Python3 基本類型在64位上的佔用內存狀況

基本類型佔用的內存

• 類型

• # -*- 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}))

• 結果：
  內存大小排行： 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

   

分析：

• int和float:
  • int和float的64位系統中的 Python 3 內存消耗：int > float
  • 間接費用（PyObject_HEAD）增長了一倍，但整數的大小從32位變爲64位，而浮點數（雙精度）的大小仍爲64：

  • 32位
    int：開銷= 10字節，值= 4字節
    float：開銷= 8字節，value = 8字節
    
    64位
    int：開銷= 20字節，值= 8字節
    float：開銷= 16個字節，值= 8個字節

• • 在64位 Python 2 中 int 和 float 均爲 24B。可是 int 不包含 long類型（28B）

• 字典與鏈表

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("字典1", sys.getsizeof(a))
print("字典2", sys.getsizeof(b))
print("二叉樹：", sys.getsizeof(c))
print("二叉樹：", sys.getsizeof(d))

• • 結果：

字典1 73832
字典2 73832
二叉樹： 16568
二叉樹： 16568