Bookshelf v7.8: About Managing the Dynamic Statement Cache

Because DB2 uses the Environmental Descriptor Manager (EDM) component to manage the dynamic statement cache, it is important that you set EDM-related system parameters to appropriate values. Prior to DB2 for z/OS v8, the cached SQL statements were stored in either the primary EDM Pool, or in a data space. In DB2 for z/OS v8, the cached SQL statements are always stored in a dedicated area above the 2GB bar. For guidance on setting the EDM system parameters, see your IBM documentation.

NOTE: Monitor and adjust the EDM Pool and the related cache storage areas based on your workload.

System parameters associated with dynamic statement caching are described in Table 16.

Table 16. System Parameters Associated with Dynamic Statement Caching
Parameter	Value	Description
CACHEDYN	YES	Enables dynamic statement caching.
`CONTSTOR`	`YES`	Contracts working storage for connections periodically (every 50 commits or when storage use reaches 2 MB).
`EDMDSPAC`	`10000`	Overrides size of data space for EDM pool during statement caching in DB2 for z/OS v7.
`EDMPOOL`	`32768`	EDM pool storage size in KB.
EDMSTMTC	102400	Global statement cache size, in KB, used by EDM in DB2 for z/OS v8.
`MINSTOR`	`YES`	Minimizes thread storage usage.