OMS heap
The OMS heap is only used by SAP liveCache database instances.
In addition to the data cache and the converter, SAP liveCache database instances also use a private OMS cache in the working memory during operation: the OMS heap. The OMS heap contains local copies of the OMS data and local application data.
See also:
Concepts of the Database System,
Database Administration in CCMS: SAP liveCache Technology
Heap Usage
Monitoring the Main Memory Areas