How many bytes per element are there in a Python list (tuple)?

Question

For example, how much memory is required to store a list of one million (32-bit) integers?

alist = range(1000000) # or list(range(1000000)) in Python 3.0
         


        

Answer 1

A new function, getsizeof(), takes a Python object and returns the amount of memory used by the object, measured in bytes. Built-in objects return correct results; third-party extensions may not, but can define a __sizeof__() method to return the object’s size.

kveretennicov@nosignal:~/py/r26rc2$ ./python
Python 2.6rc2 (r26rc2:66712, Sep  2 2008, 13:11:55) 
[GCC 4.2.3 (Ubuntu 4.2.3-2ubuntu7)] on linux2
>>> import sys
>>> sys.getsizeof(range(1000000))
4000032
>>> sys.getsizeof(tuple(range(1000000)))
4000024

Obviously returned numbers don't include memory consumed by contained objects (sys.getsizeof(1) == 12).