REP-0004,REP-0069 and REP-57054 errors while APXAPRVL program running

I would like to give brief information about REP-57054 , REP-0069, REP-0004 error which occur while invoice validation  -  APXAPRVL concurrent program working .

Error:
REP-0004: Warning: Unable to open user preference file.
REP-0069: Internal error
REP-57054: In-process job terminated:Terminated with error:


Cause of  reports.log file under $APPLCSF/$APPLLOG reached 2GB size limit is the reason of this error.

For solution,

1.Stop concurrent managers
2.Truncate "reports.log" file
3.Restart concurrent managers
4.Observe the results after submitting related concurrent program

I have taken this solution from metalink . But i did not stop managers . Directly truncate reports.log by ">" command has solved my problem.