Wheeew, I am now a RedHat Certified Engineer!

A couple of weeks ago, RedHat announced the general availability of RHEL6… also effective on this release is the change on their certification offering. RHCT will now be replaced by RHCSA (Red Hat Certified System Administrator), and if you would like to be RHCE on RHEL6 regardless of your certification on RHEL5 you still have to go through the RHCSA exam.. and then once you pass.. you are then allowed to take RHCE exam for RHEL6. More details here: RHCSA, RHCE

Since my self study modules/materials are on RHEL5, and it would take a while for the RHEL6 exam (more...)

I’ll be speaking at HOTSOS 2011!

Hotsos is an annual conference that is devoted on Oracle system performance and the people presenting there are really passionate about their research and highly specialized about their subject area. Kinda geeky, but hey, performance is never boring.. and for me there’s still a lot of things to learn on each of the areas of performance and these are as follows: 
  • Application Testing
  • Benchmark
  • Capacity Planning
  • Database Tuning
  • Hardware and OS
  • Performance Tools
  • SQL Tuning
  • Troubleshooting & Internals

Yesterday, I received an email that I have been accepted as a presenter for Hotsos 2011 ;) this is really cool .. !

My presentation (more...)

After OOW, my laptop broke down – data rescue scenario

I just got back in the office from a 2 week conference + vacation (SFO,WAS,NY). Then I was finally back in shape to work and do the usual geek stuff again but suddenly my Neo laptop suddenly stopped working! (the one I mentioned here, but it’s now on Fedora)

It can’t even boot to BIOS, certainly a case worse than BSOD.

So after fiddling with the laptop and systematically ruling out other component failures (power cable,monitor,memory,HD), Yes it’s much like troubleshooting an Oracle database! … we decided to bring it to the service center.

But wait! it may (more...)

Oracle Closed World and Unconference Presentations

There are so many things to blog about these past few days. That is mainly about the cool stuffs around OCW and OOW, sessions that I have attended (OCW, unconference, OOW), plus the interesting people that I’ve met on various areas of expertise.. So I’ll be posting some highlights (and a lot of photos) on the next posts.

Last Monday (Sept. 20) I was able to present at the Oracle Closed World @ Thirsty Bear. The full agenda is here http://www.amiando.com/ocw.html?page=434169

I did my presentation after Tanel’s live hacking session. There were 30 (+-5) attendees and (more...)

OOW 2010 – the highlights

I started my week with a blast by sky diving at Parachute Center – Sacramento, it was an awesome experience!

Then we went to Redwood Shores to check out the Oracle office

Then headed back to the Moscone area to register and attend the sessions

On the way to the 3rd floor to get the conference materials I saw a familiar face.. yeah it’s my friend Craig Shallahamer! finally we’ve met.. and we had a long talk & catching up about performance related stuff before his talk about troubleshooting “free buffer waits” at 3pm

On the “RAC customer panel” (more...)

OOW 2010 – my schedule



I was able to finalize my schedule a week before the OOW 2010 and most of the sessions that I’ll be attending are related to Performance & Exadata.

So that would be:

You can check my detailed schedule below … (I know it’s a jam-packed sched! I hope I can go to all of them..)

This will be my first time attending the OOW and I’m sure I’ll be having a superb time ;) I’m registered as a Blogger so I got (more...)

Statistically summarize Oracle Performance data

Here’s the draft of this post http://karlarao.tiddlyspot.com/#dbms_stat_funcs , expounded version coming up! :)


Guesstimations

We do Guesstimations (calculated or not) once in a while… and this is an interesting read about it…

http://3quarksdaily.blogs.com/3quarksdaily/2008/09/useless-calcula.html

In the Oracle side… we also use this back-of-the-envelope-calculations for coming up with man-days, capacity planning, hardware recommendations, or just simply knowing what’s happening. And I like these phrases from the article…

“But how can we know the actual figure? We cannot. We can only get closer and closer approximations by measuring things more and more accurately (the volume, not just of the building, but of everything in it, which must be subtracted). It’s not like there’s an (more...)

Graphing the AAS with Perfsheet a la Enterprise Manager

On this previous blog post I was able to take advantage of the AWR repository particularly the DBA_HIST tables to have a far better workload information and nice correlation of the Database Server’s Capacity, Requirements, and Utilization on a single output… and yes… easily going through all the SNAP_IDs!

Having this info made it easier for me to notice trends (text or visualization) and play around with the data (some statistics out of it)… which I can say a big help on finding the root cause of the problem (here and here)

Before going any (more...)

Oracle datafile IO latency – Part 1

On my post about observing the Exadata V1 I had an interesting comment posted by Mark Seger (author of collectl and collectl utilities) about the correlation of activities across a system, the sample and snap time, and seeing the state of the subsystem before and after

The comment made me curious about the effect of snap intervals on the performance numbers of the datafiles and block devices.. especially on the latency numbers.. so I made a few test cases and created some scripts that would give me 5 seconds, 10 minutes, and 60 minutes output of (more...)

The “Not a Problem” Problem and other related stuff

It’s been a while since I visited the Sun Video RSS feed and I found some interesting videos related to performance that are worth sharing and something you could watch over a big cup of coffee..

First is titled Performance: The “Not a Problem” Problem which I could also relate when doing performance analysis for example…

  • When a client instantly jump into conclusion that the performance degradation is caused by the database link well in reality when everything is measured/profiled it turned out that it’s because of the slow IO subsystem..
  • Or when the Data Guard environment was being blamed (more...)

Oracle Mix – OOW 2010 Suggest-A-Session

I hope it’s not too late. I just finished my Suggest-A-Session on Oracle Mix titled “Mining the Oracle Database AWR repository for Capacity Planning“, this might be of interest to you… below is the abstract:

“New CPUs and storage arrays, they are getting faster but these resources are finite and come at a cost. Hence, capacity planning plays a very important role to ensure proper resources are available to handle expected and unexpected workloads. Another critical matter for the DBAs and IT managers is justifying the expense of adding resources on the system. With guesswork you’ll end up (more...)

Seeing Exadata in action



Last week I was able to attend a 3 day exadata workshop conducted by performance engineers from Singapore. It was supposed to be a 5 day workshop with hands on labs but everything was squeezed (unfortunately no hands on) and just the critical sections were tackled.. The workshop highlight was the demos and these are as follows:

- loading large amount of data from an external table
- cell offloading on a typical datawarehouse query
- creation of a 400gb tablespace
- linear scalability of storage cells

Although all of these demos were done on Exadata Version (more...)

My Personal Wiki – karlarao.tiddlyspot.com




Our brain does not work in a linear or list-like manner (yeah.. not like the guy on the right). From the textbooks and blogs that we read everyday we are all aware that print is laid out in a series of lines or rows…

but our brain is multidimensional…

the information as it is being absorbed could be travelling sequentially to our brain, but internally it is not being serviced in simple lists and lines. There is a complex process of sorting and selecting and the whole network of words and ideas are being juggled and interlinked in order to (more...)

“Ideas build off ideas”… making use of Social Networking sites

OracleUsersPh

In this post (which has been looong overdue :p ) I’ll show you how you could make use of Social Networking Sites to make knowledge sharing and meeting people more fun. As you can see from the illustration above, I’ve made use of the following sites/services to build a dynamic and multidimensional means of communication:

  • Facebook
  • Twitter
  • FeedBurner RSS
  • FeedBurner Mail Subscription
  • Google Sites
  • LinkedIn

The story behind it…

I am a DBA for 4years+, and started with zero knowledge about Oracle. I joined SQL*Wizard, which has a great training program and exposed me to a lot of difficult (more...)

DEVCON Luzon 2010

I just recently I became a member of the PSIA Tech Council… The company I’m working for is a member of PSIA which makes up 90% of the country’s software sector promoting the growth and global competitiveness of the Philippine software industry, also an active partner of the government and academe in implementing programs that benefit the industry.

The PSIA, PSIA Tech Council, together with the Awesome and Cool sponsors will be having the Luzon leg of DEVCON here in Manila!

Below are the details of this awesome event:

09 February 2010, 4-9pm, SMX Convention Center Function (more...)

Craig Shallahamer is now blogging!

Craig Shallahamer is now blogging… check out his initial post here!

Earlier I had a few mail exchanges with him and got to check his new work.. called the Stress Identifier. Hmm.. so how it will be helpful? Well if you have already characterized your workload, you may want to definitively determine which internal database activity is stressing your CPU, IO, and network subsystems. So this tool will avoid the guess work of selecting that “unit of work”… check out the link for more details…

And most of all.. grab a copy of his new book Oracle Performance Firefighting (more...)

Workload characterization using DBA_HIST tables and kSar

Been busy these past few days..

Well, this post is about taking advantage of the built in data store that started in 10gR1.. yeah it’s AWR, and it’s very much like a “Statspack on steroids” (got that from Kyle Hailey’s modules). What’s exciting about 10g and above is we could utilize the “Time Model” and the OSSTAT view and use them together with the SYSTAT view to have a far better workload information when going through all the SNAP_IDs.

I have this “little” issue before of getting lazy when generating multiple AWR reports… yeah it’s just so daunting, you’ll get (more...)

50+ SQL Performance Optimization scenarios

Before the year ends I’d like to share some good stuff…

I have never seen a huge compilation of SQL tuning tips or rewrite scenarios (with test cases) and got them only on OracleFans forum… ooops… so you can’t read Chinese? try this translated version, whew.. good thing Google has this translate service that I am able to read in Chinese.. :)

So how did I end up on this forum? mm… I can’t really remember… I’m a curious wayward Googler, either I was having problems on a particular SQL on a client or I’m getting really curious about SQL (more...)

RAC system load testing and test plan

Yesterday I was browsing through some docs in Metalink regarding RAC on Windows… then again came across the “RAC Starter Kit and Best Practices” notes…

RAC Assurance Support Team: RAC Starter Kit and Best Practices (Generic) (Doc ID 810394.1)
RAC Assurance Support Team: RAC Starter Kit and Best Practices (Windows) (Doc ID 811271.1)

On the Generic note, just recently they’ve uploaded a new version of the RAC System Load Testing white paper… you can also find on the attached docs the RAC System Test Plan

Both of these docs are good stuff.. we all know that critical (more...)