Version 11.5 contains numerous SQL performance enhancements that continue to make the
Db2 data server
an industrial-strength data server solution that is suitable for any size of organization.
The following table displays a list of performance enhancements in V11.5
Table 1. Performance
enhancements in V11.5
||Support for storage devices that use a 4KB sector size is now supported in production
environments. For details, see the DB2_4K_DEVICE_SUPPORT registry variable.
|SQL insert and update statement
||SQL based insert and update statements for columnar tables are optimized to support large
data sets efficiently, and encoding dictionary creation for such operations are also
|Encoding dictionary support for
SQL insert and update
||Encoding dictionary support for SQL based insert and update statements for columnar tables
are enhanced to provide encoding in some cases where encoding was not previously possible including
for Declared Global Temporary Tables, Not Logged Initially tables, and tables created using Create
Table As Select statements.
|Added support for deferred memory
||Support for deferred memory commit is available as a technical preview, but is not supported
for production environments until further notice. For details, see the DB2_DEFER_MEMORY_COMMIT registry variable. This feature will improve the
performance of large memory allocations, such as those that occur during database activation and
some STMM tuning operations.
|Automatic collection of column group
||The automatic statistics collection in Db2 is updated to discover and collect column group
statistics on base tables. This feature is not enabled by default. It must be enabled with the new
database configuration parameter, AUTO_CG_STATS. When enabled, column group
statistics are automatically collected and maintained.