Database Management

Reflexive Mergeout

In past releases, the Tuple Mover typically performed mergeout to consolidate ROS containers on two occasions:

• At regular intervals as set by configuration parameter MergeOutInterval
• On user invocations of Vertica meta-function DO_TM_TASK('merge', scope)

This release introduces a reflexive approach to mergeout: the Tuple Mover continuously monitors DML activities such as COPY and table partitioning. Instead of waiting until the MergeOutInterval-specified time span elapses, it executes mergeout as needed, giving special attention to projections that are subject to frequent DML activity. This approach can help avoid performance degradation and ROS pushback.

For details, see Mergeout in the Administrator's Guide.