Garbage Collector Differences between Java and CSharp

More on our old friend, the Garbage Collector- also known on the streets as the 'GC'.

Common Default Behavior

At indeterminate times, the GC comes around, finds and frees up

every unreferenced object- these are objects that cannot be traced to a long living root object
every object referenced only by a WeakReference
and- for Java only- if free memory is low, every object referenced only by a SoftReference

C# does not have SoftReferences. Why this is so? Two leading theories on StackOverflow say

Java has four levels of reference strength- (strong, soft, weak, and phantom)- and that's way too confusing. C# just keeps it simple at two- strong and weak. Nice.
On 32-bit Windows platforms, C#, unlike Java, uses an entire process' addressable memory space- 4GB. It's 2GB in practical terms because the OS/kernal claims usage on the other 2GB, but it's also possible to push the user space limits to 3GB using boot flags. With more memory at is disposal, C# apps are less likely than Java apps to struggle for memory- which is how SoftReferences are likely to be used.With Java on Linux, the way to find the maxium heap size is via:

java -XX:+PrintFlagsFinal -version | grep i maxheapsize

In C#, it is not uncommon to see code explicitly requesting a garbage collection. The GC collects immediately at the point in the code.

In Java however, the GC collection call is only a request. The GC alays collects at an indeterminate time in the future.