I’m not really sure about its functionality but like you said, the additional feature was actually there since 2011 so I’m a bit unconvinced that this is the real culprit why this is suddenly slow now. I’m actually in a direction that this standard function K_COSTS_PLAN_INTERFACE_TOTAL works slower in a HANA database and there could be some OSS notes to improve it. Can you still try to test and check if this is the same behavior in QS1? Thanks!