Monday Oct 08, 2012

OOW 2012:
Kings of Leon & Pearl Jam - Appreciation Event

June 15, 1992 - that was actually the day when Pearl Jam played their first concert in Serenadenhof in my hometown, N├╝rnberg. Oups ... that's over 20 years ago ... ;-)

So I was so happy to get a ticket to this year's OOW 2012 appreciation event on Treasure Island. Every year it amazes me over and over again how the organizers manage it logistically to bring almost 40,000 people to and back from the island. Food was ... I would say fairly ok ... and beer (as always) is not - actually even though I'm not a beer drinker I wouldn't call it beer

Kings of Leon did start. I like them a lot and owe their 2008 album Only By Night. That was a good start to warm up the crowd.

And then Pearl Jam took over - and ... wooooooow ... they are such a great live band. First of all as far as I understood they were donating the money they've got for that gig to an NGO. And Eddie Vedder's voice is simply striking ... I had shivers running down my spine. They played a good excerpt of their +20 years career closing down with Alive at the very end. It seemed to everybody that the band had real fun playing there - and it was sooooo good. Thanks a lot to the person who did organize me a ticket :-)

Catching my bus back to my hotel area down at Fisherman's Wharf worked well - but I must have fallen asleep 5 minutes after we've left the parking lot. The next thing I did recognize was the bus driver pushing the breaks at Northpoint. What a wonderful night ...

Wednesday Aug 10, 2011

Upgrade - and an interesting surprise

Patchset 11.2.0.2 is out there for a long, looong time. But still Roy and me - and unfortunately our customers - sometimes experience some nice surprises after upgrade.

Roy did work on the weekend with a financial institution customer in the US to support them during their go-live on Oracle 11.2.0.2 with several systems. It was well tested and long planned. And overall the whole process went well except for one database (see Roy's entry below on the change with JOB_QUEUE_PROCESSES in 11.2.0.2).

Yesterday I've received a text message from Roy to have a closer look into a service request the customer did open due to massive performance problems after go-live. The customer has seen MUTEX S CONTENTION in the AWR and ADDM reports slowing down the whole cluster. And the support people from BDE did a good job to drill down and diagnose the issue. But the solution is an interesting surprise.

The April 2011 PSU 11.2.0.2.2 (Patch 11724916) did contain a fix:
Bug:10187168 Enhancement to obsolete parent cursors if VERSION_COUNT exceeds a threshold

And you might believe that having the fix included in the PSU does enable the code of this fix?? At least I would believe that. But as Roy would call it "the old 'hidden bug fix' trick..." the code is there but you'll have to enable it. MOS Note 10187168.8 describes what you'll have to do.

Actually you'll have to set this hidden parameter:
_cursor_features_enabled=1026
and besides that this nice event in your init.ora/spfile:
events= "106001 trace name context forever, level 1024"
Then bounce the instance ... an voila ... the patch is now enabled.

Scary, isn't it ...
As I've spent 6 years in Oracle's RDBMS Support as well I was first checking the patch readme to see whether this is mentioned somewhere - but the only remark pointing to this bug is:
Bug 10264680 - INCORRECT VERSION_NUMBER REPORTED AFTER PATCH FOR 10187168 APPLIED

Anyway, what is this parameter for?

It's an enhancement request to allow parent cursor to be obsoleted if the version count exceeds a defined threshold. This threshold gets set with the new underscore _cursor_obsolete_threshold.
But due to the fact that other patches included in this PSU don't know about this newly introduced underscore event 106001 has to be set instead. The value equals the threshold.

To make things more complicated and enable this fix now (see my comments above) the underscore _cursor_features_enabled has to be set as well. And its value is dependend on the patch level - for Oracle 11.2.0.2 it is 1026 whereas for Oracle 11.1.0.7 it would be 18.

And let me mention that these parameters will have to be set and adjusted just under Oracle's Support guidance!

About

Mike Dietrich - Oracle Mike Dietrich
Senior Principal Technologist - Database Upgrade Development Group - Oracle Corporation

Based near Munich/Germany and spending plenty of time in airplanes to run either upgrade workshops or work onsite with reference customers. Acting as interlink between customers and the Upgrade Development.

Contact me either via XING or LinkedIn

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