sdk/platform-tools/systrace/catapult/telemetry/telemetry/timeline/counter.py

   1 # Copyright 2014 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 telemetry.timeline.event_container as event_container
   6
   7
   8 # Doesn't inherit from TimelineEvent because its only a temporary wrapper of a
   9 # counter sample into an event. During stable operation, the samples are stored
  10 # a dense array of values rather than in the long-form done by an Event.
  11 class CounterSample(object):
  12   def __init__(self, counter, sample_index):
  13     self._counter = counter
  14     self._sample_index = sample_index
  15
  16   @property
  17   def category(self):
  18     return self._counter.category
  19
  20   @property
  21   def name(self):
  22     return self._counter.full_name
  23
  24   @property
  25   def value(self):
  26     return self._counter.samples[self._sample_index]
  27
  28   @property
  29   def start(self):
  30     return self._counter.timestamps[self._sample_index]
  31
  32   @start.setter
  33   def start(self, start):
  34     self._counter.timestamps[self._sample_index] = start
  35
  36   @property
  37   def duration(self):
  38     return 0
  39
  40   @property
  41   def end(self):
  42     return self.start
  43
  44   @property
  45   def thread_start(self):
  46     return None
  47
  48   @property
  49   def thread_duration(self):
  50     return None
  51
  52   @property
  53   def thread_end(self):
  54     return None
  55
  56
  57 class Counter(event_container.TimelineEventContainer):
  58   """ Stores all the samples for a given counter.
  59   """
  60   def __init__(self, parent, category, name):
  61     super(Counter, self).__init__(name, parent)
  62     self.category = category
  63     self.full_name = category + '.' + name
  64     self.samples = []
  65     self.timestamps = []
  66     self.series_names = []
  67     self.totals = []
  68     self.max_total = 0
  69
  70   def IterChildContainers(self):
  71     return
  72     yield # pylint: disable=unreachable
  73
  74   def IterEventsInThisContainer(self, event_type_predicate, event_predicate):
  75     if not event_type_predicate(CounterSample) or not self.timestamps:
  76       return
  77
  78     # Pass event_predicate a reused CounterSample instance to avoid
  79     # creating a ton of garbage for rejected samples.
  80     test_sample = CounterSample(self, 0)
  81     for i in xrange(len(self.timestamps)):
  82       test_sample._sample_index = i  # pylint: disable=protected-access
  83       if event_predicate(test_sample):
  84         yield CounterSample(self, i)
  85
  86   @property
  87   def num_series(self):
  88     return len(self.series_names)
  89
  90   @property
  91   def num_samples(self):
  92     return len(self.timestamps)
  93
  94   def FinalizeImport(self):
  95     if self.num_series * self.num_samples != len(self.samples):
  96       raise ValueError(
  97           'Length of samples must be a multiple of length of timestamps.')
  98
  99     self.totals = []
 100     self.max_total = 0
 101     if not len(self.samples):
 102       return
 103
 104     max_total = None
 105     for i in xrange(self.num_samples):
 106       total = 0
 107       for j in xrange(self.num_series):
 108         total += self.samples[i * self.num_series + j]
 109         self.totals.append(total)
 110       if max_total is None or total > max_total:
 111         max_total = total
 112     self.max_total = max_total