Re: undo segments online causing performance problems.

When the "hang" occurs, run the following query:

SELECT DECODE(request,0,'Holder: ','Waiter: ')||sid sess,
id1, id2, lmode, request, type
FROM V$LOCK
WHERE (id1, id2, type) IN
(SELECT id1, id2, type FROM V$LOCK WHERE request>0)
ORDER BY id1, request
/

It very well could be that the application is pausing on ENQUEUE waits.

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