performance Problems with API in TSO, suspected since ZOS 2.2

Document ID : KB000122809
Last Modified Date : 10/12/2018
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Question:
We migrated to ZOS 2.2 it seems that from that point in time, we have performance problems using the ENDEVOR API in a TSO Session the problem happens in Endevor V16 as well as in ENDEVOR V18 (increment 6). This seems to happen with API LIST requests. Traces show a large number of VSAM I/O activity. Why is performace so poor after upgrading Z/OS ?  
Answer:
Known Problem (P7412). Test apar (TR93444) verified by client.