gc – control the garbage collector
This module provides an interface to the heap garbage collector: enabling or disabling automatic collection, forcing an immediate collection, querying the amount of allocated and free heap memory, and tuning the allocation threshold that triggers collection.
Functions
- gc.disable() None
Disable automatic garbage collection. Heap memory can still be allocated, and garbage collection can still be initiated manually using
gc.collect().
- gc.mem_alloc() int
Return the number of bytes of heap RAM that are allocated by Python code.
Difference to CPython
This function is MicroPython extension.
- gc.mem_free() int
Return the number of bytes of heap RAM that is available for Python code to allocate, or -1 if this amount is not known.
Difference to CPython
This function is MicroPython extension.
- gc.threshold(amount: int | None = None) int | None
Set or query the additional GC allocation threshold. Normally, a collection is triggered only when a new allocation cannot be satisfied, i.e. on an out-of-memory (OOM) condition. If this function is called, in addition to OOM, a collection will be triggered each time after amount bytes have been allocated (in total, since the previous time such an amount of bytes have been allocated). amount is usually specified as less than the full heap size, with the intention to trigger a collection earlier than when the heap becomes exhausted, and in the hope that an early collection will prevent excessive memory fragmentation. This is a heuristic measure, the effect of which will vary from application to application, as well as the optimal value of the amount parameter.
Calling the function without argument will return the current value of the threshold. A value of -1 means a disabled allocation threshold.
Difference to CPython
This function is a MicroPython extension. CPython has a similar function -
set_threshold(), but due to different GC implementations, its signature and semantics are different.