1# Copyright 2012 the V8 project authors. All rights reserved.
2# Redistribution and use in source and binary forms, with or without
3# modification, are permitted provided that the following conditions are
4# met:
5#
6#     * Redistributions of source code must retain the above copyright
7#       notice, this list of conditions and the following disclaimer.
8#     * Redistributions in binary form must reproduce the above
9#       copyright notice, this list of conditions and the following
10#       disclaimer in the documentation and/or other materials provided
11#       with the distribution.
12#     * Neither the name of Google Inc. nor the names of its
13#       contributors may be used to endorse or promote products derived
14#       from this software without specific prior written permission.
15#
16# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
17# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
18# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
19# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
20# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
21# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
22# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
26# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27
28
29import os
30import shelve
31import threading
32
33
34class PerfDataEntry(object):
35  def __init__(self):
36    self.avg = 0.0
37    self.count = 0
38
39  def AddResult(self, result):
40    kLearnRateLimiter = 99  # Greater value means slower learning.
41    # We use an approximation of the average of the last 100 results here:
42    # The existing average is weighted with kLearnRateLimiter (or less
43    # if there are fewer data points).
44    effective_count = min(self.count, kLearnRateLimiter)
45    self.avg = self.avg * effective_count + result
46    self.count = effective_count + 1
47    self.avg /= self.count
48
49
50class PerfDataStore(object):
51  def __init__(self, datadir, arch, mode):
52    filename = os.path.join(datadir, "%s.%s.perfdata" % (arch, mode))
53    self.database = shelve.open(filename, protocol=2)
54    self.closed = False
55    self.lock = threading.Lock()
56
57  def __del__(self):
58    self.close()
59
60  def close(self):
61    if self.closed: return
62    self.database.close()
63    self.closed = True
64
65  def GetKey(self, test):
66    """Computes the key used to access data for the given testcase."""
67    flags = "".join(test.flags)
68    return str("%s.%s.%s" % (test.suitename(), test.path, flags))
69
70  def FetchPerfData(self, test):
71    """Returns the observed duration for |test| as read from the store."""
72    key = self.GetKey(test)
73    if key in self.database:
74      return self.database[key].avg
75    return None
76
77  def UpdatePerfData(self, test):
78    """Updates the persisted value in the store with test.duration."""
79    testkey = self.GetKey(test)
80    self.RawUpdatePerfData(testkey, test.duration)
81
82  def RawUpdatePerfData(self, testkey, duration):
83    with self.lock:
84      if testkey in self.database:
85        entry = self.database[testkey]
86      else:
87        entry = PerfDataEntry()
88      entry.AddResult(duration)
89      self.database[testkey] = entry
90
91
92class PerfDataManager(object):
93  def __init__(self, datadir):
94    self.datadir = os.path.abspath(datadir)
95    if not os.path.exists(self.datadir):
96      os.makedirs(self.datadir)
97    self.stores = {}  # Keyed by arch, then mode.
98    self.closed = False
99    self.lock = threading.Lock()
100
101  def __del__(self):
102    self.close()
103
104  def close(self):
105    if self.closed: return
106    for arch in self.stores:
107      modes = self.stores[arch]
108      for mode in modes:
109        store = modes[mode]
110        store.close()
111    self.closed = True
112
113  def GetStore(self, arch, mode):
114    with self.lock:
115      if not arch in self.stores:
116        self.stores[arch] = {}
117      modes = self.stores[arch]
118      if not mode in modes:
119        modes[mode] = PerfDataStore(self.datadir, arch, mode)
120      return modes[mode]
121