bytesio_test.py

import io, cStringIO, StringIO
import time
import functools
from memory_profiler import memory_usage

def data_gen():
    return 'datadata' * 100

times = 1000000
dflt_interval = 0.5


def print_timing(func):
    @functools.wraps(func)
    def wrapper(*args, **kwargs):
        t1 = time.time()
        res = func(*args, **kwargs)
        t2 = time.time()
        print '{} took {:0.3f} ms'.format(func.func_name, (t2-t1)*1000.0)
        return res
    return wrapper

def test_wrapper(number):
    def actual_decorator(func):
        @functools.wraps(func)
        def returned_func(*args, **kwargs):
            for i in range(number):
                func(*args, **kwargs)
        return returned_func
    return actual_decorator


@print_timing
@test_wrapper(times)
def test_cStringIO():
    s = cStringIO.StringIO(data_gen())
    s.read()
    s = cStringIO.StringIO()
    s.write(data_gen())
    s.seek(0)


@print_timing
@test_wrapper(times)
def test_io_BytesIO():
    s = io.BytesIO(data_gen())
    s.read()
    s = io.BytesIO()
    s.write(data_gen())
    s.seek(0)


@print_timing
@test_wrapper(times)
def test_StringIO():
    s = StringIO.StringIO(data_gen())
    s.read()
    s = StringIO.StringIO()
    s.write(data_gen())
    s.seek(0)


print memory_usage((test_cStringIO, (), {}), interval=dflt_interval)
print memory_usage((test_io_BytesIO, (), {}), interval=dflt_interval)
print memory_usage((test_StringIO, (), {}), interval=dflt_interval)

result

➜  python bytesio_test.py
test_cStringIO took 2297.567 ms
[9.3046875, 9.5078125, 40.39453125, 40.39453125, 40.39453125, 40.39453125, 32.76171875]
test_io_BytesIO took 2722.704 ms
[32.796875, 32.96875, 40.42578125, 40.42578125, 40.42578125, 40.42578125, 40.42578125, 40.42578125]
test_StringIO took 6708.684 ms
[40.44140625, 40.44140625, 48.0703125, 48.0703125, 48.0703125, 48.0703125, 48.0703125, 48.0703125, 48.0703125, 48.0703125, 48.0703125, 48.0703125, 48.0703125, 48.0703125, 48.0703125, 48.0703125]