Improved INSERT performance for unclustered data

Db2 12 introduces insert algorithm 2 (IAG2), which can improve the performance of INSERT operations for unclustered data.

Using IAG2 can result in an increase in insert throughput, especially with data that is not indexed. IAG2 can also reduce logging and reduce class 2 elapsed time and class 2 CPU time.

IAG2 applies only to universal table spaces (UTS) with the MEMBER CLUSTER attribute. IAG2 does not apply to other table space types.

You can control the insert algorithm used for individual table spaces by specifying the INSERT ALGORITHM option in CREATE TABLESPACE or ALTER TABLESPACE statements. To specify the system-wide setting for default insert algorithm, use the DEFAULT_INSERT_ALGORITHM subsystem parameter.

Recommendation: To determine the group buffer pool size when insert algorithm 2 is used for concurrent INSERT operations from multiple data sharing members, allocate a minimum of 2000 * n directory and data entries (where n is the number of members).