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Secret hacking session – full scans, direct path reads, object level checkpoints, ORA-8103s! (again)

I’m mentioning this again just in case you missed the announcement (because I posted it on the weekend):


There will be anotner free Secret hacking session – about full scans, direct path reads, object level checkpoints, ORA-8103s!

It will happen tomorrow, Tuesday 9th August, online!


Register here:

See you soon!


Training Schedule for 2011 and Public Appearances

Online Seminars
A lot of people have asked me about whether I’d be doing any more seminars in the future. And the answer is yes – at least this year (might be too busy running a company the next year ;-)
I have finally put together the schedule for my 2011 seminars. In addition to the Advanced Oracle Troubleshooting seminar I will also deliver my Advanced Oracle SQL Tuning and Oracle Partitioning and Parallel Execution for Performance seminars, which I have done only onsite in past.
So, check out the seminars page:
Also don’t forget the Expert Oracle Exadata virtual conference next week!
Public Appearances

Oracle OpenWorld 2. October
  • I will talk about Large-Scale Consolidation onto Oracle Exadata: Planning, Execution, and Validation
  • Session ID 09355
Maybe I’ll lurk around the UKOUG venue as well in december ;-)

The First Exadata Virtual Conference in the World!

We have been secretly planning something with Kerry Osborne – and now it’s official – we will host The First Exadata Virtual Conference in the World, on 3-4 August 2011.

This conference takes place a couple of weeks after our Expert Oracle Exadata book is published (on 18. July – check out the awesome new cover design). So, we thought it’d be a good idea to run this conference, where we can explain some things in a different format, do live demos and answer questions that attendees have.

On the first day Kerry and Randy will talk about some serious fundamentals of Exadata, like how Exadata Smart Scan Offloading works and how to make the IO resource manager work for you (especially important in mixed workload consolidated environments).

And on the second day we’ll dig even deeper, with Andy Colvin talking about how to survive Exadata patching (he has patched more Exadatas than anyone else I know) and me following up with some complex performance troubleshooting stories I’ve encountered recently (trust me – there’s a LOT of issues to troubleshoot ;-)

About the Conference:

Since its release, Oracle Exadata quickly became a hit. Due to the relative “youth” of Exadata technology and internal behavior changes introduced with frequent patch-sets, there’s not much up-to-date quality technical information and know-how available to public. This virtual conference brings you a chance to learn from the leading Exadata experts, from their experience of working with real Exadata environments, from Exadata V1 to the latest X2-8. Additionally, there is plenty of Q&A time scheduled, so you can also get answers to your Exadata-related questions.

The speakers are probably some of the most experienced Exadata consultants in the world, in the field of Exadata deployment, migration, performance, and troubleshooting. Also, Kerry, Randy and Tanel are the authors of the #2970a6; text-decoration: none; padding: 0px; margin: 0px;\" href="">Expert Oracle Exadata book published by Apress in July 2011.


  • 3-4 August 2011


  • Online (or should I say “the Cloud” ;-)


  • 8am – 12pm (PST) on both days – 2 x 1.5h sessions on each day, with Q&A sessions and a break in between


  • Kerry Osborne, Randy Johnson, Andy Colvin from Enkitec
  • Tanel Poder from right here :-)

All of the speakers are hard-core hands-on professionals, having worked on many different real-life (production) Exadata environments of their clients. Enkitec dudes didn’t stop there, they bought a half rack for themselves, just for playing around with it. Yeah (+1 from me), some people buy a red hot Ferrari, some buy a red hot computer rack with an X on it :-)


  • 375 USD (early bird until 22. July), 475 regular price

More information, abstracts and registration:

I don’t think you’ll find an Exadata learning opportunity like this from anywhere else (and any time soon), especially considering the price!

This conference is so hot, that one of the attendees managed to sign up to it even before I had published this page to the world! :-)

Tech Reviewer, Tech Reviewer! ;-)

I just noticed that Jonathan Lewis has announced that he’s writing a new Oracle (fundamental) internals book, due to be out in November.

So, I’m happy to add to Jonathan’s announcement, that I’m the tech reviewer of that book!

After all the hard work on the Exadata book, I didn’t want to hear about working on any book again (even if it’s just tech reviewing work), but as this is Jonathan’s book, about exactly these topics I love and focus on, I had no choice but to make an exception and become a reviewer ;-)

I’ve already reviewed a couple of chapters and this book is going to be awesome!


IOUG Select Journal Editor’s Choice Award 2011

In May I received the IOUG Select Journal Editor’s Choice Award for my Systematic Oracle Latch Contention Troubleshooting article where I introduced my LatchProfX tool for advanced drilldown into complex latch contention problems (thanks IOUG and John Kanagaraj!).

As the relevant IOUG webpage hasn’t been updated yet, I thought to delay this announcement until the update was done – but I just found an official enough announcement (press release) by accident from Reuters site:

Woo-hoo! :-)

The article itself is here:

Thanks to IOUG crew, John Kanagaraj and everyone else who has read, used my stuff and given feedback! :-)

Backups are forever

You should save this link in your bookmarks, for the next time you accidentally remove your database’s online redologs or overwrite some ASM disks:


Delayed Block Cleanout / ORA-01555

Here is a link to a collection of scripts that can be used for some entertainment (well, it probably depends on your personal definition of "entertainment"...) regarding "Delayed Block Cleanout". These scripts are meant to be used in a playground environment - do not attempt to get them close to anything important as they might have some undesirable side-effects. Please read the comments in the file header description before attempting to run them.

Reminder and Public Appearances 2011

First, a reminder – my Advanced Oracle Troubleshooting v2.0 online seminar starts next week already. Last chance to sign up, I can accept registrations until Sunday :-)

I won’t do another AOT seminar before Oct (or Nov) this year. More details and sign-up here:

I have rescheduled my Advanced SQL Tuning and Partitioning & Parallel Execution for Performance seminars too. I will do them in September/October. Unfortunately I’m too busy right now to do them before the summer.

Public Appearances:

  • I will be speaking at the UKOUG Exadata Special Event in London on 18th April
  • I have submitted a few papers for Oracle OpenWorld in San Francisco as well (end of Sep/beginning of Oct), all about Exadata. Let’s see how it goes, but I’ll be there anyway, which means that I’ll probably show up at the Oracle Closed World event too!

And that’s all the travel I will do this year…

Virtual Conferences:

I’ll soon announce the 2nd EsSN virtual conference too ;-)

Free online stuff:

Perhaps in a month or so I will do another hacking session (I’ll plan 2 hours this time, 1 hour isn’t nearly enough for going deep). The topic will probably be about low-level details of SQL plan execution internals… stay tuned!

Latch contention troubleshooting case study and Flashback Database performance issues with LOBs

Steve Bamber has written up a case study of library cache latch contention troubleshooting of an Apex application with LatchProf. I’m happy that others also see the value and have had success with my new LatchProf based latch contention troubleshooting approach which takes into account both sides of the contention story (latch waiters and latch holders/blockers) as opposed to the guesswork used previously (hey if it’s shared pool latch contention – is must be about bad SQL not using bind variables …. NOT always…)

Anyway, I’m happy. If you have success stories with LatchProf, please let me know!

As a second topic of interest, Laimutis Nedzinskas has written some good notes about the effect and overhead of Flashback Database option when you are using and modifying (nocache) LOBs. We’ve exchanged some mails on this topic and yeah, my clients have sure seen some problems with this combination as well. You basically want to keep your LOBs cached when using FB database…