How often does Python allocate?
21 days ago
- #Memory Allocation
- #Python
- #CPython Internals
- CPython represents each integer in a heap-allocated PyLongObject*.
- Python uses a freelist to reuse PyLongObject allocations, reducing the frequency of heap allocations.
- Small integers (-5 to 1025) are pre-allocated and shared to avoid repeated heap allocations.
- The print() function in Python allocates scratch PyLongObject* for conversions, even when avoidable.
- CPython's memory allocator uses pool allocation for objects, improving allocation speed and reducing fragmentation.
- Despite optimizations, Python's integer handling still involves significant overhead compared to direct CPU operations.
- Python lacks a tagged pointer optimization for integers, a common technique in other dynamic language interpreters.
- Zig's approach to memory allocation is highlighted as a contrast, where allocators are explicitly passed to functions.