Quote:Original post by Vexorian
The question was: Why the lack of an "auto destroy object when nothing is referencing to it" system?

Because the garbage collector knows what its doing. The whole idea is that you don't worry about garbage collection in general, you just get things working. By adding a second type of garbage collection, you greatly increase the complexity of the programs, which removes the entire reason for it to exist in the first place.

Also, keep in mind that deallocation isn't free. Whenever possible, you want to deallocate lots of memory all at once, it stands to make later allocations cheaper.

CM

Well, I guess it is possible to implement a reference counting & releasing object by using unsafe code...

But I am sure you are better of with assuming the GC is smarter than you ;)

A couple more comments, and I'm sure you're not going to like this :)

From my understanding one way to write games under .Net is to avoid having the garbage collector coming up at all. Tricks involve keeping things in the stack by using unboxed structures rather than reference types, and reusing allocated reference elements rather than allocating new ones.

I remember a while ago in VB 2002 that I was scratching my head trying to figure out why didn't the garbage collector clean up an object from which I had removed all references to from my code and then called gc.collect (with different generation levels, and several times)

It turned out that an optimization had created a copy of the variable that had originally pointed to the object, and that copy was just being allowed to fall out of scope and stack at the end of the method, but obviously I had code in the same method waiting for the destruction of the object :).

Basically, this is hard to accept, and kind of a philosophical step, but it seems to be easier to accept garbage collection as not being predictable, and code accordingly, expecting either slowdowns (which can be acceptable in non real time games, such as board games), or avoiding it at all.

who has seen actual freezes in a game when the garbage collector runs?

i have not, and the gc runs quite often in my game due to lazy coding.