Awhile back, I mucked around with the "Cocoa Slides" demo from WWDC, which demonstrates the use of Core Animation. The last part of the demo, they layer in a Quartz Composer composition. I changed some things around to enable Garbage Collection. The combination of garbage collection + layers + Quartz Composer absolutely killed performance. I think it was a lot worse than 25%.
It also led to memory leaks and crashing, but I think they fixed those bugs at least. (I filed two bugs, one on the crash, the other on the performance. They mixed up the two and combined them into one and closed both when the crash was fixed. I had to force them to reopen the performance bug.)
by Eric Wing — Nov 06
It also led to memory leaks and crashing, but I think they fixed those bugs at least. (I filed two bugs, one on the crash, the other on the performance. They mixed up the two and combined them into one and closed both when the crash was fixed. I had to force them to reopen the performance bug.)