Procedure documentationClass Containers Locate this document in the navigation structure

 

The SAP liveCache data is organized in classes. Each class can consist of different containers. The OMS objects in a class can be distributed across multiple containers. Each container can consist of multiple page chains.

In the Performance user menu, you can find, among other things, a display of information about class containers since the last start of the liveCache Monitoring.

Prerequisites

The user has been assigned a role in accordance with the authorization concept. You can reach the user menu of the user with the authorizations that correspond to his or her role.

Procedure

  1. In the user menu, choose liveCache Assistant (transaction LC10).

  2. Enter the name of the database connection. You can select the name from the list of existing names. You can restrict the search for the required name.

  3. Choose   liveCache   Monitoring  .

  4. Choose   Problem Analysis   Performance   Class Container  .

or

Open the DBA Cockpit (transaction DBACOCKPIT) and choose   Performance   Class Container  .

You can select the displays as follows:

  • Selection of class containers (restriction by entering class name, schema name and/or container number. You do not need to enter the complete name or number. You can enter ranges, such as S* or similar)

  • All class containers (do not specify restriction)

Result

The system displays information about class containers. Every class container contains objects for exactly one persistent class. The system displays information from the OMS intermediate layer and the SAP liveCache basis layer.

OMS Intermediate Layer

The OMS (Object Management System) intermediate layer manages the data (the objects) that are held in the application-specific OMS heap. The application always accesses its OMS data through the OMS intermediate layer and not directly with the SAP liveCache basis layer. If the data is not in the OMS intermediate layer, it is implicitly loaded from the data cache into the OMS intermediate layer. The system displays, among other things, the following analysis data which provides information about the OMS intermediate layer:

Class ID, Class Name, Schema, Container Number

SAP liveCache Basis Layer

The objects are managed in the SAP liveCache basis layer. The data itself is located in the data cache and in the data area. The application cannot access this data directly; it can access the data only if it is in the OMS intermediate layer. The system displays, among other things, the following analysis data which provides information about the SAP liveCache basis layer:

Object Size, Container Size, Free Container Pages, Empty Container Pages, Key Pages, Average Conatiner Usage, Number of Objects, Wastage, Key Inversions, File ID

Calculation Formulas
  • Number of objects: <Container_Size>*8100*(<Average_Container_Usage>/100)/(<Object_Size>+24)

  • Net size of the liveCache (in KB): SELECT SUM (<Container_Size>*<Average_Container_Usage>/100)*8

More Information

DBA Cockpit, Class Container Sizes

liveCache Assistant, Class Container Sizes