Sizing

The size of the hardware and database is influenced by both business aspects and technological aspects. This means that the number of users using the various application components and the data load they put on the network must be taken into account.

With the help of SAP Standard Application Benchmark results at www.sap.com/benchmark, statements can be made as to CPU consumption and memory consumption of particular software components.

For sizing we have identified three different and independent sizing models that have different advantages and disadvantages. The first two, user-based sizing and throughput-based sizing, have been implemented in the Quick Sizer.

User-based sizing
We defined three types of active users who work with the system to a different degree. Merely counting the users can be done quite easily. The disadvantage is that this estimation is quite rough as it says very little about the actual throughput these users produce.

Throughput-based sizing
This model is quite thorough because it relies on actual or on actually expected throughput. However, this model relies on a number of assumptions in business terms (e.g. number of order line items per year) that need to be cross-checked against the individual installation.

Customer Performance Test
The according tests are done in a customer system with customer data. The disadvantage is that conducting these tests requires considerable time and money. For further information please refer to the white paper Carrying Out Customer Performance Tests.

Quick Sizer is a web-based tool designed to make the sizing of SAP Applications easier and faster. It has been developed by SAP in close cooperation with all platform partners and is free of cost.

With Quick Sizer you can translate business requirements into technical requirements. Simply fill in the online questionnaire, an up-to-date survey that is based on business-oriented figures. The results you obtain can help you select an economically balanced system that matches your company's business goals. This is especially useful for initial budget planning.

You can find in the sizing decision tree more information about the right usage of the different sizing methods and tools. If you want to conduct a HANA sizing and you are not sure which tool to use or which SAP note to apply, it’s highly recommended to have a look at this document.

The term “greenfield sizing” is mostly used in the context of new implementations without or with only little experience with SAP software. It refers to the process of finding out what the main load drivers are and attaching some sizing value to them. Very often, this is done in the early phases of a project where actual business processes and required data volumes are not available in detail. So greenfield has two meanings: new to SAP and/or early in the project. In greenfield sizing, standard tools, such as Quick Sizer and sizing guidelines are used.

Quick Sizer calculates memory, CPU, disk, and I/O resources based on throughput and number of concurrently active users. Watch this video for an introduction to Quick Sizer.

Complete the following steps:

1. . Access the Quick Sizer tool

Use the SAP HANA version if you want to size an SAP HANA database, or the classic version if you want to size a non-SAP HANA database.

1. . Create a sizing project

Input your customer scenario data into Quick Sizer and it will display the results.

1. . Check for sample configurations

Find the appropriate hardware configuration(s) on SAP Standard Application Benchmarks or on the Certified and Supported SAP HANA Hardware Directory

1. . Provide the project name to your hardware vendor, who will then propose an appropriate hardware configuration.
2. . If you are unable to find the right sizing for your SAP product in the Quick Sizer tool, consult the sizing guidelines.

Typically, in an expert sizing, more profound analyses are performed. Very often, this means exploring some business processes in more detail, both on functional and technical level. There are no standard tools available to conduct expert sizing. There are very different use cases when an expert sizing is required. In most of the cases, an expert sizing is not trivial and requires a lot of SAP expertise.

For an expert sizing, the customer has to perform the following steps:

1. . Identify the most important queries/apps/scenarios
2. . Identify, how they will be used, e.g. filter criteria, authorizations
3. . Run these queries/apps/scenarios on representative test data (quality of test data and quantity of test data). Ideally, on a recent copy of the production data. 
4. . Measure resource consumption (CPU/memory) and response times
5. . Perform a forecast calculation based on the expected usage of the queries/apps/scenarios

Please refer to this presentation to get more information what expert sizing can include.

At SAP, expert sizings are typically covered by Consulting and / or Support. Please check this SCN page for additional information.