Self-tuning memory simplifies the task of memory configuration
by automatically setting values for memory configuration parameters
and sizing buffer pools. When enabled, the memory tuner dynamically
distributes available memory resources among the following memory
consumers: buffer pools, locking memory, package cache, and sort memory.
Self-tuning memory is enabled through the self_tuning_mem database
configuration parameter.
The following memory-related database configuration parameters
can be automatically tuned:
- database_memory - Database shared memory
size
- locklist - Maximum storage for lock list
- maxlocks - Maximum percent of lock list before
escalation
- pckcachesz - Package cache size
- sheapthres_shr - Sort heap threshold for
shared sorts
- sortheap - Sort heap size
Starting withDB2® Cancun
Release 10.5.0.4,
each member in a DB2 pureScale® environment
has its own self-tuning memory manager (STMM) tuner.
Starting with
DB2 Version
10.5 Fix Pack 5,
the following memory-related database configuration parameters can
also be automatically tuned in a
DB2 pureScale environment:
- cf_db_mem_sz - CF Database memory
- cf_gbp_sz - Group buffer pool
- cf_lock_sz- CF Lock manager
- cf_sca_sz - Shared communication area