python: class vs tuple huge memory overhead (?)

Question

I\'m storing a lot of complex data in tuples/lists, but would prefer to use small wrapper classes to make the data structures easier to understand, e.g.

class Pe         


        

Answer 1

There is yet another way to reduce the amount of memory occupied by objects by turning off support for cyclic garbage collection in addition to turning off __dict__ and __weakref__. It is implemented in the library recordclass:

$ pip install recordclass

>>> import sys
>>> from recordclass import dataobject, make_dataclass

Create the class:

class Person(dataobject):
   first:str
   last:str

or

>>> Person = make_dataclass('Person', 'first last')

As result:

>>> print(sys.getsizeof(Person(100,100)))
32

For __slot__ based class we have:

class Person:
    __slots__ = ['first', 'last']
    def __init__(self, first, last):
        self.first = first
        self.last = last

>>> print(sys.getsizeof(Person(100,100)))
64

As a result more saving of memory is possible.

For dataobject-based:

l = [Person(i, i) for i in range(10000000)]
memory size: 681 Mb

For __slots__-based:

  l = [Person(i, i) for i in range(10000000)]
  memory size: 921 Mb