alter java class "oracle/apps/per/proxy/client/forms/UrlThread" compile hangs

Mohan pinged me today and said:

Two workers are hung and log file says 

Loading contents of archive file into database with arguments

-Xmx512M -XX:+UseParallelGC -XX:ParallelGCThreads=4 -XX:LargePageSizeInBytes=4M oracle.aurora.server.tools.loadjava.LoadJavaMain -f -thin -user "APPS/*****@someserver.justanexample.com:1521:dba" /$APPLCSF/$APPLOUT/p001ldjva.jar 

I asked him to check v$session_wait, and he reported back:

COUNT(*) EVENT

--------- -----------------------------------

1 Streams AQ: waiting for messages in

the queue

2 row cache lock

4 Streams AQ: qmn slave idle wait

3 library cache lock

1 Streams AQ: qmn coordinator idle wa

it

1 Streams AQ: waiting for time manage

ment or cleanup tasks

SQL_TEXT

----------------------------------------------------------------

alter java class "oracle/apps/per/proxy/client/forms/UrlThread" compile 

I asked him to check the DB alert log.  This is what he found:

WAITED TOO LONG FOR A ROW CACHE ENQUEUE LOCK! 

There are a lot of metalink notes if you search for the above phrase.  All of them indicate latch contention of some sort.

I asked Mohan to stop the patch.  Bounce the database and restart the patch.

After bouncing the database and restarting the patch, the issue went away.