Parallel processing and time-out

Question

Hi all,
I've got a prob with doing a great number of postings.
While the time elapsed for these postings is too long, I tried to do it with an function module and "IN BACKGROUND TASK". Well, there is also a alternative "STARTING NEW TASK".
But I figured out, that these both variants are starting dialog work processes. I think there is a time out for dialog WP's of 300 seconds in standard.
Will this timeout kill the processes or not??
And witch alternative is the best to do some parallel processing??
thanx in advanced
regards
Olli

Answer 1

Hi Oliver,
Some solutions here:
1. You could increase the value of the dialog time-out (allthough this can only go to a maximum of 600 seconds). This parameter is in the SAP profiles (parameter name = rdisp/max_wprun_time).
2. As suggested by Christian, decrease the amount of work within one LUW. You can do this by inserting (from time to time) a COMMIT WORK. This COMMIT WORK also resets the timeslice counter of the running dialog process (thus giving again an extra timeslice to work). The downside is, that if you have many related objects to modify, your ROLLBACK options become limited.
3. Split the proces in several tasks and put the to work in the background (by scheduling jobs for them).
4. Program your own parallel handler (see sample code). With this you could process document by document (as if each is done separately). The number of dialog processes (minus 2) is the limit you could use.
Sample code:
* Declarations
CONSTANTS:
  opcode_arfc_noreq TYPE x VALUE 10.
DATA:
   server       TYPE msname,
   reason       TYPE i,
   trace        TYPE i VALUE 0,
   dia_max      TYPE i,
   dia_free     TYPE i,
   taskid       TYPE i VALUE 0,
   taskname(20) TYPE c,
   servergroup  TYPE rzlli_apcl.
* Parallel processes free check
CALL 'ThSysInfo' ID 'OPCODE' FIELD opcode_arfc_noreq
                 ID 'SERVER' FIELD server
                 ID 'NOREQ'  FIELD dia_free
                 ID 'MAXREQ' FIELD dia_max
                 ID 'REASON' FIELD reason
                 ID 'TRACE'  FIELD trace.
IF dia_free GT 1.
  SUBTRACT 2 FROM dia_free.
  SUBTRACT 2 FROM dia_max.
ENDIF.
* You must leave some dialogs free (otherwise no one can logon)
IF dia_free LE 1.
  MESSAGE e000(38)
     WITH 'Not enough processes free'.
ENDIF.
* Prepare your run
ADD 1 TO taskid.
WRITE taskid DECIMALS 0 TO taskname LEFT-JUSTIFIED.
CONDENSE taskname.
* Run your pay load
CALL FUNCTION 'ZZ_YOUR_FUNCTION'
  STARTING NEW TASK taskname
  DESTINATION IN GROUP servergroup
  EXPORTING
*   Your exporting parameters come here
  EXCEPTIONS
    communication_failure  = 1
    system_failure         = 2
    RESOURCE_FAILURE       = 3
    OTHERS                 = 4.
Of course you would put this within a loop and let your "payload" function fire off for each document.
You MUST check the number of free processes just before you run the payload.
And as last reminder: Do NOT use the ABAP statement WAIT (this will disrupt the counting of free processes).
Hope this will help you,
Regards,
Rob.