PYTHON100% Active LaboratoryLAB

CPython Dynamic Array Over-Allocation & Amortization Lab

Inspect CPython list resizing formula (allocated = size + (size >> 3) + 6) during progressive `append()` calls, showing exact capacity jumps.

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PYTHON • VISUALIZATIONPython Memory Model & PyObject Pointer Laboratory

PYTHON • MEMORY INTERNALSPyObject & Reference Semantics

Python Object Identity (`is`), Equality (`==`) & PyObject Pointer Laboratory

Variable `a` value:

Variable `b` value:

Call Stack Frame (Names / Pointers)

Variable a→ Pointer: 0x7f1a000

Variable b→ Pointer: 0x7f1a000

CPython Heap (PyObject Headers)

Address: 0x7f1a000refcnt: 2

PyLongObject: 100

Equality (`a == b`)

True

Compares values

Identity (`a is b`)

True

Compares memory addresses `id(a) == id(b)`

Python CPython Architecture Insight:

Python pre-allocates an internal array of integer objects for values between -5 and 256 at interpreter startup. When you assign any integer in this range, Python points to the cached singleton PyObject rather than allocating a new object on heap!

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