# Python Garbage Collection (gc)

Python uses automatic memory management. The primary mechanism is **reference counting**, but it also has a **garbage collector** (GC) to detect and collect reference cycles. The `gc` module provides an interface to this cyclic garbage collector.

## Reference Counting vs Garbage Collection

*   **Reference Counting**: Python's main memory management technique. Objects are deallocated immediately when their reference count drops to zero.
*   **Garbage Collection**: A background process that searches for and cleans up objects that reference each other (cyclic references) but are no longer reachable from the application.

## Importing the Module

```python
import gc
```

## Controlling the Garbage Collector

You can enable or disable the cyclic garbage collector.

```python
import gc

# Check if GC is enabled
print(gc.isenabled()) # Output: True

# Disable GC
gc.disable()

# Enable GC
gc.enable()
```

## Forcing Collection

You can trigger a manual garbage collection process using `gc.collect()`. This is useful in memory-constrained environments or for debugging.

```python
import gc

# Run a full collection
n = gc.collect()
print(f"Number of unreachable objects collected: {n}")
```

## Debugging Memory Leaks

The `gc` module allows you to inspect objects that the collector found to be unreachable but could not be freed.

```python
import gc

gc.set_debug(gc.DEBUG_LEAK)

# Force a collection to see what's leaking
gc.collect()
```

[[programming/python/python]]