Procedure documentationMonitoring OMS Versions Locate this document in the navigation structure

 

Pay attention to the following aspects when you monitor OMS versions:

  • Age of an OMS Version

    OMS versions can be processed for several hours and therefore use up increasingly more main memory in the OMS heap. If OMS versions are open for a very long time, the SAP liveCache database has to hold a lot of history data (links to Undo Log entries) which increasingly fills up the data cache. In some circumstances, data is even written from the data cache to the data area. The increase in I/O has a negative effect on SAP liveCache performance. Therefore, do not keep OMS versions open for longer than eight hours.

  • Load on the OMS Heap

    If OMS versions are swapped from the OMS heap, then this data is no longer accessed from the OMS heap but from the data cache. This type of access is significantly bad for performance and should be avoided if possible.

Procedure

Use the OMS Versions display (DBA Cockpit/liveCache Assistant). You can check the ratio of history data to OMS data in the data cache in the Caches display (DBA Cockpit/liveCache Assistant). Use the Monitor display in the liveCache Alert Monitor.

Critical Situations

  • An OMS version is older than eight hours.

    The application must close this OMS version.

    • Schedule the report /SAPAPO/OM_REORG_DAILY once a day in the application system. All OMS versions older than eight hours are deleted.

    • Schedule the report /SAPAPO/OM_DELETE_OLD_SIMSESS every 30 minutes.

  • Some pages of the OMS versions are displaced from the OMS heap (displaced pages).

    • The application must work with less data within an OMS version.

    • You can reduce the size of the data cache (general database parameter CacheMemorySize) and increase the OMS heap (general database parameter OmsMaxHeapSize) instead.

    • You can make more main memory available to increase the size of the OMS heap (general database parameter OmsMaxHeapSize).

  • The amount of history data (link to Undo Log Entries) has risen significantly compared to the OMS data.

    Check whether old OMS versions exist. Check whether the reports /SAPAPO/OM_REORG_DAILY and /SAPAPO/OM_DELETE_OLD_SIMSESS have run.

More Information

Performance Analysis in CCMS: SAP liveCache Technology

Glossary, OMS, OMS Version, OMS Heap

Database Administration, General Database Parameters