At the time of this writing, Go 1.2.2's compiler utilizes a naive mark/sweep garbage collector, which assigns a reference rank to objects and clears them when they are no longer in use. This is noteworthy only to point out that it is widely considered a relatively poor garbage collection system.
So why does Go use it? As Go has evolved; language features and compiler speed have largely taken precedence over garbage collection. While it's a long-term development timeline for Go, for the time being, this is where we are. The tradeoff is a good one, though: as you well know by now, compiling Go code is light years faster than, say, compiling C or C++ code. Good enough for now is a fair description for the GC. But there are some things you can do to augment and experiment within the garbage collection system.
To get an idea of how the garbage collector is managing the stack at any time, take a look at the runtime.MemProfileRecord object, which keeps track of presently living objects in the active stack trace.
You can call the profile record when necessary and then utilize it against the following methods to get a few interesting pieces of data:
You can place the following code in a heavy loop in your application to get a peek at all of these:
var mem runtime.MemProfileRecord
obj := mem.InUseObjects();
bytes := mem.InUseBytes();
stack := mem.Stack();
fmt.Println(i,obj,bytes)