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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.
Virtual portion of shared memoryThe virtual portion of shared memory is expandable by the database server and can be paged out to disk by the operating system.
Components of the virtual portion of shared memoryThe virtual portion of shared memory stores a variety of data.
Shared-memory internal tablesThe database server shared memory contains seven internal tables that track shared-memory resources.
Chunk tableThe chunk table tracks all chunks in the database server.

Chunk table

The chunk table tracks all chunks in the database server.

If mirroring has been enabled, a corresponding mirror chunk table is also created when shared memory is set up. The mirror chunk table tracks all mirror chunks.

The chunk table in shared memory contains information that enables the database server to locate chunks on disk. This information includes the number of the initial chunk and the number of the next chunk in the dbspace. Flags also describe chunk status: mirror or primary; offline, online, or recovery mode; and whether this chunk is part of a blobspace. For information about monitoring chunks, see Monitor chunks.

The maximum number of entries in the chunk table might be limited by the maximum number of file descriptors that your operating system allows per process. You can usually specify the number of file descriptors per process with an operating-system kernel-configuration parameter. For details, consult your operating-system manuals.