stat_heap_sz - Statistics heap size configuration parameter

This parameter indicates the maximum size of the heap used in collecting statistics using the RUNSTATS command. The constraint set by this parameter applies to each RUNSTATS operation.
With Version 9.5, this database configuration parameter has a default value of AUTOMATIC, meaning that it increases as needed until either the appl_memory limit is reached, or the instance_memory limit is reached.
Configuration type
Parameter type
  • Configurable online
  • Configurable by member in a Db2® pureScale® environment
Default [range]
32-bit platforms
Automatic [1 096 - 524 288]
64-bit platforms
Automatic [1 096 - 2 147 483 647]
Note: The default value is subject to change by the Db2 Configuration Advisor after initial database creation.
Unit of measure
Pages (4 KB)
When allocated
When the RUNSTATS utility is started
When freed
When the RUNSTATS utility is completed

Recommendation: RUNSTATS memory requirements depend on several factors. More memory is required with more statistic options, for example if LIKE statistics or DETAILED index statistics are being collected. When column statistics are collected, gathering statistics of a higher number of columns will require more memory. When distribution statistics are being collected, gathering a higher number of frequent, quantile values, or both will require more memory. The default setting of AUTOMATIC is recommended.