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AdministeringIn addition to administering the database server, you can tune performance, replicate data, and archive data.
System administrationThese topics contain concepts, procedures, and reference information for database and database server administrators to use for managing and tuning HCL OneDB™ database servers.
Administrator's GuideThe HCL OneDB™ Administrator's Guide provides the information required to administer HCL OneDB™.
Disk, memory, and process management
Shared memoryThese topics describe the content of database server shared memory, the factors that determine the sizes of shared-memory areas, and how data moves into and out of shared memory.
Processes that attach to shared memoryA number of processes attach to the database server shared memory.
How virtual processors attach to shared memoryThe database server virtual processors attach to shared memory during setup.
Obtain key values for shared-memory segmentsThe values of the SERVERNUM configuration parameter and shmkey, an internally calculated number, determine the unique key value for each shared-memory segment.

Obtain key values for shared-memory segments

The values of the SERVERNUM configuration parameter and shmkey, an internally calculated number, determine the unique key value for each shared-memory segment.

To see the key values for shared-memory segments, run the onstat -g seg command. For more information, see the sections on SHMADD and the buffer pool in your HCL OneDB™ Performance Guide.

When a virtual processor requests that the operating system attach the first shared-memory segment, it supplies the unique key value to identify the segment. In return, the operating system passes back a shared-memory segment identifier associated with the key value. Using this identifier, the virtual processor requests that the operating system attach the segment of shared memory to the virtual-processor address space.