Smart Scan enhancements in Oracle Exadata 12c-inline LOBs

As part of the 12c release of the database and cellos Oracle introduced the ability to perform Smart Scans on inline LOBs. The enhancement is certainly for Secure Files only. And as always, if you would like to read up about Secure Files you can head over to Tim Hall’s website for the details.

To demonstrate the new behaviour I have used an BP 22 database on Exadata 11.2.3. (more...) fails with Unable to locate any IB switches

With the release of Exadata X5 Oracle introduced elastic configurations and changed the process on how the initial configuration is performed. Back before you had to run which would go across the nodes and change all the settings according to your config. This script has now evolved and it’s called which is part of OEDA (onecommand). During one of the recent deployments I ran into the below problem:

[root@node8 linux-x64]# ./applyElasticConfig. (more...)

How to configure Link Aggregation Control Protocol on Exadata

During a recent X5 installation I had to configure Link Aggregation Control Protocol (LACP) on the client network of the compute nodes. Although the ports were running at 10Gbits and default configuration of Active/Passive works perfectly fine the customer wanted even distribution of traffic and workload across their core switches.

Link Aggregation Control Protocol (LACP), also known as 802.3ad is a methods of combining multiple physical network connections into one logical connection to increase (more...)

Exadata Fast Data File Creation

This post is the result of some testing I performed on Exadata data file creation. You may know that Exadata offloading incorporates SQL optimisations as well as some infrastructure work. For quite some time Exadata allowed the DBA to create data files a lot quicker than on traditional systems. This has been documented before, for example by @mpnsh here

The final comment on his blog entry was a remark that data file creation is quite (more...)

#C15LV Collaborate’15 updates!!

Hi All, Last week, I registered my presence at Collaborate’15 in Las Vegas as a speaker, attendee and at Oracle demo booth duty. It was an awesome experience meeting some polished brains and smart minds. After the first day of registration, I attended the #DBIM12c session by Maria Colgan, #DB12c Multitenant by John McHugh and #Exadata session … Continue reading

Oracle Exadata Performance: Latest Improvements and Less Known Features

Here are the slides of a presentation I did at the IOUG Virtual Exadata conference in February. I’m explaining the basics of some new Oracle 12c things related to Exadata, plus current latest cellsrv improvements like Columnar Flash Cache and IO skipping for Min/Max retrieval using Storage Indexes:

Note that Christian Antognini and Roger MacNicol have written separate articles about some new features:



Exadata Storage Index Min/Max Optimization

Before discussing the Exadata-specific feature, let’s review what the database engine can do independently of whether Exadata is used. To execute queries containing the min or max functions efficiently, two specific operations are available with B-tree indexes defined on the column referenced in the min or max function. The first, INDEX FULL SCAN (MIN/MAX), is used when a query doesn’t specify a range condition. In spite of its name, however, it performs no full (more...)

Exadata Documentation Available

Please join me in welcoming the Exadata product documentation to the internet. It’s been a long time coming, but glad it’s finally made an appearance!

Exadata 12c New Features RMOUG Slides

I've finally gotten around to post my RMOUG Slide Deck on Slideshare. Hopefully this is helpful to folks looking at new features in Exadata.

Exadata & In-Memory Real World Performance Artikel (German)

Heute wurde auf "" ein aktueller Artikel von mir veröffentlicht. Es geht darin um die Analyse eines Falles bei einem meiner Kunden, der auf Exadata nicht die erwartete Performance erreicht hat.

In dem Artikel werden unterschiedliche Abfrage-Profile analysiert und erklärt, wie diese unterschiedlichen Profile die speziellen Features von Exadata und In-Memory beeinflussen.

Teil 1 des Artikels
Teil 2 des Artikels

Want to learn Exadata ?

Many people have asked me this question that how they can learn Exadata ? It starts sounding even more difficult as a lot of people don’t have access to Exadata environments. So thought about writing a small post on the same.

It actually is not as difficult as it sounds. There are a lot of really good resources available from where you can learn about Exadata architecture and the things that work differently from any non-Exadata (more...)

Oracle Bundle Patching

I’ve spent a few days playing with patching with the so called “Database Patch for Engineered Systems and Database In-Memory”. Lets skip over why these not necessarily related feature sets should be bundled together into effectively a Bundle Patch.

First I was testing going from to BP2 or Then as soon as I’d done that of course BP3 was released.

So (more...)

UKOUG Tech14 slides – Exadata Security Best Practices

I think 2 years is long enough to wait between posts!

Today I delivered a session about Oracle Exadata Database Machine Best Practices and promised to post the slides for it (though no one asked about them :). I’ve also posted them to the Tech14 agenda as well.

Direct download: UKOUG Tech14 Exadata Security slides

The Importance of the In-Memory DUPLICATE Clause for a RAC System

With the INMEMORY clause you can specify 4 sub-clauses:

  • The MEMCOMPRESS clause specifies whether and how compression is used
  • The PRIORITY clause specifies the priority (“order”) in which the segments are loaded when the IMCS is populated
  • The DISTRIBUTE clause specifies how data is distributed across RAC instances
  • The DUPLICATE clause specifies whether and how data is duplicated across RAC instances

The aim of this post is not to describe these attribues in detail. Instead, (more...)

Exadata Shellshock: IB Switches Vulnerable

Andy Colvin has the lowdown on the Oracle response and fixes for the bash shellshock vulnerability.

However, when I last looked it seemed Oracle had not discussed anything regarding the IB switches being vulnerable.

The IB switches have bash running on them and Oracle have verified the IB switches are indeed vulnerable.

[root@dm01dbadm01 ~]# ssh

root@'s password:

Last login: Tue Sep 30 22:46:41 2014 from


Exadata and Bash Shellshock

There has recently been a lot of news about the exploit revealed in the bash shell.  While the fix is very quick to implement, there are a couple of tricks that are required to install this update on an Exadata environment.  According to Oracle support note #1405320.1, Exadata storage server versions 11.2.3.x.x and 12.1.1.x.x are susceptible to the exploit.  On a typical Oracle Enterprise Linux, a simple (more...)

Exadata: What’s Coming

This is based on the presentation Juan Loaiza gave regarding What’s new with Exadata. While a large part of the presentation focussed on what was already available, there are quite a few interesting new features that are coming down the road.

First of was a brief mention of the hardware. I’m less excited about this. The X4 has plenty of the hardware that you could want: CPU, memory and flash. You’d expect some or all (more...)

Clobbering grub.conf is Bad

I’m sharing this in the hope of saving someone from an unwelcome surprise.


I recent upgraded an Exadata system from to Apart from what turns out to be a known bug[1] that resulted in the patching of the InfiniBand switches “failing”, it all seemed to go without a snag. That’s until I decided to do some node failure testing…

Having forced a node (more...)

The point of predicate pushdown

Oracle is announcing today what it’s calling “Oracle Big Data SQL”. As usual, I haven’t been briefed, but highlights seem to include:

  • Oracle Big Data SQL is basically data federation using the External Tables capability of the Oracle DBMS.
  • Unlike independent products — e.g. Cirro — Oracle Big Data SQL federates SQL queries only across Oracle offerings, such as the Oracle DBMS, the Oracle NoSQL offering, or Oracle’s Cloudera-based Hadoop appliance.
  • Also unlike independent (more...)

21st Century DBMS success and failure

As part of my series on the keys to and likelihood of success, I outlined some examples from the DBMS industry. The list turned out too long for a single post, so I split it up by millennia. The part on 20th Century DBMS success and failure went up Friday; in this one I’ll cover more recent events, organized in line with the original overview post. Categories addressed will include analytic RDBMS (including data (more...)