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Siebel Application Object Manager Infrastructure

A Siebel Application Object Manager component is implemented as a multithreaded process on the Siebel Server. At runtime, a parent process starts one or more multithreaded processes, according to the Siebel Application Object Manager configuration.

Each Siebel Application Object Manager process can host multiple user sessions (as tasks), which in turn are implemented as threads within the process. These threads might be dedicated to particular user sessions, or they might serve as a pool that can be shared by multiple user sessions. (For each process, a few threads also start that are dedicated to performing core functions for the process.)

As more users log in, additional processes can be instantiated to host these users.

• In this chapter, the term thread is often used interchangeably with task, except when you are using thread pooling. For details, see Using Thread Pooling for Siebel Application Object Manager.
• The terms multithreaded server or MT server are alternative terms for multithreaded process (a process that supports multiple threads). For example, the names of the Siebel Application Object Manager parameters MaxMTServers and MinMTServers refer to multithreaded processes.

Siebel Application Object Manager components, which run in interactive mode, handle processing for Siebel Web Client sessions, in which the application user interface (UI) resides. The Siebel Application Object Manager task manages Siebel business objects and data objects and performs business logic for the client session.

Generally, each Siebel Application Object Manager task starts in response to a request from a Siebel Web Client running in a Web browser, and ends when the client disconnects.

Siebel Application Object Manager Communications with Other Modules

Each Siebel Application Object Manager task uses Siebel Server infrastructure capabilities to communicate with the Siebel Database, the Web server (through the SWSE), and other Siebel Enterprise Server components.

• Communication with the Siebel Database uses database connections. Database connections can also be managed and tuned for optimal performance. You can optionally configure connection pooling for database connections. For details on configuring database connection pooling, see Configuring Database Connection Pooling for Siebel Application Object Managers.
• Communication between the Siebel Connection Broker (SCBroker) and the Siebel Application Object Manager processes on the Siebel Internet Session Network Application Programming Interface (SISNAPI) same Siebel Server uses mechanisms internal to the operating system. SCBroker receives each SISNAPI connection request from the SWSE and forwards the connection request to a Siebel Application Object Manager multithreaded process. Once the request has been forwarded, subsequent requests for the same user session flow directly from SWSE to this Siebel Application Object Manager process.

  The request is forwarded using either a least-loaded or a round-robin algorithm, according to the setting of the SCBroker parameter ConnForwardAlgorithm.

  For more information about configuring SCBroker, see Siebel Deployment Planning Guide and Siebel System Administration Guide. See also the Siebel Installation Guide for the operating system you are using.

• Communication with the Siebel Web Server Extension uses SISNAPI, a messaging format that runs on top of the TCP/IP protocol. SISNAPI connections can be configured to use encryption and authentication based on Secure Sockets Layer (SSL). For details on tuning SISNAPI communications, see Configuring SISNAPI Connection Pooling for Siebel Application Object Manager.
• Communication with other Siebel Enterprise Server components (including other Siebel Servers) also uses SISNAPI, going through Server Request Broker (SRBroker). For more information about tuning SRBroker, see Tuning Server Request Broker (SRBroker).

About Tuning the Siebel Application Object Manager

Tuning activities directly or indirectly applicable to Siebel Application Object Manager components might involve any or all of the following:

• Configuring your system initially using Siebel Configuration Wizards. These wizards are described in the Siebel Installation Guide for the operating system you are using.
• Using the Siebel Server Manager (GUI or command-line version) to tune parameters for the Enterprise Server, the Siebel Server, or the Siebel Application Object Manager component. These parameters are stored in the siebns.dat file in a directory on the Siebel Gateway Name Server.
• Selectively enabling component groups and components on each Siebel Server. Only enable the component groups and components you need.
• Tuning parameters in the eapps.cfg file on the Siebel Web Server Extension. This file is located in the bin subdirectory of the Siebel Web Server Extension installation directory, on the Web server computer. You configure the SWSE initially using configuration wizards, as described in the Siebel Installation Guide for the operating system you are using.

Some other chapters in this book discuss Siebel Application Object Manager tuning that relates to using other modules, such as Siebel Communications Server or Siebel Configurator.