Solution : https://service.sap.com/sap/support/notes/65946 (SAP Service marketplace login required)
Summary :
The SAP Note addresses a condition where record locks in the MaxDB database escalate to table locks due to a high percentage of lock list utilization, affecting concurrency by forcing other users to wait. The cause is rooted in the MAXLOCKS parameter governing the lock entry list's maximum size. If user record locks exceed 20% of this list for a table, lock escalation to a table lock is triggered. This can also happen if line locks exceed 5% during a transaction. Adjusting MAXLOCKS and ROW_LOCKS_PER_TRANSACTION thresholds can mitigate this issue. Performance monitoring is advised using transaction ST04, which provides lock-related metrics like Average and Maximum Entries and Escalation counts.
Key words :
st04 -> detail analysis menu -> exclusive lockwaits -> complete lock listthe relevant sql commands, maxdb parameter maxlocks specifies, lock entry list, key figures determined, transaction st04, affect concurrent users, exact memory consumption, symptom record locks, table lock, concurrent users
Related Notes :
| 1308217 | SAP MaxDB Version 7.8: Parameter recommendations |
| 1243937 | |
| 1004886 | MaxDB Version 7.7 parameter recommendations |
| 814704 | MaxDB Version 7.6 parameter settings for OLTP/BW |
| 767635 | MaxDB Version 7.5 parameter settings for OLTP/BW |
| 338631 | Parameter for lock management |
| 68896 | R3trans: Performance problems and cluster |