Analyzing and Solving Problems 
Most problems with lock management can be put down to the following causes:
· Problems with communication (network). Check the network.
· Problems with the message server. Check that the message server is running (process msg_server or ms.sap<sap system name>
· Problems with the Enqueue Server. Check the following settings:
¡ An application server is running with enqueue functions (compare SM51), whose name is identical to the parameter rdisp/enqname in profile DEFAULT.PFL (also identical use of upper/lower case).
¡ Parameter rdisp/myname is set correctly.
¡ Number of enqueue work processes (rdisp/wp_no_enq) is at least 1.
· Configuration of the other application servers. Parameters rdisp/enqname and rdisp/mshost must be set up on the enqueue or message server on the other instances.
Lock table is full. Check the system log (SM21) for messages about this topic and execute the enqueue diagnosis functions (see Testing Lock Management).
See also Subsequent Analysis of Lock Table Overflows
SAP notes
The following tables contain the most important SAP notes about the lock concept. They provide help on error analysis, on performance and configuration issues, and on handling specific error cases.
Notes About Error Analysis
Note Number |
Short texts |
125041 |
Analysis of enqueue errors using enqueue logging |
597024 |
Enqueue log, sequence of operations not guaranteed |
658495 |
Improved options with enqueue logging |
746138 |
Analyzing log table overflows |
696611 |
Check j2ee lock handler |
746138 |
Analyzing log table overflows |
Notes About Configuration, Resources, and Performance
Note Number |
Short texts |
97760 |
Enqueue: performance and resource consumption |
564789 |
Too many RFC connections from ENQUEUE_READ to the central instance |
127773 |
Several enqueue work processes |
670238 |
SM12 Confirmation prompt with large number of log entries |
524816 |
Standalone enqueue server |
Notes About Error Situations
Note Number |
Short texts |
734728 |
Syslog GI0 and GI2 (unable to reach central lock handler) |
43614 |
Enqueue, remaining log entries |
79001 |
Error when reading a lock handler file (syslog GEL) |
79084 |
Syslog: Error when writing the lock handler file |
138542 |
Enqueue request fails |
138559 |
Display of enqueue logging file incorrect |
149166 |
Enqueue: GE9, accumulated wait time for lock |
170602 |
Error Message: LOG R1J=> ThAdXEnqState, reset mode <<user name>> |
187787 |
Enqueue queue overflow |
337007 |
GEJ error when opening a lock handler file |
488036 |
Unable to reach central lock handler |
491518 |
FM: Enqueue server in trouble |
625877 |
Locks remain |
654328 |
Enqueue: syslog message GE9 |
712559 |
Core dump in work process in function EnqueQueryRemote |
726473 |
Standalone enqueue server writes to ENQBCK file |