from __future__ import division

def show_pickle_sizes (obj, indent="",
    display_if_size_greater_than=10000) :
  """
  Function for debugging issues with pickle file size, e.g. detecting which
  objects are contributing to bloat.  This is very approximate, and somewhat
  misleading since child objects may appear to be larger than their parents,
  probably for some reason involving duplicated references.
  """
  from cPickle import dumps
  if hasattr(obj, "__slots__") :
    attr_names = obj.__slots__
  else :
    attr_names = obj.__dict__.keys()
  for attr in attr_names :
    child_obj = getattr(obj, attr, None)
    if (child_obj is not None) :
      pkl = dumps(child_obj)
      n_bytes = len(pkl)
      if (n_bytes > display_if_size_greater_than) :
        print indent+attr, n_bytes
        if isinstance(child_obj, object) and hasattr(child_obj, "__dict__") :
          show_pickle_sizes(child_obj, indent+"  ",
            display_if_size_greater_than=display_if_size_greater_than)
        elif isinstance(child_obj, list) :
          for item in child_obj :
            n_bytes_item = len(dumps(item))
            if (n_bytes_item > display_if_size_greater_than) :
              print indent+"  "+type(item).__name__, n_bytes_item
              if isinstance(item, object) and hasattr(item, "__dict__") :
                show_pickle_sizes(item, indent+"    ",
                  display_if_size_greater_than=display_if_size_greater_than)