Garbage Collection

Introduction to Garbage Collection

Garbage collection (GC) is an automatic memory management process in .NET that manages the allocation and release of memory for objects.

How Garbage Collection Works

The .NET Garbage Collector periodically scans memory for objects that are no longer referenced (i.e., not reachable by the application) and reclaims their memory.

// Example of object creation and usage
public class MyClass {
    public void DoSomething() {
        // Allocate memory for an object
        SomeClass obj = new SomeClass();
        
        // Use the object
        obj.DoWork();
        
        // Once 'obj' is no longer referenced, GC can reclaim its memory
    }
}
    

Generations in Garbage Collection

.NET uses a generational garbage collection model with three generations (0, 1, 2). New objects start in Generation 0 and are promoted to higher generations based on their longevity.

// Objects in Generation 0
SomeClass obj1 = new SomeClass();

// Long-lived objects promoted to Generation 1 and 2
SomeClass obj2 = new SomeClass();
    

Forcing Garbage Collection

While .NET's GC is automatic, you can manually trigger garbage collection using GC.Collect() and GC.WaitForPendingFinalizers() methods.

// Force garbage collection
GC.Collect();
GC.WaitForPendingFinalizers();
    

Memory Performance Considerations

Optimize memory usage by minimizing object allocations, managing object lifetimes, and understanding GC behavior for better application performance.

Conclusion

Garbage collection in .NET automates memory management, ensuring efficient use of resources and reducing the risk of memory-related errors, while developers focus on application logic.