Python-如何显示所有变量的大小

Question

Python-如何显示所有变量的大小

82

我想同时打印出我的作用域中所有变量的内存大小。

类似于这样：

for obj in locals().values():
    print sys.getsizeof(obj)

但是在每个值之前添加变量名称，以便我可以看到需要删除或分批拆分哪些变量。有什么想法？

- user278016

3个回答

73

使用 .items() 可以同时迭代字典的键和值。

from __future__ import print_function  # for Python2
import sys

local_vars = list(locals().items())
for var, obj in local_vars:
    print(var, sys.getsizeof(obj))

- zsquare

3

这导致了 RuntimeError: 在迭代过程中字典大小发生了变化。 - Pradeep Singh

使用 local_vars = list(locals().items()) 可以避免 RuntimeError。 - TomDLT

7

如果有人想知道尺寸的单位是什么：它是 **字节(Bytes)**。sys.getsizeof()。 - xanjay

0

我发现对于某些容器，我没有得到正确的答案（仅限开销？）。
将@jan_Glx上面的答案与下面帖子中的片段结合起来
如何知道Python对象（如数组和字典）的字节大小？-简单方法

from __future__ import print_function
from sys import getsizeof, stderr, getsizeof
from itertools import chain
from collections import deque
try:
    from reprlib import repr
except ImportError:
    pass

def sizeof_fmt(num, suffix='B'):
    ''' by Fred Cirera,  https://dev59.com/unNA5IYBdhLWcg3wF5uO#1094933, modified'''
    for unit in ['','Ki','Mi','Gi','Ti','Pi','Ei','Zi']:
        if abs(num) < 1024.0:
            return "%3.1f %s%s" % (num, unit, suffix)
        num /= 1024.0
    return "%.1f %s%s" % (num, 'Yi', suffix)

def total_size(o, handlers={}, verbose=False):
    """ Returns the approximate memory footprint an object and all of its contents.

    Automatically finds the contents of the following builtin containers and
    their subclasses:  tuple, list, deque, dict, set and frozenset.
    To search other containers, add handlers to iterate over their contents:

        handlers = {SomeContainerClass: iter,
                    OtherContainerClass: OtherContainerClass.get_elements}

    """
    dict_handler = lambda d: chain.from_iterable(d.items())
    all_handlers = {tuple: iter,
                    list: iter,
                    deque: iter,
                    dict: dict_handler,
                    set: iter,
                    frozenset: iter,
                   }
    all_handlers.update(handlers)     # user handlers take precedence
    seen = set()                      # track which object id's have already been seen
    default_size = getsizeof(0)       # estimate sizeof object without __sizeof__

    def sizeof(o):
        if id(o) in seen:       # do not double count the same object
            return 0
        seen.add(id(o))
        s = getsizeof(o, default_size)

        if verbose:
            print(s, type(o), repr(o), file=stderr)

        for typ, handler in all_handlers.items():
            if isinstance(o, typ):
                s += sum(map(sizeof, handler(o)))
                break
        return s

    return sizeof(o)


##### Example call #####

for name, size in sorted(((name, total_size(value, verbose=False)) for name, value in list(
                          locals().items())), key= lambda x: -x[1])[:20]:
    print("{:>30}: {:>8}".format(name, sizeof_fmt(size)))

- Dara O h

网页内容由stack overflow 提供, 点击上面的

可以查看英文原文，
原文链接

- jan-glx · Accepted Answer

再多写一点代码，但适用于Python 3，并提供了一个排序的、易读的输出：

import sys
def sizeof_fmt(num, suffix='B'):
    ''' by Fred Cirera,  https://dev59.com/unNA5IYBdhLWcg3wF5uO#1094933, modified'''
    for unit in ['','Ki','Mi','Gi','Ti','Pi','Ei','Zi']:
        if abs(num) < 1024.0:
            return "%3.1f %s%s" % (num, unit, suffix)
        num /= 1024.0
    return "%.1f %s%s" % (num, 'Yi', suffix)

for name, size in sorted(((name, sys.getsizeof(value)) for name, value in list(
                          locals().items())), key= lambda x: -x[1])[:10]:
    print("{:>30}: {:>8}".format(name, sizeof_fmt(size)))

示例输出:

                  umis:   3.6 GiB
       barcodes_sorted:   3.6 GiB
          barcodes_idx:   3.6 GiB
              barcodes:   3.6 GiB
                  cbcs:   3.6 GiB
         reads_per_umi:   1.3 GiB
          umis_per_cbc:  59.1 MiB
         reads_per_cbc:  59.1 MiB
                   _40:  12.1 KiB
                     _:   1.6 KiB

请注意，此操作仅会打印出前10个最大的变量，并且对于其余的变量将保持沉默。如果你真的想要打印全部变量，请从倒数第二行移除[:10]。