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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.
Performance GuideThe HCL OneDB™ Performance Guide describes how to configure and operate your HCL OneDB™ database server to improve overall system throughput and to improve the performance of SQL queries.
Effect of configuration on memory utilizationThe combination of operating-system and HCL OneDB™ configuration parameters can affect memory utilization.
Configuration parameters that affect memory utilizationA large number of configuration parameters in the ONCONFIG file affect memory utilization and performance.
Setting the size of the buffer pool, logical-log buffer, and physical-log bufferThe values that you specify for the BUFFERPOOL, DS_TOTAL_MEMORY, LOGBUFF, and PHYSBUFF configuration parameters depend on the type of applications that you are using (OLTP or DSS) and the page size.
The DS_TOTAL_MEMORY configuration parameter and memory utilizationThe DS_TOTAL_MEMORY configuration parameter places a ceiling on the amount of shared memory that a query can obtain. You can use this parameter to limit the performance impact of large, memory-intensive queries. The higher you set this parameter, the more memory a large query can use, and the less memory is available for processing other queries and transactions.
Deriving a minimum for decision-support memoryIn the first part of the algorithm that the database server uses to derive the new value for the DS_TOTAL_MEMORY configuration parameter, the database server establishes a minimum amount for decision-support memory.

Deriving a minimum for decision-support memory

In the first part of the algorithm that the database server uses to derive the new value for the DS_TOTAL_MEMORY configuration parameter, the database server establishes a minimum amount for decision-support memory.

When you assign a value to the DS_MAX_QUERIES configuration parameter, the database server sets the minimum amount of decision-support memory according to the following formula:

min_ds_total_memory = DS_MAX_QUERIES * 128 kilobytes

When you do not assign a value to the DS_MAX_QUERIES configuration parameter, the database server uses the following formula instead, which is based on the value of information in the VPCLASS configuration parameter:

min_ds_total_memory = NUMBER_CPUVPS * 2 * 128 kilobytes