SAP HARDWARE SIZING
It is used to measure/determine the hardware i.e, required for SAP Systems to be implemented.
SAP provides QUICK SIZER Tool to calculate the Skeleton Model Sizing.
The Quick sizer is a tool jointly developed by SAP and its hardware partners to help customers get an idea about initial sizing. It is FREE of Cost.
SIZING means determining the hardware requirements of an SAP System such as Network Bandwidth, physical memory, CPU power and I/O capacity. The Sizing is based on the SAP Standard Bench Marks. It is also referred as T-Shirt Sizing and sizing categories falls in S,M,L,XL and XXL etc.
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 consideration.
Sizing is used to determine the following-:
- High Availability [Mirroring, Clustering, SAN, RAID, Disaster Recovery Servers] major impact on sizing.
- Storage requirements in terms if disk.
- Memory requirements
- Processor requirements
- Network Topology
- Backup Strategy
- Peak and Off peak hours [To determine the load]
- Specify the Deploy-able components and applications modules [SD,MM,FI,CO,HR,QM,PM,PS etc]
SIZING is performed by using the URL -: www.service.sap.com/sizing
The sizing is based on 2 aspects-:
- User-Based
- Through Put Based
- User Based Sizing-: The sizing is based on users, SAP segregates users into 3 types which are based on the dialog steps.
Dialog Step -: It is a mouse click, keyboard stroke {ENTER}, Screen change etc.
Each dialog step is processed by process id in the system.
- Low User -: Low user handles around 0-480 dialog steps per week.
480- dialog steps/8 hours & 5 days i.e, 40 hours
480 dialog steps are generated in 40 hours
Each dialog step takes (40 hours * 60 mins)/480 = 5 mins or 300 secs
- Medium User -: Medium user handles around 480-4800 dialog steps per week
4800 dialog steps/8 hours * 5 days i.e, 40 hours
4800 dialog steps are generated in 40 hours.
Each dialog step takes 40 hours * 60 mins/4800 = 0.5mins or 30 secs
- High User --: High User handles 4800 to 14400 dialog steps per weak.
14400 dialog steps/8 hours * 5 days i.e, 40 hours
14400 dialog steps are generated in 40 hours.
Each dialog step takes 40 hours * 60 mins/14400 = 10 secs
The disadvantage of user based sizing is that this estimation is quite rough as it says very little about the actual throughput (LOAD) these users produce.
NOTE-: This is used for fresh implementation where the exact number of documents are unknown.
If the documents size or number is known then object based throughout sizing is preferred.
2. Throughput Sizing --:
It is based on transaction volume and mostly during upgrades [Functional expertise is required to identify the transactions such as number of sales orders, purchase orders, invoices, billing, shipping, delivery etc]
It gives you optimal results only when exact volume of transactions are known.
NOTE-: User based sizing is recommended during implementation because the exact volume of transactions are not known and the number of users are determined on the early stages of implementation.
This is used during upgrading or resizing or delta sizing or during Add-on
Save the Sizing and click on calculate the result. The sizing output is displayed as follows-:
- CPU category --: Specifies the size of CPU category [S,M,L,XL and XXL]
- Numbers of SAPS [Unit of measure CPU(processors)]
- Memory required in MB/GB
- Disk Category --: Specifies the size of the Disk Category [S,M,L,XL, and XXL]
- Disk storage in MG/GB
SAPS:SAP Application Benchmark for Performance Standards
In short, SAP Application Performance Standards (SAPS) describe the throughput power of a given hardware configuration.
It is a hardware independent unit that is derived from the business processes of SD [SALES and DISTRIBUTION] standard application benchmark.
In detail, 100 SAPS are 2000 fully business processed SD order line items per hour or in more technical terms, 2400 SAP transactions or 6000 dialog steps (screen changes) per hour.
In SAP enviornment you can use the SAPS value of given hardware configurations to compare their throughput capabilities with SAP Software.
These SAPS are used to determine the processor speed and number of processors required for the company.
What is the output Sizing?
Storage, memory and CPU in terms of SAPS [It is a unit to measure CPU which is based on SD transactions] i.e, 2000 line items of SD or 2400 transactions or for every 6000 dialog steps per hour 100 SAPS are required.
Hardware vendors measure/convert the SAPS into number of CPU based on processor speed.
Example -: An IBM P Series Machine generates around 800-1000 SAPS/hour
Analyzing the sizing results and define the final sizing report.
The sizing is a Skeleton report which is measured only for SAP Users. We need to consider the following before final sizing decisions are made-:
- Operating System
- Database
- Virtual Memory
- Interfaces [SMS, FAX, MOBILE (PDA, HANDHELD)]
- Printers [Remote/front end printing will be expensive]
- Third party tools [Background job schedulers, printing tools, vertex tool (TAX update)] and connectivity with Banks for online payment.
- Connectivity with SAP and Non-SAP systems. [Weigh Bridge Management, Bio-metric Systems]
- Backup tools like VERITAS etc
- Legacy Data
- Future growth of company [Local and growth of users for at least 3 years]
Considering the above the sizing may grows or double i.e, increase by 100%
Example --: 4 CPU's are required during normal sizing which grows by 8 CPU's and similarly memory doubles, storage is not a major bottleneck nowadays, but ensures that the hardware i.e, scalable.
The sizing result is provided to the vendors to call the quotations for supplying the hardware, based on the OS,DB, maintenance support [Custom orientation and AMC charges]
Recommendation -:
Run the SAP Quicksizer tool to get the initial skeleton model but it is really important to consult an authorized Hardware Vendor to check the exact details about the different servers.
Regards
Samar
