CNP_hash.py

import struct
import hashlib
from datetime import datetime

t = datetime.now()
ci = 0

for i in xrange(0, 2**42):
    buf = struct.pack('Q', i)
    m = hashlib.sha256()
    m.update(buf)
    m.digest()

    tn = datetime.now()
    dt = tn -t
    if dt.seconds >= 5:
        print '%.3f KHashes/sec' % ((i - ci) / 5. / 10**3)
        ci = i
        t = tn