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Advertorial: upcoming appearances

I’ve got a few speaking commitments in the next few months, which might be of interest to you:

Planboard DBA Symposium

This conference is held in Utrecht, NL on the 12th of June. Some of the speakers include: Alex Nuijten and Rob van Wijk. I’ll be presenting about multiblock reads, and try to explain some of the differences which where silently introduced with Oracle version 11.

Enkitec Extreme Exadata Expo (E4)

Enkitec recently completed its 80th Exadata implementation, so this is a good time to announce that we are organizing the first Enkitec Extreme Exadata Expo (E4) on 13-14. August 2012, in Dallas, Texas!

IOsaturationtoolkit-v2 with Exadata IORM and AWESOME text graph

I’ve got a new version of IOsaturation toolkit which you can download here and it has a cool script called “smartscanloop” that shows you the Smart Scan MB/s per database across the Exadata  compute nodes.. it’s a per 2secs sample so that’s a pretty fine grained perf data and near real time text graph. Very useful for doing IORM demos and monitoring what database is currently hogging the IO resources and since it’s presented in a consolidated view you don’t have to go to each Enterprise Manager performance page and have a bunch of browser windows open.

MOATS-like sqlplus “top” utility for RAC


So, you think MOATS was cool?! Check this out by Jagjeet Singh :)



Here’s a final warning of the busy time I’m having next week. It starts with the E4 conference in Dallas (full  agenda here),my topic is “Due Diligence examining Exadata”.  Then it’s on to Minneapolis where I’ll be doing a one-day event on finding and reading Execution Plans (Agenda andRegistration).

Oracle’s Timeline, Copious Benchmarks And Internal Deployments Prove Exadata Is The Worlds First (Best?) OLTP Machine – Part I

I recently took a peek at this online, interactive history of Oracle Corporation. When I got to the year 2008, I was surprised to see no mention of the production release of Exadata–the HP Oracle Database Machine. The first release of Exadata occurred in September 2008.

Once I advanced to 2009, however, I found mention of Exadata but I also found a couple of errors:

Critical Analysis of “Critical Analysis Meets Exadata”

Kevin Closson put out a post yesterday called Critical Analysis Meets Exadata, linking to two awesome videos. It’s well worth spending the time to watch these, even if (like me) you never get so much as a sniff of Exadata. :)

I was lucky enough to be one of several people asked to review these videos before they were released. I’m sure some of the performance gurus on the Oak Table had a lot to say, but of the several comments I fed back to Kevin, I would just like to post a couple here:

Critical Analysis Meets Exadata

If you are trying to find out more in-depth information on how Exadata architecture really works, I’m offering this video presentation to offer some critical thinking on the matter. It is broken into two segments. I do recommend watching both.

Critical Analysis Meets Exadata – Part I

Critical Analysis Meets Exadata – Part II

Exadata Smart Scan predicate offloading and sequence.NEXTVAL

There was a question in the twitter-sphere about whether using sequences (sequence.NEXTVAL) in your select query’s projection list would somehow disable smart scans happening?

The answer is no, sequence use with smart scans works just fine. The smart scan offloading applies to data retrieval row sources (and filtering) only and nothing else. So, what you have in the query’s projection list (the sequence use for example), does not directly affect the smart scan decision. Just like any other operations like sorting, grouping etc, do not have anything to do with smart scans and don’t disable their use. Smart scans are only related to data retrieval and any other operations do not affect them.

Exadata experience, what does that actually mean?

As an active member of the Oracle user community I really enjoy talking to delegates at user conferences and user group meetings. As such I was very lucky having had the opportunity to attend two of them recently. I have written about the OUGN spring conference in the post before this, and I also enjoyed the AIM meeting earlier in March.

One of the subjects that always seems to come up is Exadata. Many, many DBAs want to have Exadata experience, and if only to tick a box. Now Exadata means a significant investment, in other words not every company on the planet will have one. On the other hand it’s reasonably complex to administer, therefore recruiters and other HR personal are very interested in DBAs with “Exadata experience”. Now, the reason of this blog post is an open question to the readers: what do you consider as Exadata experience?