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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.
Management of the virtual portion of shared memoryThe database server uses memory pools to track memory allocations that are similar in type and size.
Size of the virtual portion of shared memoryUse configuration parameters to specify the initial size of the virtual portion of shared memory, the size of segments to be added later, and the amount of memory available for PDQ queries.

Size of the virtual portion of shared memory

Use configuration parameters to specify the initial size of the virtual portion of shared memory, the size of segments to be added later, and the amount of memory available for PDQ queries.

To specify the initial size of the virtual shared-memory portion, set the SHMVIRTSIZE configuration parameter. To specify the size of segments that are added later to the virtual shared memory, set the SHMADD and the EXTSHMADD configuration parameter.

To specify the amount of memory available for PDQ queries, set the DS_TOTAL_MEMORY parameter.

If you want to increase the amount of memory that is available for a query that is not a PDQ query and the PDQ priority is set to 0 (zero), you can change the amount in any of the following ways:

Set the DS_NONPDQ_QUERY_MEM configuration parameter
Run the onmode -wm or the onmode -wf command

For example, if you use the onmode utility, specify a value as shown in the following example:

onmode -wf DS_NONPDQ_QUERY_MEM=500

The minimum value for DS_NONPDQ_QUERY_MEM is 128 KB. The maximum supported value is 25 percent of the value of DS_TOTAL_MEMORY.

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