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

ITS Installation Sizing

An Internet Transaction Server (ITS) installation typically consists of one or more servers running WGate and one or more servers running AGate.

When sizing an ITS installation, you should take the following into consideration:

Do you have a single host installation or a dual host installation?

The installation type depends on whether you are setting up development and test systems or production systems:

With a single host installation, WGate and AGate run on the same machine

This is sufficient for development and test systems.

With a dual host installation, WGate and AGate run on separate machines

For security reasons, you should always use this installation type for production systems.

For further information, see ITS Installation Options.

Performance limiting factors such as:

CPU resources

Each request/response cycle from the Web browser to the R/3 System via the ITS uses CPU resources.

Memory allocation

The amount of memory needed depends on the number of users concurrently accessing the system.

Disk space

This depends on the number of ITS files stored on the host file system.

For further information, see Performance Limiting Factors.

HTTP or HTTPS

If you are encrypting (and hence decrypting) all messages sent from the Web browser using HTTPS (secure HTTP), this imposes a higher load on the Web server.

Which services do you intend to make available to users?

When you have decided which services you want to offer, you need to determine:

Which services impose a continuous load
Which services impose a load only at certain times

The total number of concurrently active users (or hits per second) for all services

Although it is difficult to work out an exact number and there are several strategies that you could use to find this out, you can determine the probable maximum figure for your system by following the procedure recommended here.

See Calculating Active Users.

Network configuration

You need to find the right network configuration between the different server components and between the server and clients.

See Performance Limiting Factors.

Web server settings

The required Web server settings depend on the Web server you are using.

See Making Web Server Settings.

ITS size

When you have looked at the hardware installation requirements and determined the total number of active users likely for your system, you can work out the required ITS size.

See Sizing the ITS.

R/3 size

When sizing the ITS, you also need to be aware of the size of the underlying R/3 System, since every ITS user could also be a concurrent R/3 user.

See Sizing the R/3 System.