IBM Tivoli Monitoring > Version 6.3 Fix Pack 2 > Installation Guides > Installation Guide > Performance tuning > Tivoli Data Warehouse > Relational database design and performance tuning for DB2 Database servers > Tuning > Database manager configuration tuning
IBM Tivoli Monitoring, Version 6.3 Fix Pack 2
Parameters
The database manager configuration parameters in this section have a high impact on performance.
See the DB2 Administration Guide: Performance for detailed explanations about all the database manager configuration parameters.
- AGENTPRI
- Controls the priority that the operating system scheduler gives to all agents and to other database manager instance processes and threads. Use the default value unless you run a benchmark to determine the optimal value.
- ASLHEAPSZ
- Represents a communication buffer between the local application and its associated agent. The application support layer heap buffer is allocated as shared memory by each database manager agent that is started. If the request to the database manager or its associated reply do not fit into the buffer, they are split into two or more send-and-receive pairs. The size of this buffer should be set to handle the majority of requests using a single send-and-receive pair.
- INTRA_PARALLEL
- Specifies whether the database manager can use intra-partition parallelism on an SMP machine. Multiple processors can be used to scan and sort data for index creation. Usually, this parameter is set to YES, especially if you are running on a dedicated database server. The default value is NO.
- MAX_QUERYDEGREE
- Specifies the maximum degree of intra-partition parallelism that is used for any SQL statement that is executing on this instance of the database manager. An SQL statement does not use more than this number of parallel operations within a partition when the statement is executed. The intra_parallel configuration parameter must be set to a value greater than 1 to enable the database partition to use intra-partition parallelism. Setting the value to ANY enables use of all partitions. Usually, this parameter should be set to ANY, especially if you are running on a dedicated database server. The default value is ANY.
- SHEAPTHRES
- Determines the maximum amount of memory available for all the operations that use the sort heap, including sorts, hash joins, dynamic bitmaps that are used for index ANDing and Star Joins, and operations where the table is in memory. Set the sort heap threshold parameter to a reasonable multiple of the largest SORTHEAP parameter in your database manager instance. This parameter should be at least twice as large as the largest sort heap defined for any database within the instance, but you must also consider the number of concurrent sort processes that can run against your database.
Parent topic:
Database manager configuration tuning