build/android/pylib/utils/time_profile.py

   1 # Copyright (c) 2013 The Chromium Authors. All rights reserved.
   2 # Use of this source code is governed by a BSD-style license that can be
   3 # found in the LICENSE file.
   4
   5 import logging
   6 import time
   7
   8
   9 class TimeProfile(object):
  10   """Class for simple profiling of action, with logging of cost."""
  11
  12   def __init__(self, description='operation'):
  13     self._starttime = None
  14     self._endtime = None
  15     self._description = description
  16     self.Start()
  17
  18   def Start(self):
  19     self._starttime = time.time()
  20     self._endtime = None
  21
  22   def GetDelta(self):
  23     """Returns the rounded delta.
  24
  25     Also stops the timer if Stop() has not already been called.
  26     """
  27     if self._endtime is None:
  28       self.Stop(log=False)
  29     delta = self._endtime - self._starttime
  30     delta = round(delta, 2) if delta < 10 else round(delta, 1)
  31     return delta
  32
  33   def LogResult(self):
  34     """Logs the result."""
  35     logging.info('%s seconds to perform %s', self.GetDelta(), self._description)
  36
  37   def Stop(self, log=True):
  38     """Stop profiling.
  39
  40     Args:
  41       log: Log the delta (defaults to true).
  42     """
  43     self._endtime = time.time()
  44     if log:
  45       self.LogResult()