Reorganizing the TREX System Landscape

Integration

This function is available in the TREX admin tool (standalone) in the area Start of the navigation path Landscape Next navigation step Reorg End of the navigation path and in the TREX admin tool in the SAP system (transaction TREXADMIN).

You can also launch it from the BI Accelerator Monitor. However, several screens are used in this case.

The TREX alert server contains the reorg check. When this check runs, you are automatically informed by e-mail (if configured), if the system recommends a reorganization.

Features

Based on different key figures, TREX calculate whether a reorganization should be performed. The key figures are summarized on the Summary tab page and displayed in detail on the Usage by Service (I) and (II) and Usage by Index tab pages.

The Landscape: Reorg window contains the following tab pages:

Overview of Tab Pages

Tab Page	Description
Summary	Displays whether TREX recommends a reorganization. The lower table displays key figures from which TREX calculates the percentage improvement that could be achieved by a reorganization. These estimates are compared with fixed program-internal values. If the estimated improvement is high enough, TREX recommends the reorganization. If TREX recommends a reorganization (summary = yes), you can start the reorganization immediately or at a later time. To start the reorganization immediately, choose Start Reorg. To start the reorganization later, specify the date and time in the following format: YYYY-MM-DD HH:MM:SS. Then choose Start Reorg.
Plan	Displays the various steps that TREX would perform during a reorganization or that are being performed during a reorganization In addition, you see the steps and the status of the latest reorganization.
Usage by Service (I)	Displays the memory load and CPU load of the hosts in graphical form. Based on these values and irrespective of the selected algorithm, TREX calculates whether a reorganization is necessary. For example, TREX recommends a reorganization if the distribution of memory is unbalanced (identifiable by the different heights of the bar displays). You can use a filter to show and hide the CPU load. You cannot perform any other activities on this tab page, it is mainly for information purposes.
Usage by Service (II)	Displays various key figures for the hosts in table form. You cannot perform any activities on this tab page, it is mainly for information purposes.
Usage by Index	Displays various key figures for all indexes in table form. You can use a filter to define which indexes should be displayed. You cannot perform any other activities on this tab page, it is mainly for information purposes.
Interactive Reorg	Displays various current key figures in table and graphical form. On the graphic view, you can distribute the indexes manually using Drag&Drop. This function is intended for experts.
Options	You can define the algorithm and various parameters to be used for the reorganization. We recommend that you use the memory algorithm. All other algorithms are used for test purposes. Normally, you do not have to make any changes on this tab page.

A reorganization can be necessary in the following circumstances:

You make changes to your TREX system landscape. For example, you remove index servers or add new ones.
The current size of indexes does not match the initial size estimates.

Note

If indexes are moved during the reorganization, no update of the affected indexes is possible. Indexing is interrupted for the duration of the reorganization. The affected indexes are displayed with a yellow traffic light in the Index: Landscape window.

Parameter Overview

The following parameters are available on the Options tab page. You do not have to make any changes by default.

Parameter	Description
`Split Indexes`	Specifies whether indexes are split into logical indexes with more than one part if the defined size is exceeded. This specification is in KB. This parameter is deactivated by default.
`Merge Indexes`	Specifies whether parts of indexes are merged if the size falls below a defined value. This specification is in KB. This parameter is deactivated by default.
`Small Indexes`	Specifies whether small indexes are distributed equally among the available hosts if the size falls below a defined value. This specification is in KB. This parameter is activated by default and has the size 1,000 KB.
`Remove Temporary Indexes`	If it is activated, temporary indexes are deleted during the reorganization. This parameter is activated by default.

Activities

Navigate to the Landscape: Reorg Summary window. If TREX recommends a reorganization (summary = yes), you start the function by choosing Start Reorg. This display switches automatically to the Plan tab page. The window displays which steps are being performed. You can choose the F5 button to update the display.
To cancel the reorganization, choose Cancel Reorg.
The reorganization is complete once all planned steps have been performed. The Summary tab page displays the status done.