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Exadata

Enkitec Extreme Exadata Expo (E4) 2013 – Call for Papers

Enkitec E4, the only exclusively Exadata-focused conference in the world, is going to be back this this year too! :-)

It will take place on 5-6 August 2013 in Four Seasons Hotel & Resorts in Irving, TX. It will be very hot in Texas then, but the hotel has a really cool pool there (which I intend to be able to use this year – last year I had to spend all my free time working in the hotelroom unfortunately). And they have beer inside too :)

There will be very good speakers showing up this year too (including the keynote speaker who’s awesome, but I can’t say the name yet) and I’ll hang out there too. I think I’ll deliver a live demo / internals hacking session this year (that way I don’t have to spend my night before the conference preparing slides and can focus more on the cool stuff).

Exadata Smart Scan Projection Limitation

Here is an interesting limitation to Exadata Smart Scans - if more than 254 columns from a table (not HCC compressed, more on that in moment) need to be projected, Smart Scans for that particular segment will be disabled and Exadata will fall back to conventional I/O.

New Exadata Prototype

I got a look a new prototype for the next generation Exadata last week while doing some work with a company in Europe. Apparently there is a big push to be environmentally friendly there now and so Oracle is trying to come up with a model that uses less power and is biodegradable. The word on the street is that it won’t be available until after release 2 of the 12c database.

The new model has a few drawbacks though. For one thing, it only lasts a few weeks before you must either replace it or higher some rocket surgeon consultants to come in and tune it. From the early version of the prototype I saw, it does appear to be smaller and more tasty than previous models though.

 

 

Oracle 11.2.0.1 and the ‘kfk: async disk IO’ wait event

Recently I was discussing some IO related waits with some friends. The wait I was discussing was ‘kfk: async disk IO’. This wait was always visible in Oracle version 11.2.0.1 and seems to be gone in version 11.2.0.2 and above. Here is the result of some investigation into that.

First: the wait is not gone with version 11.2.0.2 and above, which is very simple to prove (this is a database version 11.2.0.3):

HOWTO: Viewing XML data in V_$CELL_% storage cell SYS views

Got a small question from Frits if I could help him make some XML data readable in one of the SYS.V_$CELL_% / V$CELL_% views. I have been a bit busy, in between jobs, to try to make some of those XML columns more readable anyway (for myself and others) so…lets have a go at it. …

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Storage Indexes vs Database Indexes Part II: Clustering Factor (Fast Track)

Two posts in two days !! Well, with Christmas just around the corner, I thought I better finish off a couple of blog posts before I get fully immersed in the festive season The Clustering Factor (CF) is the most important index related statistic, with the efficiency of an index performing multi-row range scans very much […]

Storage Indexes vs Database Indexes Part I MIN/MAX (Maxwell’s Silver Hammer)

It’s often stated that in Exadata, you don’t need conventional database indexes anymore as everything runs so damn fast that indexes are simply a waste of time and space. Simply drop all database indexes and things will run just as fast. Well, not quite … There are many many scenarios where database indexes are still […]

Exadata Storage Indexes Part V: Warming Up (Here Come The Warm Jets)

As I mentioned in a previous post, there are a number of Similarities between Storage Indexes and Database Indexes. One of these similarities is the “warming up” process that needs to take place before indexes become “optimal” after either the Storage Server (in the case of Storage Indexes) or the Database Server (in the case […]

Enkitec at UKOUG 2012

Hi,

Here’s the list of Enkitec’s UKOUG conference sessions – I will be delivering 3 sessions, including a 2 hour Exadata hacking session!

We are also sponsoring the ping-pong table (woo-hoo! :) and will give away 3 super-cool Sphero balls … that should be fun! ;-)

See you soon!

 

Exadata Storage Indexes Part IV – Fast Full Table Scans (Speed of Life)

OK, let’s look at Storage Indexes in action. But first, following is the setup for the various demos to come. I basically create one table called BIG_BOWIE that’s about 1GB in size and then simply create another table called DWH_BOWIE where the contents of this are re-insert into itself a few times to get to about […]