#!/usr/bin/env python3
import os
import time
import cProfile
import mmap
def ioTest():
    m = mmap.mmap(-1, 1024*1024)
    block = bytes('A'*1024*1024, 'utf-8')
    m.write(block)
    filename = 'test.bin'
    f = os.open(filename, os.O_WRONLY | os.O_CREAT | os.O_TRUNC |
                os.O_SYNC, os.O_DIRECT`)
    start = time.time()
    for x in range(500):
        os.write(f,m)
    os.close(f)
    transferTime_sec = time.time() - start
    msg = 'Wrote {:0f}MB in {:0.03f}s.'
    print(msg.format(os.stat(filename).st_size/1024/1024,
                     transferTime_sec))
ioTest()