Disabling self-tuning memory
Self-tuning memory can be disabled for the entire database or for one or more configuration parameters or buffer pools.
About this task
If self-tuning memory is disabled for the entire database, the memory configuration parameters and buffer pools that are set to AUTOMATIC remain enabled for automatic tuning; however, the memory areas remain at their current size.
Procedure
- Disable self-tuning memory for the database by setting the self_tuning_mem database configuration parameter to OFF using the UPDATE DATABASE CONFIGURATION command or the db2CfgSet API.
- To disable the self tuning of memory areas that are controlled by memory configuration parameters, set the relevant configuration parameters to MANUAL or specify numeric parameter values using the UPDATE DATABASE CONFIGURATION command or the db2CfgSet API.
- To disable the self tuning of a buffer pool, set the buffer pool size to a specific value using the ALTER BUFFERPOOL statement.
Results
Note:
- In some cases, a memory configuration parameter can be enabled for self tuning only if another related memory configuration parameter is also enabled. This means that, for example, disabling self-tuning memory for the locklist or the sortheap database configuration parameter disables self-tuning memory for the maxlocks or the sheapthres_shr database configuration parameter, respectively.