如何在Python中获得对象在内存中占用的大小?


当前回答

这可能比看起来要复杂得多,这取决于你想要如何计数。例如,如果您有一个int类型的列表,您是否需要包含对int类型引用的列表的大小?(即-列表,而不是包含在其中的内容),或者你想包括实际指向的数据,在这种情况下,你需要处理重复引用,以及如何防止重复计数当两个对象包含对同一对象的引用时。

您可能想要查看python内存分析器之一,例如pysizer,以查看它们是否满足您的需求。

其他回答

下面是我根据之前对所有变量的列表大小的回答编写的一个快速脚本

for i in dir():
    print (i, sys.getsizeof(eval(i)) )

使用以下函数获取python对象的实际大小:

import sys
import gc

def actualsize(input_obj):
    memory_size = 0
    ids = set()
    objects = [input_obj]
    while objects:
        new = []
        for obj in objects:
            if id(obj) not in ids:
                ids.add(id(obj))
                memory_size += sys.getsizeof(obj)
                new.append(obj)
        objects = gc.get_referents(*new)
    return memory_size

actualsize([1, 2, [3, 4, 5, 1]])

参考:https://towardsdatascience.com/the-strange-size-of-python-objects-in-memory-ce87bdfbb97f

这可能不是最相关的答案,但我只对对象存储和检索感兴趣。因此将对象转储为pickle并检查pickle的大小就足够了

我用这个技巧…May在小对象上不准确,但我认为对于复杂对象(如pygame surface)比sys.getsizeof()更准确。

import pygame as pg
import os
import psutil
import time


process = psutil.Process(os.getpid())
pg.init()    
vocab = ['hello', 'me', 'you', 'she', 'he', 'they', 'we',
         'should', 'why?', 'necessarily', 'do', 'that']

font = pg.font.SysFont("monospace", 100, True)

dct = {}

newMem = process.memory_info().rss  # don't mind this line
Str = f'store ' + f'Nothing \tsurface use about '.expandtabs(15) + \
      f'0\t bytes'.expandtabs(9)  # don't mind this assignment too

usedMem = process.memory_info().rss

for word in vocab:
    dct[word] = font.render(word, True, pg.Color("#000000"))

    time.sleep(0.1)  # wait a moment

    # get total used memory of this script:
    newMem = process.memory_info().rss
    Str = f'store ' + f'{word}\tsurface use about '.expandtabs(15) + \
          f'{newMem - usedMem}\t bytes'.expandtabs(9)

    print(Str)
    usedMem = newMem

在我的windows 10, python 3.7.3,输出是:

store hello          surface use about 225280    bytes
store me             surface use about 61440     bytes
store you            surface use about 94208     bytes
store she            surface use about 81920     bytes
store he             surface use about 53248     bytes
store they           surface use about 114688    bytes
store we             surface use about 57344     bytes
store should         surface use about 172032    bytes
store why?           surface use about 110592    bytes
store necessarily    surface use about 311296    bytes
store do             surface use about 57344     bytes
store that           surface use about 110592    bytes

对于numpy数组,getsizeof不起作用-对我来说,它总是出于某种原因返回40:

from pylab import *
from sys import getsizeof
A = rand(10)
B = rand(10000)

然后(在ipython中):

In [64]: getsizeof(A)
Out[64]: 40

In [65]: getsizeof(B)
Out[65]: 40

不过令人高兴的是,:

In [66]: A.nbytes
Out[66]: 80

In [67]: B.nbytes
Out[67]: 80000