"Hotsos Revisited", Revisited…

 Lucas already gave a very good in depth overview of the "Hotsos Revisited" session last night. It always amazes me how fast he can make a cool blog post that  accurately points out the impressions we had of the evening. It started off with an idea we (Jeroen, Toon, Gerwin and me) had  of sharing some of the ideas, atmosphere and presentation info we got from the Hotsos Symposium this year. It is not an easy task to present the presenters accordingly trying to achieve some of the energy that shared during their presentations at Hotsos, also, of course, we were not that deep into the material they presented / as the people we tried to do credit to.

I am indebted  to Jeroen, Gerwin and Toon for making the time (their precious spare family time) too make it all happen. Even if it has to be all fun, you, as a presenter, don’t want to let the attendees, the audience, down by leaving them with the impression that such an evening was lost time. So it still takes a lot off effort to make it all work.

Concepts matter to me. That’s one of the reasons that I picked "Bloom Filters" as my topic, but as being stressed in time as the others, you notice that while preparing you get can get sucked into the topic far more deeply, and before I knew it I was drifting into (on Sunday night preparing) into "false positive ratio’s", hash table collisions or  "signal to noise ratio’s, significance". Although such understanding is not very useful for prepping your presentation, in this case ( ), it helps me focusing / getting into the mood.  Although you can’t control "Bloom Filter"’s in an Oracle environment, these kind of concepts help me in a better understanding off the mechanisms that are going on and have an effect on handling data / performance. One of the reasons that I have started reading Christian’s great book about "Troubleshooting Oracle Performance" (aka "TOP").

Talking about books… Toon couldn’t, of course resist, and started off his presentation to make some advertisement about his book and his up coming appearance on the planboard DBA symposym. An incentive that I gladly support. If not only, Toon did it in the humorist way only Toon can do it.

The more braver part, of his newly created presentation about the PL/SQL Hierarchical Profiler, was that he tested the Profiler and demonstrated it via applying the methodology / tool to his RuleGen application. As we Dutchies say it "met de billen bloot" demonstrated the weaker points he found, and although he already had pinpointed most of them as "points for improvement" before this test, he now actually had the proof via the PL/SQL Hierarchical Profiler. I just hope he will not suffer from "Compulsive Tuning Disorder" after he is finished tuning…

Jeroen told with great enthusiasm, exuberant and a great feeling for humor (as only the "Achterhoekers" can do) the not so easy concept of one pass distinct sampling and the enormous effort and in great detail Amit Poddar had done to present and proof the positive and enhancements Oracle had implemented via a better method for determining the number of distinct values (NDV). I greatly appreciated it that Jeroen made the time to share his enthusiasm although he could have spend the same time with his first born…

During Hotsos, Gerwin had the chance this evening to make a second attempt to show the audience an actual demo of his general approach performance profiling methodology (aka GAPP). He encountered the worsed nightmare a presenter can face, while presenting his demo on Hotsos, that his hardware / laptop broke and all his effort preparing went down the drain. Last night everything went as it should and he told in great detail the pro’s and con’s while appling GAPP on a complete architecture detecting and predicting, for instance I/O chances, performance impact culprits.

Some of the topics where not for the easy hearted as shows in the last picture and also the evening went a little in overtime. Started at 17:30 hour with a small break enjoying Chinese food, instead of 21:00 hours, we finished up after 21:30 hour. The general feeling, also from the attendees, that they / we enjoyed doing it and/or attending and these kind of sessions was an idea that should be repeated in the future.

After a lot of extra discussions while drinking some refreshments in the AMIS bar we all went home with a lot of extra info to think about and time well spend.

For all those 30+ people who attended, my thanks for attending and making the time. Thanks for the original presenters (Christian, Amit,  Bryn) for presenting those great presentations during Hotsos. We, the re-presenters, hope the attendees have enjoyed it and hope we were worthy passing those ideas and sharing the same enthusiasm, about the topics presented, Christian, Amit and Bryn did during Hotsos 2009.

In all: Thanks and till next time.

Marco