Analyzing and Solving Problems

Procedure

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<sapsystemname>.
Problems with the Enqueue Server. If you are not operating AS ABAP with the standalone enqueue server, check the following settings:
- An application server is running with enqueue functions (see transaction SM51), whose name is identical to the parameter rdisp/enqname (also identical use of upper/lower case).
  You can see the current value of the parameter in the parameter maintenance (transaction RZ11).
- Parameter rdisp/myname is set correctly
- Number of enqueue work processes (rdisp/wp_no_enq is at least 1
If you are using the Standalone Enqueue Server (as part of an (A)SCS instance), check the parameter settings: Profile Parameter Settings for the Standalone Enqueue Server.
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.
For more information, see:

Testing for Locking Problems

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 Text
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
1047180	Problem analysis in the standalone enqueue server
696611	Check J2EE lock handler

Notes About Configuration, Resources, and Performance

Note Number	Short Text
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 Text
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	FM: 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