The SAP HANA Troubleshooting and Performance Analysis Guide contains a chapter on "Multiversion Concurrency Control (MVCC) Issues". I have a HANA database (rev. 83) where quite often the number of versions raises over time to values up to 4 million. The SQL statement from the SAP guide gives results like this:
select * from m_mvcc_tables where host='host' and port='30003' and (name='NUM_VERSIONS' or name='MAX_VERSIONS_PER_RECORD' or name='TABLE_ID_OF_MAX_NUM_VERSIONS');
HOST,PORT,NAME,VALUE
"host",30003,"NUM_VERSIONS","91652"
"host",30003,"MAX_VERSIONS_PER_RECORD","539"
"host",30003,"TABLE_ID_OF_MAX_NUM_VERSIONS","3364958" -> table SYS.P_USERS_
In the HANA Studio I see a history of the active versions like this:
The table SYS.P_USRES_ contains 1645 entries. I suspect the users from the SAP BW system (table USR02) are being replicated into the HANA database (table P_USER_). The HANA database is also being used as a BO datasource. The SAP Troubleshooting Guide doesn't provide hints how to fix such an issue. Any tips?
Regards,
Mark