Saturday, October 29, 2011

ITDevCon 2011–recap

ITDevCon 2011 has closed its doors and I’m back at home, completely washed out. It was tiresome but it was also fun!

All the sessions I’ve visited were interesting and I always managed to learn something new. If I would have to expose three most important products I didn’t knew before, I would mention (in the order I learned about them) CopyCat, a great database replication engine which you can compile into your application; Delphi Relax, an extension to Delphi’s WebBroker and DataSnap REST architecture; and DORM, a new ORM for Delphi.

Thursday, October 27, 2011

ITDevCon 2011

Just few photos from the opening session …


Wednesday, October 26, 2011

Nasty COM regression in XE2

David Heffernan found a nasty RTL bug in XE2 COM implementation.

Is COM broken in XE2, and how might I work around it?

I’ve found a workaround (see the link above), but it is ugly and this should really be fixed in the next XE2 update so please – vote on the QC #100414!

Update: XE2 Update 2 fixes the bug described above. Great response time from Embarcadero!

Saturday, October 22, 2011

Multithreading Made Simple–additional material

Thank you for listening to my CodeRage 6 presentation! I’m very sorry that there were some issues with the sound that were caused by network problems :( If you want to look at the presentation again (or for the first time), please go to the Embarcadero CodeCentral or download the presentation from my Dropbox.

To help you understanding the complicated world of multithreading I’ve repacked the complete presentation in a longish PDF with slides and a transcript of my talk. (Actually, it was done vice versa – first I wrote that script and only then I prepared the presentation based on the script.) You can also download the code that was used for the presentation.

If you have any questions or if you asked me something after the presentation and I didn’t understand your question and answered something completely unrelated or even if my answer was too short and you want to learn more - feel free to leave a comment here or open a new topic in the forum.

Friday, October 21, 2011

Multithreading Made Simple

Keep in mind – my session on high-level OmniThreadLibrary stuff goes on air at 06:00 AM PDT / 15:00 CET.

Thursday, October 20, 2011

OmniThreadLibrary in Practice [1]–Web Download and Database Storage

From time to time I get a question on the OmniThreadLibrary forum that could be of interest to other OmniThreadLibrary users. As I believe that many of you don’t follow that forum I have decided to repost such questions on the blog (and provide answers, of course).

The first question in this series was asked by GoustiFruit:

I need to download a list of web pages, extract data on them and then store these data in a SQLite database. The downloading/extracting part will happen in multiple threads (I'm using Synapse), but querying the database needs to be done asynchronously as I can only have one concurrent access to it.
So I'd like to know how (conceptually) I could implement that ? My first idea is to run one single thread for querying the DB, run several threads for each Url to download/analyse and then exchange messages between these threads and the querying thread, with the extracted data as a parameter: does it make sense or am I totally wrong? I also read things about the connection pool concept but I'm not sure if it applies when only one connection is allowed at one time?

Sunday, October 16, 2011

CodeRage 6 is Starting!

Tomorrow starts the CodeRage week!

My presentation is scheduled for Friday, 21st, at 06:00 PDT / 15:00 CET, which is early for the West coast folks but great for East cost and us Europeans. See you there!

Tuesday, October 11, 2011

OmniThreadLibrary 2.2

Only three months since 2.1 and a new release is already here? What’s going on?

I had to change some things to make OTL work in XE2 and although I could simply release new files as a patch I noticed that I’ve also done quite some work on exception handling and that I could equally well wrap everything in a new release.

Here it is: ZIP, SVN, UML diagrams (provided by Rich Shealer; Rich, thanks!).

Friday, October 07, 2011

Hear Me at CodeRage

CodeRage 6 will start in ten days! Will you be there? I’ll be joining it for the sixth time as a listener and for the first time as presenter!
The exact date and time of the presentation was not determined yet (if you look at the session list you’ll see some empty spots – I’m one of them). I’ll let you know when the timeslot is fixed. In the meantime, go and register for the conference!
The topic of my talk you can probably guess – multithreading with the OmniThreadLibrary. Due to a limited session time and to attract as wide an audience as possible, I’ve decided to focus on high-level OTL functionality. The title of the talk is Multithreading made simple and it will deal with Async, Future, ForEach, Pipeline, ForkJoin, Join, and ParallelTask.