A couple of days ago, I posted a message regarding extremely high CPU usage in an application I was building. Eventually, I concluded that the problem was not the Flex app, but some other processes on the same machine.
However, I have since found out that I was incorrect -- the problem was the Flex app after all. So for anyone who read the original post and wondered what might be happening -- in particular, Rick Fotis, who attempted to help -- here's what was going on: The issue was caused by the combination of a creationPolicy setting and the use of a set of skins called iCandy, from the ScaleNine site. Now -- I'm not criticizing the developer of the skins. I don't know enough about what really went on. But I do know this: I had set the creationPolicy on a TabNavigator to "all." When I removed this, the CPU usage dropped markedly. But when I went into one of the tabs, the usage picked back up, although not as much. I removed the reference to the skin stylesheet. The CPU usage did what it was supposed to do: spike occasionally, then drop to nothing. So I can only conclude that the skins were causing continual redraws in the background. I've found some blog posts from the folks at EffectiveUI discussing performance problems with stateful skins, so I'm not the only one who's encountered it. Here's one of the posts: http://patrickhansen.com/blog/index.php/2009/03/05/flex-stateful-skins-vs-stateless . Moral is: be careful of stateless skins, even though they seem to be recommended by Adobe. The use of a large number of skinned components (checkboxes, text inputs, etc.) can evidently be a problem -- and I didn't even have that many. I don't know enough to make a technical analysis of the issue; but I hope this may save someone else a few hours (or in my case, days) of pain. -- Thanks, Tom Tom McNeer MediumCool http://www.mediumcool.com 1735 Johnson Road NE Atlanta, GA 30306 404.589.0560
