RE: Enq: SS Contention

From: Upendra nerilla <nupendra_at_hotmail.com>
Date: Tue, 8 Sep 2015 12:47:54 -0400
Message-ID: <BLU181-W36A2092A4EC6CEF7429EE1D8530_at_phx.gbl>



Thanks Karth. I could find the session history.

From the DBA_HIST_ACTIVE_SESS_HISTORY, I could see the blocking_session, serial#, Inst_id. In this case, the session seems to be blocking itself. Any suggestions on how to troubleshoot it further?

Thanks
UpendraSubject: Re: Enq: SS Contention
From: keyantech_at_gmail.com
Date: Sun, 6 Sep 2015 07:18:49 -0400
CC: oracle-l_at_freelists.org
To: nupendra_at_hotmail.com

Upendra
For your first question I guess you were looking for DBA_HIST_ACTIVE_SESS_HISTORY http://docs.oracle.com/cd/B19306_01/server.102/b14237/statviews_3125.htm Karth

Sent from my IPhone
On Sep 6, 2015, at 5:13 AM, Upendra nerilla <nupendra_at_hotmail.com> wrote:

Hello Everyone -

Oracle RAC 11.2.0.3 on OEL 5.x

Recently we had a meltdown of our production environment with "Enq: SS Contention" wait event. I noticed a blocking session responsible for most of the damage. With ASH report I am able to identify the blocking session ID, Serial#, instance etc.

However when I query the v$active_session_history, I don't see corresponding session. Is there a way to find out this information? I am interested in finding out the historical v$session info like client_info, module, program, osuser etc. This issue happened on 9/4, so I still have the ASH data, but not for long.

It would be great if you could suggest any way to find out this..

Second part of the question is, I know the contention is related to Temp tablespace based on the values from p1, p2, p3. What might cause SS enqueue contention? How could I reduce the possibility of having one in future? FYI, I already have 1 tempfile/per each Oracle RAC node.

Thanks in advance
-Upendra
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http://www.freelists.org/webpage/oracle-l Received on Tue Sep 08 2015 - 18:47:54 CEST

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