Procedure documentationClass Containers Locate this document in the navigation structure

 

The SAP liveCache data is organized into 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. Each OMS object has a unique object ID (OID) which an application, for example, can use to request the object.

From the Performance user menu of the DBA Cockpit you can, among other things, choose to display information about class containers since the last start of liveCache Monitoring.

You will find more detailed information on the OMS objects in the OMS Object Browser.

Procedure

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 OMS objects for exactly one persistent class. The system displays information from the OMS intermediate layer and the liveCache basis layer.

OMS Intermediate Layer

The OMS (Object Management System) intermediate layer manages the data (that is, the OMS 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, Schema, Class Name, Container Number

SAP liveCache Basis Layer

The OMS 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; the application can only access the data 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, Container Usage, Number of Objects, Wastage, Key Inversions, File ID

You will find more detailed information on the OMS objects in the OMS Object Browser.

Calculation Formulas
  • Number of objects: <Container Size>*8100*(<Ø Container Usage>/100)/(<Object Size>+24)

  • Net size of the liveCache (in KB): SELECT SUM (<Container Size>*<Ø Container Usage>/100)*8

More Information

Class Container Sizes