Sizing the ITS (SAP Library - ITS Tuning and Troubleshooting Guide)

Sizing the ITS

Use

You use this procedure to size the Internet Transaction Server (ITS) according to the maximum number of active users.

The sizing recommendations specified here are based on performance and benchmark tests as well as initial observations at customer sites, so you should regard them as guidelines only.

Please also remember that:

These are minimal requirements

The more CPU and main memory are available, the better the performance of the ITS.

ITS response times and throughput also depend on the response time of the R/3 System

If your ITS is producing high response times, you should first examine the SAP GUI response times on the R/3 side.

Procedure

Check minimum installation requirements for hardware.

Determine the ITS size.

Check Minimum Installation Requirements

The tables below specify the minimum hardware you need to run the ITS, depending on whether you are performing a single host installation or a dual host installation. Please remember that you should always use a dual host installation for production systems.

Hardware Requirements for Single Host Installation

Component	Requirement
Hardware	Intel Pentium compatible architecture
Backup (optional)	Either over network or tape drive
Hard disk	1 GB
Memory (RAM)	128 MB

Hardware Requirements for Dual Host Installation

Component	Requirement
Hardware	Intel Pentium compatible architecture
Backup (optional)	Either over network or tape drive
Hard disk	2 x 1 GB
Memory (RAM)	2 x 128 MB

The number of processors required depends on the number of concurrent requests made to the R/3 System.

Determine ITS Size

You determine the size of your ITS according to the calculated number of active users.

Number of Active Users	Recommended Configuration	Requests per second	Requests per day
Personal ITS	1-processor Pentium III Xeon 500 MHz, 256 KB L2 cache, 64 MB main memory, 1 GB disk.
0 – 250	1-processor Pentium III Xeon 700 MHz, 256 KB L2 cache, 256 MB main memory, 10 GB disk.	5	432,000
251 – 500	1-processor Pentium III Xeon 700 MHz, 256 KB L2 cache, 512 MB main memory, 10 GB disk.	10	864,000
501 – 1,000	2-processor Pentium III Xeon 700 MHz, 1 MB L2 cache, 1 GB main memory, 10 GB disk.	20	1,728,000
1,001 – 3,000	4-processor Pentium III Xeon 700 MHz, 2 MB L2 cache, 2 GB main memory, 10 GB disk.	50	4,320,000
> 3,000	Multiple ITS.