11-07-2012 03:59 AM
This symbol indicates that the garbage collector is running.
If you see it a lot when running your app, then you are perhaps using too many or too large Objects. The best thing to so is review your code looking for Objects you get and immediately 'free' or some processing you do a lot that uses temporary Objects, like String manipulation.
Use the Object profiler to find this out. Sorry I can't point you directly at anything that will tell you how to do it, but search on here because I think the use of the profiler has been discussed on at least one thread here.