defined by the BPC sizing, which adds additional an 45GB. Hence, you need, at minima, 95GB for your BW+BPC.