I am back

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It's been a very long time not coming here, about 2 years and half ... and I missed it big time.

Now I moved to Oracle Systems (formerly Sun Microsystems) on a role support-programmer mixed, within RPE (Revenue Product Engineering) on the Extra Care team, with focus on Solaris, Engineered Systems with Solaris, ZFS Storage Appliance and Ops Center. I'm very happy since my job is closer to development, something was looking for since some years now.

A cycle closes, full of good experiences, learnings and miles!!! lots of miles, hotel nights, Engineered Systems installations and migrations!

Went up and down, all over the continent, helping customers to adopt Exadata, Exalytics and SuperCluster . Was a very exciting time, meeting very interesting people within Oracle and outside!

What's ahead of the road? since less travel will mean more time available, you may expect more new content here! fresh, maybe with different perspective now that I'm getting into the inner workings of Solaris/Linux and storage.

I'm very excited and looking forward to resume contributing a little to this huge sea of knowledge!!!

Stay tuned!

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Book Review - High Performance MySQL 3rd Edition

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This is THE MySQL performance book. Period!

Every chapter is very well crafted, with a precise balance between theory and practice, and full of invaluable nuggets, sometimes transcending the MySQL arena and applicable to any database! Such cases are Chapter 2-Benchmarking MySQL and Chapter 3-Profiling Server Performance, very solid foundations for the reading ahead.

All over the text, authors propose tools, examples of use and proven diagnostic techniques, that will greatly improve your performance firefighter skills and enhance your knowledge of MySQL internals. Nevertheless, what I liked the most from this book is taking into consideration the physical part of database structures in play when speaking about performance, which is something most authors don't include; plus treatment on MySQL high availability and cloud features, which we'll increasingly see on customers.

As you may know, MySQL architecture relies on what is called “Storage Engines” and this book provides resolution down to that level, describing behavior, pros and cons among each major storage engine, plus some improvements coming for MySQL 5.6 (now in beta stage). That is cool!!!

However, there is something that kind of bugged me at times and was references to a specific commercial MySQL offering and tools, but after taking a look to that company web-site, found that is a great contributor to the MySQL community and you can actually use the tools!

At the O'Reilly website you can take a look to the book's TOC, bet you will find it very complete; hey! you can even peek the content with Google Preview, just follow the link: High Performance MySQL

If you are interested on Mathematical Rigorous methods for performance tuning see Performance Enlightening - The Craig Effect (Tropa de Elite)

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Performance Enlightening - Craig Effect (Tropa de Elite)

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During the past week I had the opportunity to assist both the Oracle Performance Firefighting and the 

Advanced Oracle Performance Analysis and only can say: awesome!!!

Craig Shallahamer is a great teacher and has a lot of resources to effectively share knowledge, even if 

the subject is complex like buffer cache structures or arid like the mathematical foundation required for 

perf analysis. That is not all, he provides valuable tips of the trade or anecdote nuggets, dipped on a 

very fresh and sometimes humorist perspective.

The result: we started searching for those AWRs and Statspack reports that were difficult to analyze, I even 

recalled some unsolved performance cases that stained my record; difference now, is we all have the 

analytical elements to properly handle these and new challenges.

Here a group picture of "The Elite Squad" (Tropa de Élite)

Sao Paulo, Brazil / March 19th-23th 2012

 If you want to know more about these trainings or get more insight on Craig's methodologies and research, please click 

the image below (a new window will show up, you may need to allow this pop-up).

Go to OraPub.com

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Book Review - iOS 5 Programming Cookbook

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You will write iOS apps in less than you think

Being a C/BASIC hardcore programmer for mobile devices in a past life, I enjoyed very much this book because it really helped me grasp quickly many basic and intermediate topics on iOS 5 Objective-C programming, would say after reading the full book I have all needed to program good basic applications; and even after getting practice and experience, guess I will eventually resort on this book as reference. In my opinion this book is awesome and a must for beginners and intermediates.

Honestly, I consider myself not very much fan to the Cookbook format, however this is one case where the author, Vandad Nahavandipoor, exploits it wonderfully to show and develop case after case of what you will face as an iOS programmer, both for iPad and iPhone! He misses nothing and includes good explanations and concise screenshots when needed.

Now, the table of contents covers almost everything is needed to develop any type of application: Location & Maps, Networking, Audio & Video, plus some “must-have” topics like Multitasking, Graphics & Animations or Core Motion. My favorite chapter is #2, because it provides the building blocks for GUI programming, including corresponding source code examples!

Something I would like to see is bluetooth or network programming basics, but maybe I'm overreaching and those are advanced topics, out of the scope if this book.

If you want to take a closer look go to the Product Page at O'Reilly website: iOS Programming Cookbook - Book I'm sure you will get interested!


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Who is using your Undo space? - Improved Script

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Hi folks!
I have extended the Undo usage scripts to include two additional indicators:
1) undo change vector size statistics
2) Used undo records/blocks

and support for RAC infrastructure, so you can spot the hungriest UNDO eaters for any given instance.

Then the script for Oracle 11g is as follows:

set pagesize 400
set linesize 140
col name for a25
col program for a50
col username for a12
col osuser for a12
SELECT a.inst_id, a.sid, c.username, c.osuser, c.program, b.name,
a.value, d.used_urec, d.used_ublk
FROM gv$sesstat a, v$statname b, gv$session c, gv$transaction d
WHERE a.statistic# = b.statistic#
AND a.inst_id = c.inst_id
AND a.sid = c.sid
AND c.inst_id = d.inst_id
AND c.saddr = d.ses_addr
AND a.statistic# = 284
AND a.value > 0
ORDER BY a.value DESC

If you want to run this script on versions 10g1 and 10g2, just replace the statistic# with 176; 216 if your database is 11gR1... or use the following version independent script!!! (Hope we don't change the statistic name).

set pagesize 400
set linesize 140
col name for a25
col program for a50
col username for a12
col osuser for a12
SELECT a.inst_id, a.sid, c.username, c.osuser, c.program, b.name,
a.value, d.used_urec, d.used_ublk
FROM gv$sesstat a, v$statname b, gv$session c, gv$transaction d
WHERE a.statistic# = b.statistic#
AND a.inst_id = c.inst_id
AND a.sid = c.sid
AND c.inst_id = d.inst_id
AND c.saddr = d.ses_addr
AND b.name = 'undo change vector size'
AND a.value > 0
ORDER BY a.value DESC

Read the popular 2008 article Who is using your UNDO space?

Interested on MySQL Performance? Read  Book Review - High Performance MySQL


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First pervasive-post

Today I'm writing this post from a Samsung Galaxy, my hand sized tablet, camera included, microphone and lots of fun.

I have been busy this year and that is thanks to the tremendous success of the Database Machine/Exadata.

Traveled all over the caribbean and south america, plus my first OOW experience as Oracle employee: always exciting!

Bandeja Paisa / Paisa "tray" - Medellin, Colombia


Sao Paulo Subway System

Oracle Open World 2011

The Oracle Exadata: latest Business Weapon

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Sorry I’ve been having a lot of work installing, maintaining and migrating to Database Machines all over Latinamerica for the latest 10 months; that means lot of travels abroad, all of them very exciting, but the real excitement comes from my job working with this wonderful Machine.

Was on the last project when realized how important is this investment for our customers, having this big caribbean Telco installed their first Exadata and later migrated their databases meant for them dramatic performance improvements and the ability to get more up-to-date analytical information and compete better and more agile.

Of course the Database Machine fulfilled expectations when we achieved a processing reduction of 6x on their nightly batch processes, going from 8-9hrs processing time, down-to 1.5-2hrs processing time. What this means: now they’re able to increase the refreshing time of their analysis tools 12 times a day and on demand, instead of having latest information one day behind.

Read my related article on Exadata Hybrid Columnar Compression

My steps to implement EHCC

Recommended reading on My Oracle Support notes that helped make this happen:

Migrating to Oracle Exadata Storage Server Paper (PDF)

Oracle Sun Database Machine Performance Best Practices [ID 1067520.1]

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