The Workflow Manager places a partition point at a multiple input group Custom transformation that requires a single thread for each partition.
For example, consider the following mapping:
Partition Point
Multiple input groups.
Requires one thread for each partition.
Does not require one thread for each partition.
CT_Order_class and CT_Order_Prep have multiple input groups, but only CT_Order_Prep requires one thread for each partition. The Workflow Manager creates a partition point at CT_Order_Prep.