Blog Archives

Data Quality Institute

Last week I joined a small team of my colleagues at work to attend a one day seminar held by a small (non-profit) start up company called “Data Quality Institute (DQI)”, more precisely by Dejan Sarka and Uroš Godnov. The topic was an introduction to “Data Quality” from organizational and practical (technical) point of the view.

I think I first met Dejan Sarka at his course covering MS SQL Server 6.5 Administration in 1996 (or perhaps 1997?). And since then I always thought `what a pity that he took a MS SQL Server career path instead of Oracle´ :-). Of course, he’s best known as a top MS SQL Server expert, but nowadays I think his main obsession is development and application of different mathematical algorithms to achieve better quality of data stored in our relational database management systems. All demos he showed us were more or less pure SQL statements (with some helper functions written in C#) executed on MS SQL Server and the data mining methods where demonstrated with MS Analysis Services, thought it’s quite possible to recode everything for Oracle RDBMS. At present DQI doesn’t have a prepackaged product with a shiny user interface to demonstrate the power of their methodology, but this is really not their main objective at present (I think!?).

Anyway, it was a mind-boggling day for IT part of our team, that clearly showed us how weak our knowledge about Data Quality really is. Hopefully, with researches and companies like DQI things on this (often neglected) field can only get better and at the same time for the right price as well – a bad news for those overpriced software package vendors out there, I’m afraid. If you care about data quality then make sure you put DQI on your radar. We certainly did.

“Optimizing For Performance” with Jože Senegačnik

Last week I attended a four day seminar held by Jože Senegačnik. The first three days covered theoretical part and if you plan to attend the course be prepared for a hefty amount of information (720+ slides). Considering the amount of material and in-depth knowledge of Jože about Oracle performance tuning and internals, I’m positive you’ll learn something new, no matter how experienced you’re (or you might think you’re;-).
The fourth day was reserved for practical workshop. Jože prepared a test Oracle XE database instance for each participant with sample database and PL/SQL package that we needed to tune during the day. Test scenario resembled TPC-C benchmark.
Since the elapsed time could vary from PC to PC due to the different HW configuration, he told us that we should concentrate on logical I/O (LIO), so we all started with approx. 1,1 million LIO per execution of PL/SQL package, with the goal to lower the LIO under 300K (which we did at the end of the day). And here comes a shameless advert for a profiler from my side. Instead of using tkprof for a trace file analysis we used profiler.
Jože is developing and enhancing his proprietary trace file analyzer called profiler since 2002. This is a command line tool written in C that runs on Windows (I’m not sure about Unix/Linux ports) that can be used instead of tkprof. Output is a html file with correct sql hierarchy and all the necessary statistics and timings. Profiler can be purchased by course attendees for 600€ (a fair offer if you ask me, considering the amount of work put in the development of this tool by Jože). Hopefully, I’ll publish some screenshots as soon as I get my copy of the profiler.
Anyway, if you have a chance to attend this course I’m sure you’ll not regret.

SQL Developer Data Modeling

During my regular RSS feed browsing I noticed Sue Harper announcement of Early Adopter Release of Oracle SQL Developer Data Modelling tool. This is really a good news.
We used to be a vivid Designer/Developer shop in the past but we left this Oracle technology track in 6i time frame. Rightly so, considering that only Oracle (“a damage control section of it”;-) itself believes in long Developer/Designer prospect – let’s face it, both product lines are dead, we should not pretend to believe otherwise (and yes, I read Oracle white paper – State of direction and I still think the same).
What I miss the most are perhaps Designer ER modeling and Reverse Engineering capabilities. Not so long ago we tried Quest Toad Data Modeler which is not a bad tool. It’s cheap, relatively light (thought it can become a memory & CPU hog), easy to learn and use, supports all major RDBMS vendors and can do reverse engineering, but the competition never hurts.

I just downloaded Early Adopter Release and tried a few things. What to say? I do like look and feel of OSDM, but it’s too early to do a fair justice to the product. What I do know is that the price is right ;-).

Sample screenshot:

osdm

Cloud Computing

In the last WServerNews[tm] Electronic Newsletter I read interesting quote by Larry Ellison:

Quote of the Week from Oracle CEO Larry Ellison


“The interesting thing about cloud computing is that we’ve redefined cloud
computing to include everything that we already do. I can’t think of anything
that isn’t cloud computing with all of these announcements. The computer
industry is the only industry that is more fashion-driven than women’s
fashion. Maybe I’m an idiot, but I have no idea what anyone is talking
about. What is it? It’s complete gibberish. It’s insane. When is this idiocy
going to stop? We’ll make cloud computing announcements, I’m not going to
fight this thing. But I don’t understand what we would do differently in
the light of cloud computing other than change the wording of some of our
ads.” — CEO Larry Ellison at Oracle’s annual financial analysts meeting.


Bravo Larry! I think and feel the same. It’s amazing how much rubbish “IT Press Community & IT Marketing departments” are producing on the daily basis about “cloud computing”, Web 2.0, etc. Finally, one CEO who has courage to openly address this BS. Thank you Larry!

[Update on September 25th, 2009: Watch this video on Youtube.]

Windows Server 2008 – short notes from the course 6416B

I decided to attend Microsoft Official Course, 6416B Updating your Network Infrastructure and Active Directory Technology Skills to Windows Server 2008, as part of the benefit that we get from the Enterprise Agreement Contract. As a bonus, every attendee of this course got free MS Window Server 2008 Standard Edition with 5 CAL licenses (btw. this promotional offer will expire at end of the year 2008).

License for Windows Server 2008 Std. will serve me well in my home lab for both, experimenting with Oracle software on Windows OS, as well as a replacement for my venerable Windows XP workstation, allowing me to completely skip Vista.

License that I receive will allow me to run Windows Server 2008 Standard Edition as parent partition in Hyper-V, plus another instance of Server 2008 Std. as a Hyper-V child. Howard Rogers wrote about setting up his Windows Server 2008 as a workstation in not so distant blog article, thought he also find out that Hyper-V doesn’t do multimedia very well, which doesn’t bother me much, as I’ll use my “workstation” more or less for experimenting with Oracle, Windows Server 2008 itself, some writing, perhaps a bit of photo editing with Adobe Lightening ant that’s pretty much all.

I do like the look and feel of Hyper-V management, thought it bothers me the lack of support for Linux. Suse being the only Linux distribution that can use so-called synthetic (as opposed to emulated) drivers. What a shame, because I put SUSE on my “dirty-list” of Linux distributions a long time ago. If I’ll find performance of Centos 5 under Hyper-V unsatisfactory, I’ll probably replace Hyper-V with soon to be released production version of VMWare Server 2.0.

Let’s see some new features of Windows Server 2008 that are in my opinion worth spending some time studying and understanding them.


  • built-in multipath I/O and Storage Manager for SAN
  • Bitlocker drive encryption (not something I wouldn’t lightly choose for Oracle production server – but it can get handy for securing deployment of various kinds of databases on laptops)
  • services for NFS
  • Windows PowerShell – not exactly new, but it ships with Win2008 and should be one of the first features to be installed
  • brand new Windows Backup – for better or worse, Microsoft decided to redone Windows backup, completely replacing ntbackup with Windows Backup. For medium and large shops Microsoft recognizes that there are third party tools that are way better at doing backup and recovery. For a smaller shops, however, Windows Backup might be enough – I got an impression that Microsoft wanted to deliver backup tool for the dummies. Microsoft completely removed support for tape backups and added support for optical media with UDF support (in addition to disk and network drives for backup store). Limited scheduling possibilities and the fact that your only choice for a backup is complete volume (during recovery you have a chance to select files and folders, but not during backup) it’s hard to believe that many professionals will be happy with WBA. Another difference is the backup format itself, which is vhd file instead of bkf – so getting something restored is much simpler than in the old days.
  • remote differential compression – Microsoft is using this feature in new DFRS (Distributed File System Replication), allowing only changed parts of the file to be replicated – in a similar way rsync is used for a long time ;-).
  • Windows PE – Preinstallation Environment can run entirely from memory and can boot from CD, USB key – something we would have to buy from third party vendors, at least so far…
  • Windows RE – Recovery Environment – special variant of Windows PE dedicated to recovery
  • NTFS improvements – NTFS v6 brings two new features; self-healing NTFS that will reduce the need for chkdsk to run in exclusive mode and transactional NTFS with Kernel Transaction Manager
  • complete redesign of TCP/IP stack – IPv4 and IPv6 are now integrated in the tcpip.sys, they call this dual IP architecture. There are numerous improvements, especially on performance front. In older releases TCP/IP receive windows was by default fixed (at 64KB), no matter over what kind of network we communicated. With Windows Server 2008 (Vista) they introduced receive window auto-tuning that can considerably improves network performance.
  • multi CPU network interface access – in Windows Server 2003 only one CPU could access network interface – causing performance bottleneck in case if that particular CPU was overloaded, leaving little CPU cycles to handle server network traffic. In Windows Server 2008, several CPU’s can access network interface.
  • SMB 2.0 protocol allows several commands to be embedded in single packet, further enhancing network performance of high latency network connections
  • Policy based Quality of Service – network bandwidth throttling
  • Windows Remote Shell (winrm & winrs) – one “new” possibility for remote administration from command line. Network traffic is encrypted with SSL, other than that, we could do the same job with pstools from Sysinternals for years.
  • servermanager.exe – another command lined tool for administration
  • RSAT – Remote Server Administration Toolkit works on Vista and Windows Server 2008 only, unfortunately leaving vast majority of sysadmins that are still using Windows XP without this option.
  • RRAS (Routing and Remote Access Service) – has new possibility, SSTP – Secure Socket Tunneling Protocol over well known port 443
  • NAP – Network Access Protection
  • Hyper-V – it’ll be interesting to follow Microsoft success with Hyper-V, considering VM Ware decision to offer ESXi for free.
  • restartable AD Data store service
  • PHP 5.2.1support in IIS 7
  • redesign of monolithic IIS6 into highly modular IIS7
  • replacing binary IIS metastore with flexible, file based xml configuration that can be copied from machine to another machine
  • TS Gateway – TS Gateway serves as a “proxy” between client (somewhere on the Internet) and some internal TS server. TS Gateway uses port 443 and SSL encryption. Smaller shops without dedicated VPN equipment will appreciate this feature.
  • TS Remote APP – this feature is really cool. It allow us to “publish” certain applications hosted on terminal server to end users. Really neat.
  • TS Easy Print – major enhancement, we don’t need anymore printer drivers on our TS server for every printer that we have out there – instead, drivers installed on the client workstations are used
  • RDP 6.1 protocol – (available for Windows XP SP3), 32-bit color support, up to 4096 x 2048 screen size that can be displayed over several monitors, display data prioritization, single-sign on, PNP redirector, Audio Mixer …

I intentionally left out other features targeted more or less to system administration – such as Active Directory related enhancements, new deployment infrastructure (Windows Deployment Services), DNS improvements, Auditing Directory Domain Services etc.

You may ask why I didn’t mention Server Core version? Well, I believe this version in the current state is seldom usable. Certainly I wouldn’t bother to install, run and support Oracle10g/11g on this release. The major handicap of this release at present is the lack of .NET framework and hence PowerShell. I don’t expect more than 3% of Windows Server 2008 deployments will use Server Core in production. I’m afraid Microsoft released Core, at least 10 years too late to have any serious impact on enterprises that run most of their production on Windows.


Final disclaimer:
Don’t believe everything you read here. Above comments of the features are the result of my personal notes taken during the class. They might be inaccurate or miss leading. I’ll post any correction or explanation in the form of comment to this blog entry.