CODEWITHSUNDEEP
python-2.7
wsdzbm
wsdzbm

Reputation: 3670

os.path.isfile faster than glob.glob?

I took a look at the source codes. glob.glob uses os.listdir and fnmatch to filter the file path. os.path.isfile tries to get file stat. However, I didn't find the source code for os.listdir and don't know how it's implemented.

When checking if a file exists, is os.path.isfile much faster than glob.glob since os.listdir takes time to list all of them?

Upvotes: 0

Views: 767

Answers (1)

faskiat
faskiat

Reputation: 689

glob.glob('./') essentially does what ls * would do on the command line. os.path.isfile needs a specific file handle in order to work, this means it will usually be faster than glob, simply because there will be less operations and glob does not return a boolean value. Here is a sample timed in my working directory

with glob:

In [2]: %timeit glob.glob('./')

The slowest run took 15.81 times longer than the fastest. This could mean that an intermediate result is being cached

100000 loops, best of 3: 9.8 μs per loop

with listdir:

In [5]: %timeit os.path.isfile('./')

The slowest run took 24.48 times longer than the fastest. This could mean that an intermediate result is being cached

100000 loops, best of 3: 4.04 μs per loop

Upvotes: 1

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