output.txt

01e8e2aa-cd8c-c37e-4689-5db093f8847f
01e8e2aa-cd8c-c6bc-4689-5db093f88480
01e8e2aa-cd8c-c842-4689-5db093f88481
01e8e2aa-cd8c-c98c-4689-5db093f88482
01e8e2aa-cd8c-cb30-4689-5db093f88483
gen_uuid() -> 0.047747763
uuid.uuid1() -> 0.06972335500000001
uuid.uuid4() -> 0.10280339599999999
ObjectId() -> 0.05833711899999999
uuid0.generate() -> 0.12896245299999998

sequuid.py

import os
import uuid
import time
import struct
import threading


_local = threading.local()


def gen_uuid():
    """Generates time-ordered UUIDs

    Contains:
    - 8 bytes - count of 100ns intervals since 1582-10-15
    - 4 bytes - randomly generated once per thread
    - 4 bytes - cyclic counter which starts from random number

    """
    try:
        _local.thread_id
    except AttributeError:
        _local.thread_id = struct.unpack('>I', os.urandom(4))[0]
        _local.counter = struct.unpack('>I', os.urandom(4))[0]

    # 0x01b21dd213814000 is the number of 100-ns intervals between the
    # UUID epoch 1582-10-15 00:00:00 and the Unix epoch 1970-01-01 00:00:00
    epoch = 0x01b21dd213814000
    now = int(time.time() * 10000000)

    _local.counter = (_local.counter + 1) % 0xFFFFFFFF
    return uuid.UUID(int=(((now + epoch) << 64)
                          + (_local.thread_id << 32)
                          + _local.counter))


if __name__ == '__main__':
    for _ in range(5):
        print(gen_uuid())

    import timeit
    import uuid0
    from bson.objectid import ObjectId

    for code in [
        'gen_uuid()',
        'uuid.uuid1()',
        'uuid.uuid4()',
        'ObjectId()',
        'uuid0.generate()',
    ]:
        print('{} ->'.format(code),
              timeit.timeit(code, number=10000, globals=globals()))