Runtime Errors TIME_OUT

Question

guyz,
i am facing the below issue while running DTP to load the master data attr to info object.
previoulsy it was working perfect but from last few days its getting hanged and throwing this error.
also records are very few around 2500.
dont know why its getting hanged.
Runtime Errors         TIME_OUT
Date and Time          10/04/2011 16:35:09
Short text
     Time limit exceeded.
What happened?
     The program "SAPLSENA" has exceeded the maximum permitted runtime without
     interruption and has therefore been terminated.
What can you do?
     Note down which actions and inputs caused the error.
     To process the problem further, contact you SAP system
     administrator.
     Using Transaction ST22 for ABAP Dump Analysis, you can look
     at and manage termination messages, and you can also
     keep them for a long time.
Error analysis
     After a specific time, the program is terminated to make the work area
     available to other users who may be waiting.
     This is to prevent a work area being blocked unnecessarily long by, for
     example:
     - Endless loops (DO, WHILE, ...),
     - Database accesses with a large result set
     - Database accesses without a suitable index (full table scan)
     The maximum runtime of a program is limited by the system profile
     parameter "rdisp/max_wprun_time". The current setting is 600 seconds. If this
      time limit is
     exceeded, the system attempts to cancel any running SQL statement or
     signals the ABAP processor to stop the running program. Then the system
     waits another 60 seconds maximum. If the program is then still active,
     the work process is restarted.
How to correct the error
    Programs with long runtime should generally be started as background
    jobs. If this is not possible, you can increase the system profile
    parameter "rdisp/max_wprun_time".
    Depending on the cause of the error, you may have to take one of the
    following measures:
    - Endless loop: Correct program;
    - Dataset resulting from database access is too large:
      Instead of "SELECT * ... ENDSELECT", use "SELECT * INTO internal table
      (for example);
    - Database has unsuitable index: Check index generation.
    If the error occures in a non-modified SAP program, you may be able to
    find an interim solution in an SAP Note.
    If you have access to SAP Notes, carry out a search with the following
    keywords:
    "TIME_OUT" " "
    "SAPLSENA" or "LSENAF01"
    "FLUSH_PACKAGE"
    If you cannot solve the problem yourself and want to send an error
    notification to SAP, include the following information:
    1. The description of the current problem (short dump)
       To save the description, choose "System->List->Save->Local File
    (Unconverted)".
    2. Corresponding system log
       Display the system log by calling transaction SM21.
       Restrict the time interval to 10 minutes before and five minutes
    after the short dump. Then choose "System->List->Save->Local File
    (Unconverted)".
    3. If the problem occurs in a problem of your own or a modified SAP
    program: The source code of the program
       In the editor, choose "Utilities->More
    Utilities->Upload/Download->Download".
    4. Details about the conditions under which the error occurred or which
    actions and input led to the error.
also sometimes when i try to refresh the requests in the manage option of the info object, it doesnt show the previous requests and throws the message
Refresh of the display terminated because InfoCube/DSO cannot be locked
Message no. RSM854
Diagnosis
InfoProvider 0PROD_CATEG cannot be locked with lock argument RSICCONT.
System Response
The display is not refreshed and contains old or incorrect data, that can come from other InfoProviders.
Procedure
Check why the sm12 lock is not yet released on the table RSICCONT; Where necessary delete the lock.
With reproduction of an unauthorized lock, write a message to SAP.
please guide.
cheerz,
raps.

Answer 1

Dear Raps,
The program SAPLSENA is the lock handler tool. It is doing
enqueue/dequeue operations.
The error should come from the program created running in this dialog
process and calls the SAPLSENA program to create the lock.
The problem actually occurs because an application program commits many
separate calls of DEQUEUE function modules, and thus causes the
dispatcher queue in the enqueue dispatcher to overflow. Such an
application program always causes a performance problem. DEQUEUE calls
are started asynchronously, that is, they normally do not give a
response, and the calling program continues without waiting time.
If an overflow of the ENQ dispatcher queue occurs in this case, locks
are kept forever, and processes that are waiting for an enqueue
response, will keep hanging.
Please kindly refer to some notes for more information.
653996     Analyzing lock situations
142054     Processes in status stopped ENQ
97760      Enqueue: Performance and resource consuption
74141      Resource Management for tRFC and aRFC
39412      How many work processes to configure
Please check as well attached note 74141 for RFC load distribution.
Regards,
arvind