Explain how the garbage collection mechanism in C# is being handled?

Question

Explain how the garbage collection mechanism in C# handles cyclic references. What impact do weak references and the IDisposable pattern have in such a scenario, and how could you use both to mitigate potential memory leaks caused by cyclic dependencies? Provide code examples to illustrate your explanation.

Context to Consider:

Describe the different generations used by the .NET Garbage Collector (Gen 0, Gen 1, Gen 2).
Explain how the garbage collector deals with cyclic references, particularly in regard to object graphs.
Discuss the use of weak references to manage memory and provide an example where weak references prevent retention of unnecessary objects.
Explain the role of the IDisposable interface, how deterministic disposal works, and how to integrate it with garbage collection to deal with cyclic dependencies.

Madhu Patel · Answer

Garbage Collection in C# and Cyclic References The .NET Garbage Collector (GC) handles cyclic references using an object graph approach. It tracks object references, identifying if an object can still be reached from the roots (e.g., static fields, local variables). If a set of objects reference each other but are not reachable from the roots, the GC will collect them even if they form a cycle. .NET Garbage Collector Generations The GC divides objects into three generations: Gen 0 : Newly allocated objects. The GC collects here frequently. Gen 1 : Objects surviving Gen 0 collections. Less frequent collections. Gen 2 : Long-lived objects (e.g., static data). Rarely collected. Objects move to the next generation if they survive a collection cycle. Handling Cyclic References Cyclic references themselves do not prevent garbage collection . The GC can detect that a group of objects (even if they reference each other) is unreachable from the roots and will collect them.