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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.
Configure and monitor memory cachesThe database server uses caches to store information in memory instead of performing a disk read or another operation to obtain the information. These memory caches improve performance for multiple queries that access the same tables. You can set some configuration parameters to increase the effectiveness of each cache. You can view information about memory caches by running onstat commands.
Monitor and tune the SQL statement cacheThe SQL statement cache stores optimized SQL statements so that multiple users who run the same SQL statement can achieve some performance improvements.
Multiple SQL statement cache poolsUnder some circumstances when the SQL statement cache is enabled, the database server allocates memory from one pool for query structures.

Multiple SQL statement cache pools

Under some circumstances when the SQL statement cache is enabled, the database server allocates memory from one pool for query structures.

These circumstances are:

When the database server does not find a matching entry in the cache
When the database server finds a matching key-only entry in the cache and the hit count reaches the value of the STMT_CACHE_HITS configuration parameter

This one pool can become a bottleneck as the number of users increases. The STMT_CACHE_NUMPOOL configuration parameter allows you to configure multiple sscpools.

You can monitor the pools in the SQL statement cache to determine the following situations:

The number of SQL statement cache pools is sufficient for your workload.
The size or limit of the SQL statement cache is not causing excessive memory management.

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