Memory occupied by basic type

• type

• # -*- coding: utf-8 -*- 
  # @Time     : 2019-12-19 11:16
  # @Author   : binger
  
  import sys
  
  a = None
  b = 1000.2311
  c = 1000
  d = True
  e = ""
  f = ()
  g = []
  h = set([])
  i = {}
  
  print(" %s size is %d " % (type(a), sys.getsizeof(a)))
  print(" %s size is %d " % (type(b), sys.getsizeof(b)))
  print(" %s size is %d " % (type(c), sys.getsizeof(c)))
  print(" %s size is %d " % (type(d), sys.getsizeof(d)))
  print(" %s size is %d " % (type(e), sys.getsizeof(e)), sys.getsizeof("12"))
  print(" %s size is %d " % (type(f), sys.getsizeof(f)), sys.getsizeof((1,)))
  print(" %s size is %d " % (type(g), sys.getsizeof(g)), sys.getsizeof([1, ]))
  print(" %s size is %d " % (type(h), sys.getsizeof(h)), sys.getsizeof(set([1, ])))
  print(" %s size is %d " % (type(i), sys.getsizeof(i)), sys.getsizeof({1: 1}))

• Result:
  Memory size ranking: none < float < int = bool < STR < tuple < list < set < Dict

•  <class 'NoneType'> size is 16 Byte 
   <class 'float'> size is 24 Byte
   <class 'int'> size is 28 Byte
   <class 'bool'> size is 28 Byte
   <class 'str'> size is 49  Byte 51
   <class 'tuple'> size is 56  Byte 64
   <class 'list'> size is 72  Byte 80
   <class 'set'> size is 232  Byte 232
   <class 'dict'> size is 248  Byte 248

   

Analysis:

• int and float:
  • Python 3 memory consumption in 64 bit systems of int and float: int > float
  • The overhead cost (pyobject · head) has doubled, but the size of the integer has changed from 32-bit to 64 bit, while the size of the floating-point number (double precision) is still 64:

  • 32 place
    int: cost = 10 bytes, value = 4 bytes
    float: cost = 8 bytes, value = 8 bytes
    
    64 place
    int: cost = 20 bytes, value = 8 bytes
    float: cost = 16 bytes, value = 8 bytes

• • Int and float are both 24B in 64 bit Python 2. But int does not contain long type (28B)

• Dictionary and linked list

from bintrees import bintree
import uuid, time, sys
import random


def create_uuid(msg):
    src_uuid = uuid.uuid4()
    name = "{}{}".format(time.time(), msg)
    return uuid.uuid3(src_uuid, name=name).hex


a = {create_uuid(i): random.randint(0, 10) for i in range(2000)}
b = {i: i for i in range(2000)}
ring = bintree.BinaryTree()
c = [ring.insert(create_uuid(i), i) for i in range(2000)]
ring2 = bintree.BinaryTree()
d = [ring2.insert(i, i) for i in range(2000)]

print("Dictionary 1", sys.getsizeof(a))
print("Dictionary 2", sys.getsizeof(b))
print("Two fork tree:", sys.getsizeof(c))
print("Two fork tree:", sys.getsizeof(d))

• • Result:

Dictionary 1 73832
Dictionary 2 73832
Binary tree: 16568
Binary tree: 16568