EBS Reports errors as concurrent jobs

In R12, below command can check if Report Manager is running or not on CM node:

$ ps -ef | grep rwrun

But, it there is no report in Running status in concurrent manager, that command will return nothing.

Troubleshooting on Reports:
 
1. Reports finish, but give error at the end: "REP-57054: In-process job terminated:Finished successfully but output is voided". The behavior matches "Intermittent Oracle Reports REP-0069: REP-57054: Error (Doc ID 1237834.1)".

Workaround:
(1) create a file -  $FND_TOP/admin/template/custom/rwbuilder_conf_1012.tmp
 use the idea in Doc ID 1237834.1 to prevent Autoconfig from clobbering the changes.
(2) modify the file changing one line to <property name="cacheSize" value="50"/>
(3) run autoconfig
(4) verify $INST_TOP/ora/10.1.2/reports/conf/rwbuilder.conf have 50 as the cacheSize.
(5) schedule cron jobs to delete log files.
05 23 * * * /usr/bin/find $INST_TOP/logs/ora/10.1.2/reports/cache/*.txt -mtime +3 -exec rm -rf {} \;
05 05 * * * /usr/bin/find $INST_TOP/logs/ora/10.1.2/reports/cache/*.xml -mtime +7 -exec rm -rf {} \;
05 10 * * * /usr/bin/find $INST_TOP/logs/ora/10.1.2/reports/cache/*.txt -mtime +7 -exec rm -rf {} \;
(replace $INST_TOP with the real path)

2. After submit a CM job/report, the job stays there forever.

It looks like it has difficulties to hit the database. But the real fix is to delete file  $ORACLE_HOME/reports/conf/rwnetwork.conf. 
See "Concurrent Processing - R12 Concurrent Requests Run Forever, rwrun Errors with REP-50125 (Doc ID 737445.1)".

3.