Thiago Macieira wrote: Oops, missed this one.
> Unfortunately, we can't change anymore. Can someone explain what could possibly be broken by changing this? Can the current base-level QObject::timerEvent() be used for anything constructive other than heating the office or preventing a CPU core from going to sleep? I only made my suggestion because it seemed rather evident that anyone using the QObject timer would override the timerEvent() method. That said, it does seem a bit overkill to give each and every instance inheriting QObject timer features. Most will presumably never use that in a typical application, would they? >> It took me an unreasonable amount of time trying to figure out the reason >> for the burning, the fact that QCocoaMenu::timerEvent() could be being >> called as fast as possible and for nothing occurred to me only after trying >> all other possibilities. And I knew only the timer change could be the >> culprit; I can only imagine how much more time I'd have spent if this bug >> had been latent for a few months. > > i'm glad you found it. > > How did you? How did I discover the issue? I have a top-of-the-2011-line laptop i7 in a 13" MBP, and no airco. One tends to notice when it gets busy and remains busy when you're not expecting it, and you know something's wrong when a quick look in `top` shows nearly 100% CPU for an application that appears to be doing nothing (KDevelop in this case, and fortunately I discovered afterwards that Assistant worked as a demonstrator too). Found the bug/fix? The usual way, reverting all changes and restoring them in order of least likely culprit. Then by generating trace output, evidently I thought last of putting it *before* the timer ID check, and then I had to consult the docs to confirm that one indeed needs to kill the timer when done. I'd never have guessed that a noop event handler callback could have pump this many resources. > Actually, there is an overhead, albeit very small one: the timer ID is stored. Indeed, I wondered about that, and then let it pass because the compiler will probably optimise it away. R. _______________________________________________ Development mailing list Development@qt-project.org http://lists.qt-project.org/mailman/listinfo/development
