old_contents: from vbench.api import Benchmark
  from datetime import datetime
  
  common_setup = """from pandas_vb_common import *
  from datetime import timedelta
  
  N = 1000000
  
  try:
      rng = date_range('1/1/2000', periods=N, freq='min')
  except NameError:
      rng = DateRange('1/1/2000', periods=N, offset=datetools.Minute())
      date_range = DateRange
  
  ts = Series(np.random.randn(N), index=rng)
  
  def replace_slow(ser, old, new):
      lib.slow_replace(ser.values, old, new)
      return ser
  """
  
  replace_fillna = Benchmark('ts.fillna(0., inplace=True)', common_setup,
                             start_date=datetime(2012, 4, 4))
  replace_replacena = Benchmark('ts.replace(np.nan, 0., inplace=True)',
                                common_setup,
                                start_date=datetime(2012, 5, 15))
  
  # replace_putmask = Benchmark('replace_slow(ts, np.nan, 0.)', common_setup,
  #                             start_date=datetime(2012, 5, 15))
  
new_contents: from vbench.api import Benchmark
  from datetime import datetime
  
  common_setup = """from pandas_vb_common import *
  from datetime import timedelta
  
  N = 1000000
  
  try:
      rng = date_range('1/1/2000', periods=N, freq='min')
  except NameError:
      rng = DateRange('1/1/2000', periods=N, offset=datetools.Minute())
      date_range = DateRange
  
  ts = Series(np.random.randn(N), index=rng)
  """
  
  large_dict_setup = """from pandas_vb_common import *
  from pandas.compat import range
  n = 10 ** 6
  start_value = 10 ** 5
  to_rep = dict((i, start_value + i) for i in range(n))
  s = Series(np.random.randint(n, size=10 ** 3))
  """
  
  replace_fillna = Benchmark('ts.fillna(0., inplace=True)', common_setup,
                             name='replace_fillna',
                             start_date=datetime(2012, 4, 4))
  replace_replacena = Benchmark('ts.replace(np.nan, 0., inplace=True)',
                                common_setup,
                                name='replace_replacena',
                                start_date=datetime(2012, 5, 15))
  replace_large_dict = Benchmark('s.replace(to_rep, inplace=True)',
                                 large_dict_setup,
                                 name='replace_large_dict',
                                 start_date=datetime(2014, 4, 6))
  
subject: add vbench for issue 6697