因此,我试图将每个10MB的3个文本文件压缩到一个文件中作为tar.gz,但似乎并没有减少最终的tar.gz。最终的tar.gz文件大小仍然是30MB。为什么python tarfile gz没有减少文件大小
任何人都可以告诉我为什么会发生这种情况?我有压缩
>>> import os
>>> import sys
>>> import tarfile
>>> import tempfile
tarmode="w:gz"):
''>>> size_in_mb = 10
>>>
>>> def compress_str_to_tar(tmppath, files_str, tarfileprefix, tarmode="w:gz"):
... ''' compress string contents in files and tar. finally creates a tar file in tmppath
... @param tmppath: (str) pathdirectory where temp files to be compressed will be created
... @param files_str: (dict) {filename: filecontent_in_str} these will be compressed
... @param tarfileprefix: (str) output filename (without suffix) of tar
... @param tarmode: (str) w:gz or w:bz2
... '''
... tar = tarfile.open(os.path.join(tmppath, tarfileprefix+'.tar.'+tarmode.split(':')[1]), tarmode, compresslevel=9)
... for filename in files_str:
... with open(os.path.join(tmppath, filename), 'wb') as tmpf:
... tmpf.write(files_str[filename])
... tar.add(os.path.join(tmppath, filename), arcname=filename)
... tar.close()
...
...
>>> mail_size = 0
>>> files_str = {}
>>> for i in range(3):
... d = os.urandom(1*size_in_mb*(10**6))
... files_str['attachment'+str(i)+'.txt'] = d
... mail_size += sys.getsizeof(d)
...
...
/10**6)
tmppath = tempfile.mkdtemp()
print('tar-tmppath', tmppath)
tarfileprefix = 'tmpfoobar'
compress_str_to_tar(tmppath, files_str, tarfileprefix, 'w:gz')
print('mail_size', float(sys.getsizeof(open(os.path.join(tmppath, tarfileprefix+'.tar.gz')).read()))/10**6)
>>> print('mail_size', float(mail_size)/10**6)
('mail_size', 30.000111)
>>>
>>> tmppath = tempfile.mkdtemp()
>>> print('tar-tmppath', tmppath)
('tar-tmppath', '/tmp/tmpndifyt')
>>> tarfileprefix = 'tmpfoobar'
>>> compress_str_to_tar(tmppath, files_str, tarfileprefix, 'w:gz')
>>> print('mail_size', float(sys.getsizeof(open(os.path.join(tmppath, tarfileprefix+'.tar.gz')).read()))/10**6)
('mail_size', 30.009782)
>>>
>>>
>>>
代码需要一些格式化。 –
不是所有的东西都可以压缩,或者只要压缩一遍又一遍就可以将任何东西压缩到非常小的尺寸。你压缩什么样的文件?如果使用不同的方法创建'.tar.gz',会发生什么? –
我会同意不是所有的东西都压缩下来,但他说的是_text_文件。我不希望二进制文件具有良好的压缩比,但文本应该比_no_压缩更好。 –