I am running an application that creates and forgets large amounts of objects, the amount of long existing objects does grow slowly, but this is very little compared to shor
You can try reducing the new size. This will case it to make more, smaller collections. However it can cause these short lived objects to be passed into tenured space. On the other hand you can try increasing the NewSize which means less objects will pass out of the young generation.
My preference however is to create less garbage and the GC will behave in a more consistent manner. Instead of creating objects freely, try re-using them or recycling objects. You have to be careful this this doesn't cause more trouble than its worth, but you can reduce the amount of garbage created significantly in some applications. I suggest using a memory profiler e.g. YourKit to help you identify the biggest hitters.
An extreme case is to create so little garbage it doesn't collect all day (even minor collections). It possible for a server side application (but may not be possible for a GUI application)