Guitar Hero III Mobile is now available for BlackBerry. Go to http://www.bplay.com/promo/guitarhero and you can get a trial version there. The price for the full version is 14.99 $ and it includes 15 tracks. New tracks will be available for download soon.
As I stated out earlier I am a huge Guitar Hero III fan so I have to give this version a try - stay tuned for updates.
Last week Truecrypt version 5.1 was released. I downloaded and installed it today. Everything works fine so far, my encrypted volumes still work 
The performance improvements they made are not recognizable for me because Truecrypt already worked smooth and fast with the 4.x versions for me.
Lately we experienced a lot of performance problems in our AJAX applications. Since we went online a year ago we always had problems with users of Internet Explorer 6 but within the last three months they got more and more.
We already knew that this had something to do with the huge memory amount the Internet Explorer 6 uses after some hours of working with our application. I used the Process Explorer to analyze which page causes the problem. After identifying the page I did some reloads of it and generated the following image:
As you can see, with every reload the memory amount consumed by the Internet Explorer 6 increased (for about 2 megabytes). This memory amount was never released, even if a complete different page of the application was loaded. The only way to release the memory again was to close the instance of the browser.
I did a web search and found this interesting link about “Understanding and Solving Internet Explorer Leak Patterns”. It describes four different situations that could lead to memory leaks in Internet Explorer by using good graphics and example code.
I was really shocked when I realized that the Internet Explorer 6 holds those elements in memory even after the user left the page and loaded another one. In other browser it is just important to make sure that inside the page the references to elements are released proper when working with a lot of AJAX code without reloading the page.
We are using prototype and scriptaculous as JavaScript libraries. Another library used to display a clickable calendar for date input fields is the JSCalendar from dynarch.com. To find out which elements of the DOM and which script code cause the memory leak I searched for another tool – and found sIEve.
With sIEve it was easy to detect to suspicious elements. After reloading the page inside of sIEve a lot of possible leaks were detected and the list looked like this:
By looking through the code of the page I found out that all the elements in the list had events registered (onclick, onkeyup, onchange, …) and the assigned methods contained closures (see this link for details again).
Some were caused by the used calendar library. I already sent an email to the author Mihai Bazon. He wrote a very good article about the problem and I could not believe that there is exactly that bug inside his library. Maybe we are using it incorrect.
The other leaks were caused by prototype. Although prototype has a built in mechanism that should unlink registered events when the page is unloaded they survived the reload. I found out that there is a bug in the 1.6.0 version of prototype. The mechanism was changed between version 1.5 and 1.6. This explained why the problem got bigger after updating out application to the new prototype version.
To fix the problem I registered a method to the unload event of the page that removes all the critical registered events. This looks like:
1 2 3 4 5 6 7 8 | function breakLeaks() { $('img_calendar').onclick = null; Event.stopObserving("fieldX", "keyup", keycheck, false); Event.stopObserving("fieldX", "click", mousecheck, false); ... } Event.stopObserving("window", "unload", breakLeaks, false); |
After changing the page like that I tested it again with sIEve and no more leaks were detectd. Then I used the Process Explorer again to monitor the memory consumption of the Internet Explorer. The graph now looked like:
The memory footprint is a lot smaller now and memory allocated by the reload was completely released again.
Microsoft now provides all of its Internet Explorer versions in separate downloadable virtual PC images. This is extremely useful for web developers because it allows them to test their applications for compatibility.
If you have got some time left (about an hour or so) I would recommend you to watch the interview Guy Kawasaki made with Steve Ballmer at Mix 08 this week. It is the best interview of Steve Ballmer I have ever seen. Although he said of PR sentences it shows a lot personality. It is really funny to see him talk about his competitors Google and Apple. He is truly enthusiastic about what he and his company does. The monkey dance for web developers is another highlight
PS: I decided to leave the embedded movie although it is based on MS Silverlight …
Today I found this post on problogger.net that made me aware of another Google tool I did not use until now that could be very helpful. I am talking about Google Webmasters Tools. Google Webmasters Tools allow you to see a website from the view of the Google crawlers. This means it is possible to check a lot of statistics like the top queries in specific months or to see what words went into the Google search index.
Another very interesting feature is to list all the external links to the specific page of your site and in total. This tells me I definitely have to get more links pointing to my blog
This tools is a nice addition to the other Google tools I use to manage my blog, which are Analytics, Alerts, AdSense and AdWords.
I am running my own mail server now for over five years. There are a lot of good free email services out there but I am not satisfied with their spam filters. I am getting about 300 spam mails a day and with my current solution only one of them makes it into my inbox per month.
The second reason is that I do not want to delete or archive my mails to often and I want to have access to them anywhere at any time. Therefor I need an IMAP server with a lot of storage. Most free mail services provide this nowadays but did not five years ago. I thought about using GMAIL lately but I am not completely happy with storing all my mails on Google servers.
First I used an old PC that ran in my home office day and night. My home internet connection always had a high enough upload bandwidth to allow that. The mail server was no dedicated mail server for my domain. I used fetchmail to receive my emails from multiple POP3 servers.
About six months ago I configured a VPS machine to act as the dedicated mail server for my domains. I host multiple mail accounts for my family and friends on it. This post explains what I did to configure my perfect personal mail server.
Read the rest of this entry »
Nearly a year ago I stumbled upon a post on lifehacker about Launchy. I downloaded, installed and used the tool - and I had to blog about it.
Now for everybody who does not know it until know: I love Launchy! It is THE tool that improved my whole using-a-PC-experience to most in the last year (next to using Google Reader).
Launchy creates an search index of all the shortcuts on your PC so you can start any application by pressing ALT+Space and entering a part of its name. It is also possible to open web bookmarks and do calculations. You may even extend its functionality with plugins.
It increases the speed of working with Windows a lot because you do not have to get your hands of the keyboard just to open an application.
Maybe you have noticed my new booklist widget in the right sidebar. In the last years it occurred very often that somebody asked me if I know a good book on a certain topic. I recommended books to my colleagues, students and friends.
Some weeks ago I thought that it would be easier to have place where I list my favorite books so I could point to the list if somebody asks me. Now this is what I have done with the booklist.
I read all of the books in the list by myself and I really recommend them. Of course every book deals with a special topic but mostly the are related to software development.
In the future I want to do more detailed summaries and recommendations of books I just read.
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I am going to visit the 
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