Python 3.8(2019年第一季度)将改变sys. js的一些结果。getsizeof, Raymond Hettinger在此宣布:

Python容器在64位版本上要小8个字节。

tuple ()  48 -> 40       
list  []  64 ->56
set()    224 -> 216
dict  {} 240 -> 232

这是在议题33597和稻田直树(甲烷)围绕紧凑型PyGC_Head和PR 7043的工作之后

这个想法将PyGC_Head大小减少到两个单词。 目前，PyGC_Head包含三个单词;Gc_prev, gc_next和gc_refcnt。 收集时使用Gc_refcnt，用于尝试删除。 Gc_prev用于跟踪和取消跟踪。 因此，如果我们可以在试删除时避免跟踪/取消跟踪，gc_prev和gc_refcnt可以共享相同的内存空间。

参见commit d5c875b:

从PyGC_Head中移除一个Py_ssize_t成员。 所有GC跟踪的对象(例如元组，列表，dict)大小减少4或8字节。

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

如果性能不是问题，最简单的解决方案是pickle和测量:

import pickle

data = ...
len(pickle.dumps(data))

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

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)) )

我自己也遇到过很多次这个问题，我写了一个小函数(受到@aaron-hall的回答的启发)和测试，它完成了我所期望的sys。Getsizeof to do:

https://github.com/bosswissam/pysize

如果你对背景故事感兴趣，这就是

编辑:附上下面的代码以方便参考。要查看最新的代码，请检查github链接。

    import sys

    def get_size(obj, seen=None):
        """Recursively finds size of objects"""
        size = sys.getsizeof(obj)
        if seen is None:
            seen = set()
        obj_id = id(obj)
        if obj_id in seen:
            return 0
        # Important mark as seen *before* entering recursion to gracefully handle
        # self-referential objects
        seen.add(obj_id)
        if isinstance(obj, dict):
            size += sum([get_size(v, seen) for v in obj.values()])
            size += sum([get_size(k, seen) for k in obj.keys()])
        elif hasattr(obj, '__dict__'):
            size += get_size(obj.__dict__, seen)
        elif hasattr(obj, '__iter__') and not isinstance(obj, (str, bytes, bytearray)):
            size += sum([get_size(i, seen) for i in obj])
        return size