Identify blocking session for cursor: pin S wait on X when database is hung

 Platform : Solaris(64-bit)
RDBMS Version: 11.1.0.7.2

Our production database experienced hang and we could not connect to sqlplus and hang cleared on its own after few minutes. From AWR report for duration of the hang Top 5 Timed Foreground Events were:

  Event Waits Time(s) Avg wait (ms) % DB time Wait Class cursor: pin S wait on X
34,422,745 688,152 20 49.78 Concurrency row cache lock 205,545 518,821 2524 37.53 Concurrency library cache load lock 778 110,728 142324 8.01 Concurrency DB CPU 27,809 2.01 rdbms ipc reply 16,003 22,098 1381 1.60 Other

*Found this MOS document : HOW TO FIND BLOCKING SESSION FOR MUTEX WAIT EVENT
cursor: pin S wait on X [ID 786507.1] *however when the issue occured could not get connection to sqlplus
**
*QUESTION:* Is there a way to find out blocker session for this wait event
after the fact the issue got cleared and the sessions got completed?

Other research done and metalink notes found were:

Found this note: *"Cursor: Pin S Wait On X" Contention Mutex Sleep Reason Primarily ' kkslce [KKSCHLPIN2]' [ID 1268724.1]*

  Mutex Type Location Sleeps Wait Time (ms) Cursor Pin kkslce [KKSCHLPIN2] 31,465,924 -3,361,856 Cursor Pin kksfbc [KKSCHLFSP2] 3,607,296 2,750,834 Cursor Parent kksfbc [KKSPRTLOC1] 406,049 1,120
**

Although we have above event the solution mentioned in this note is not relevant in our environment.
**

I have found this bug: Bug 7234778 Unnecessary "cursor: pin S wait on X" wait and I am going to follow up with oracle support on this with service request.

Regards,
Sanjeev.

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