On Feb 9, 2008 1:30 AM, Adriaan de Groot <groot at kde.org> wrote: > On Friday 08 February 2008 19:47, Manish Chakravarty wrote: > > As a starting point, I want to do dynamic tracing of this application. > > Though this app is relatively small, it demonstrates the power of Qt's > meta > > object system and powerful object introspection capabilities. > > I don't see the connection here between dtrace and the Qt meta-object > system. > I mean, this is a fun demo app, but what makes it special as a beginning > for > dtrace? Since I'm not very creative regarding what dtrace probes are > possible, I may be missing something obvious here.
As a starting point, I want to be able to probe what is going on behind the scenes when meta object calls are made ( and how efficient they are, getting an idea of their time complexity, etc ) Let's say you there is a KDE4 or Qt4 app whose UI has been designed using the Qt Designer. The XML .ui file is being read at run time to draw widgets and make signal-slot connections I know from experience that is not as efficient as drawing the UI by hand. But how do i quantify it? I attach a probe to the QObjects that are being instantiated at run-time. I would have an idea! Another example: I have heard that Qt is leaking memory on Solaris ( at least the way Qt is being built by the KDE/Solaris project) Where exactly is it leaking memory and why? QObject has (rudimentary) garbage collection. Why is gc not happening properly? DTrace would provide answers. In fact http://developers.sun.com/solaris/articles/dtrace_cc.html demonstrates how to catch memory leak problems in C++ apps. We need to make it more Qt-specific ( by writing probes to the classes i mentioned in my original mail ) to get a better idea, And last but not the least, the ability to dynamically trace Qt apps will help a lot of Qt/KDE developers write much better apps on the Solaris ( and even OSX ) platform ( not sure if FreeBSD has Dtrace ) How does this idea sound? -- Manish monzie on #kde-solaris > > > [ade] > _______________________________________________ > kde-discuss mailing list > kde-discuss at opensolaris.org > http://mail.opensolaris.org/mailman/listinfo/kde-discuss > -- Manish Chakravarty http://manish-chaks.livejournal.com/ -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://mail.opensolaris.org/pipermail/kde-discuss/attachments/20080209/3027e0e7/attachment.html>
