MAIN_RESERVED_DBSPACE_MB Option

Integer greater than or equal to 200, in megabytes

200; SAP IQ actually reserves a maximum of 50% and a minimum of 1% of the last read-write file in IQ_SYSTEM_MAIN

Option can be set at the database (PUBLIC) level only.

Requires the SET ANY SYSTEM OPTION system privilege to set this option. Takes effect immediately.

MAIN_RESERVED_DBSPACE_MB controls the amount of space SAP IQ sets aside in the IQ main store for certain small but critical data structures used during release savepoint, commit, and checkpoint operations. For a production database, set this value between 200MB and 1GB, or at least 20 percent of IQ_SYSTEM_MAIN size. The larger your IQ page size and number of concurrent connections, the more reserved space you need.

Reserved space size is calculated as a maximum of 50 percent and a minimum of 1 percent of the last read-write file in IQ_SYSTEM_MAIN.

SAP IQ ignores the MAIN_RESERVED_DBSPACE_MB option if the actual dbspace size is less than twice the size of the MAIN_RESERVED_DBSPACE_MB value. In dbspaces less than 100MB (such as the demo database), half the usable space may be reserved.