SGEN in detail

Information about the SAP Load Generator (SGEN)

Overview

With transaction SGEN, you can generate ABAP loads in your SAP system. This includes the load generation for specific software components/packages, the generation for changed components after a system upgrade, and the regeneration of previously generated loads. You can also resume or repeat previous SGEN runs, include specific transport requests, and generate Business Server Page applications (BSP applications) and Web Dynpros.

The initial SGEN screen gives you options regarding the following:

• Tasks of the generation

• Selection of system components (if you select a component specific task)

• Selection of software packages (if you need to include specific packages)

• Selection of transport requests (if you need to include transport requests)

Depending on the selected task/s, on subsequent screens, you can select system components, packages, and/or transport requests.

You can start the generation on the Job Monitor screen. In addition, this screen gives you information about generation jobs that may have already run or are current such as, for example, predictions regarding the duration of the generation.

Note: If you want to regenerate loads, make sure that there is enough space available in your database. The space required can be several hundred MB. Generation over all components requires around 2 GB of free space.

Procedure

1. Select Task of the Generation.

On the initial screen of transaction SGEN, you can select the tasks that suit the purpose of the generation:

• Generate all objects of selected software components

Choose this strategy if you want to generate the loads of all objects of certain software components. This may be the case, for example, if your system has been reinstalled. Here, the loads required for operation are not yet available and must be regenerated.

After selecting this task, the Selection by software components screen appears. Here, you can choose the objects to be generated by selecting specific software components. Use the pushbutton to select the software components you require.

• Generate all Objects of Selected Packages

For a more fine-tuned selection of desired loads you can also specify software packages whose objects shall be regenerated.
After selecting this task, the Selection by software packages screen appears. Here, you can include specific packages to the generation. Since packages are defined in a tree structure, you can choose via a push button on the ALV grid to also include the complete subtree (all subpackages on all hierarchical levels below the given package). For example, if you select the packages BASIS, the inclusion of the subtree will usually (depending on the system) add several thousand additional packages. The number of subpackages is given just right to the pushbutton (after the selection is made); you can see the complete list of the subpackages by clicking on this number.
The red/green light indicates if a specified package is found in the system. Green lighted packages are included in the generation (although they need not have objects to be generated), while red lighted packages are unknown (due to the installation base or just mistyping) and will be ignored. You can use the F4 search help to find installed software packages.

Note: Duplicate entries of packages (directly or indirectly through subtree selection) do not negatively influence the generation: Duplicate packages will be filtered and just processed once.

• Regenerate after a SAP System Upgrade

After an upgrade, you have to regenerate the load of the ABAP objects in your SAP system. Here, the following is required:

• • The runtime of the generation process in transaction SGEN must be as short as possible.

• • The storage space required by the ABAP loads in the database must not be too large.

• • The generation effort on the part of the user must be as small as possible.

The following generation set takes the above requirements into account. It consists of all objects with loads, which were available in your system before the upgrade (that is, objects that you already used before the upgrade), and all objects that were redelivered in the release interval between start release and target release of your upgrade. The names of the objects that were generated before the upgrade were stored in the REPLIST file in the current directory of your system during the upgrade (profile parameter DIR_HOME).

After selecting this task, the Selection by software components screen appears. In the standard setting, all software components are selected. You are able to restrict the amount of objects to be generated by deselecting software components. Use the pushbutton to deselect the software components you want to ignore.

• Regenerate the Objects of the Last Run

This task is suitable, for example, in the following cases:

• • The generation of objects of the generation set that was used in the previous run was terminated and you want to regenerate the remaining objects.

• • You want to regenerate all objects of the generation set that was used in the previous run.

After selecting this task, the following modes are available:

• • Mode ALL
    All objects of the generation set used in the previous run of transaction SGEN are generated.

• • Mode RESUME
    The generation set of the previous run of transaction SGEN is used. Only those objects that were not generated in the previous run or whose generation was terminated due to a system error are generated.

• • If entries in the SGEN queue still exist (table GENSETM), this task is selected by default. Deselecting the task will result in a new SGEN queue discarding the old entries, while keeping it will add the newly selected generation tasks to the existing queue.

• Regenerate Existing Loads

This task allows you to regenerate all ABAP loads and invalidated loads that exist in your SAP system, and to generate loads for objects of a Support Package queue. The following modes are available:

• • Mode ALL: Generate all objects with existing load

• • Mode INVALID: Generate only objects with invalidated load

The load of an object becomes invalidated if changes have been made to the object or to the objects used by this object, since the moment the load was generated. Examples of such objects are includes and tables. This may occur by importing a Support Package SPAM or a kernel patch.

If you want to generate loads for objects of a Support Package queue, start the task after importing the queue. The task determines the generation set using the invalidated loads in the system. In contrast to the Generate objects of transport requests task, this task also considers ABAP loads that were invalidated by modified Dictionary (DDIC) objects.

• Generate Objects of Transport Requests

This task enables you to generate loads for objects included in transport requests. You can use it, for example, to include customer developed objects into the generation.

After selecting this task, a screen to select the transport requests appears. You can add single transport requests, remove selected transport requests, and import a list of transport requests using a file on the frontend. For details on the file format use the info button on the Import file screen. After importing a file, an analysis of the data is shown.

Note: Duplicate transport requests will be filtered, and invalid entries in the file will be marked erroneous and will not be added to the transport request list.

• Generation of BSP Applications

This task enables you to generate BSP applications of selected software components.

Each Business Server Page is realized technically through an ABAP object class. When BSP applications are generated, these classes and their ABAP loads are generated. BSP applications are not included in the generation sets of the Generate all objects of selected software components, Regenerate after an SAP system upgrade and Regenerate all existing loads tasks, since they are optional. You can use this task to deal with these.

After selecting this task, the Selection by software components screen appears. In the standard setting, all software components are selected. You are able to restrict the amount of objects to be generated by deselecting software components. Use the pushbutton to deselect the software components you want to ignore.

If you interrupt the generation of BSP applications before it has finished, or if the system terminates generation, the Regenerate the objects of the last run task allows you to resume the generation.

• Generation of Web Dynpros

This task enables you to generate Web Dynpros of selected software components, similar to the BSP applications. Web Dynpros are not included in the generation sets of the Generate all objects of selected software components, Regenerate after an SAP system upgrade and Regenerate all existing loads tasks, since they are optional. You can use this task to deal with these.

After selecting this task, the Selection by software components screen appears. In the standard setting, all software components are selected. You are able to restrict the amount of objects to be generated by deselecting software components. Use the pushbutton to deselect the software components you want to ignore.

If you interrupt the generation of Web Dynpros before it has finished, or if the system terminates generation, the Regenerate the objects of the last run task allows you to resume the generation.

2. Select Servers for Parallel Generation

After the task selection you have to select the server types for which you want to generate the loads. The generation is based on a parallelized method, where the generation set is divided into small subsets that are processed by parallel processes. Depending on resources, available servers are included in the parallel processing, whereby multiple parallel processes run on one server.

From the Selection of Server for Parallel Generation screen, you can select the servers to be used in the parallel processing. Note that loads depend on the machine type (MT) of a host. The default selection orientates itself by the server to which it is logged on. It corresponds to your logon server and all servers on your system that have the same machine type. If you want to use the default selection, choose Continue.

If you want to exclude individual servers from the generation, or if you want to generate the load for a particular machine type that is different to that of the logon server, then use the push-button to select the corresponding servers. You can also select and deselect all servers of one machine type by choosing Select all <Platform>

Note: The parallel servers are depicted via the logon groups in transaction RZ12. For transaction SGEN, logon group ‘parallel_generators‘ is created. Do not use this group for your own purposes, as transaction SGEN uses and continually redefines this group.

After the server selection the system starts to automatically define the generation set, and to store it on the database (DB table GENSETC). This may take several minutes.

Job Monitor Pushbutton

This function allows you to call the job process control directly without having to redefine the generation set. By choosing Job Monitor -> Job Overview -> Spool or Job Log , you can display logs from previous generation jobs.