Construction time benchmark for frozenmap (immutables.Map)

frozenmap_construction_bench.py

"""Created for the purpose of comparing the construction time
between ``dict``, ``ChainMap``, and the proposed ``frozenmap`` in PEP-603.
"""

import sys
import time
import collections

import immutables

# Could improve accuracy by running multiple iterations per test
# and getting the average rather than a single run for each N
for N in [1, 5, 10, 100, 1_000, 10_000, 100_000, 1_000_000]:
    print('=============')
    print(f'  # of items: {N}')
    print()

    start = time.monotonic()
    d = dict()
    for i in range(N):
          d[chr(i)] = i
    total = time.monotonic() - start
    
    assert(len(d) == N)
    print(f'  dict construction time: {total:.8f}s')

    start = time.monotonic()
    c = collections.ChainMap()
    for i in range(N):
          c[chr(i)] = i
    total = time.monotonic() - start
    
    assert(len(c) == N)
    print(f'  ChainMap construction time: {total:.8f}s')

    start = time.monotonic()
    h = immutables.Map()
    hm = h.mutate()
    for i in range(N):
          hm[chr(i)] = i
    h = hm.finish()
    total = time.monotonic() - start
    
    assert(len(h) == N)
    print(f'  frozenmap construction time: {total:.8f}s')

Performance results:

OS: Arch Linux 5.3.0
CPU: Intel i5-4460
RAM: 16G

=============
  # of items: 1

  dict construction time: 0.00000321s
  ChainMap construction time: 0.00001516s
  frozenmap construction time: 0.00000386s
=============
  # of items: 5

  dict construction time: 0.00000279s
  ChainMap construction time: 0.00000553s
  frozenmap construction time: 0.00000340s
=============
  # of items: 10

  dict construction time: 0.00000360s
  ChainMap construction time: 0.00000689s
  frozenmap construction time: 0.00001401s
=============
  # of items: 100

  dict construction time: 0.00004714s
  ChainMap construction time: 0.00008749s
  frozenmap construction time: 0.00004118s
=============
  # of items: 1000

  dict construction time: 0.00031701s
  ChainMap construction time: 0.00051719s
  frozenmap construction time: 0.00054686s
=============
  # of items: 10000

  dict construction time: 0.00312743s
  ChainMap construction time: 0.00523761s
  frozenmap construction time: 0.00452464s
=============
  # of items: 100000

  dict construction time: 0.03632125s
  ChainMap construction time: 0.06007221s
  frozenmap construction time: 0.06947755s
=============
  # of items: 1000000

  dict construction time: 0.39704744s
  ChainMap construction time: 0.61989591s
  frozenmap construction time: 2.51226446s