tools/power/mach_commands.py

   1 # This Source Code Form is subject to the terms of the Mozilla Public
   2 # License, v. 2.0. If a copy of the MPL was not distributed with this
   3 # file, You can obtain one at http://mozilla.org/MPL/2.0/.
   4
   5 from __future__ import print_function, absolute_import
   6
   7 from distutils.version import StrictVersion
   8
   9 from mach.decorators import (
  10     Command,
  11     CommandArgument,
  12     CommandProvider,
  13 )
  14 from mozbuild.base import MachCommandBase
  15
  16
  17 def is_osx_10_10_or_greater(cls):
  18     import platform
  19
  20     release = platform.mac_ver()[0]
  21     return release and StrictVersion(release) >= StrictVersion("10.10")
  22
  23
  24 @CommandProvider
  25 class MachCommands(MachCommandBase):
  26     """
  27     Get system power consumption and related measurements.
  28     """
  29
  30     @Command(
  31         "power",
  32         category="misc",
  33         conditions=[is_osx_10_10_or_greater],
  34         description="Get system power consumption and related measurements for "
  35         "all running browsers. Available only on Mac OS X 10.10 and above. "
  36         "Requires root access.",
  37     )
  38     @CommandArgument(
  39         "-i",
  40         "--interval",
  41         type=int,
  42         default=30000,
  43         help="The sample period, measured in milliseconds. Defaults to 30000.",
  44     )
  45     def power(self, command_context, interval):
  46         import os
  47         import re
  48         import subprocess
  49
  50         rapl = os.path.join(self.topobjdir, "dist", "bin", "rapl")
  51
  52         interval = str(interval)
  53
  54         # Run a trivial command with |sudo| to gain temporary root privileges
  55         # before |rapl| and |powermetrics| are called. This ensures that |rapl|
  56         # doesn't start measuring while |powermetrics| is waiting for the root
  57         # password to be entered.
  58         try:
  59             subprocess.check_call(["sudo", "true"])
  60         except Exception:
  61             print("\nsudo failed; aborting")
  62             return 1
  63
  64         # This runs rapl in the background because nothing in this script
  65         # depends on the output. This is good because we want |rapl| and
  66         # |powermetrics| to run at the same time.
  67         subprocess.Popen([rapl, "-n", "1", "-i", interval])
  68
  69         lines = subprocess.check_output(
  70             [
  71                 "sudo",
  72                 "powermetrics",
  73                 "--samplers",
  74                 "tasks",
  75                 "--show-process-coalition",
  76                 "--show-process-gpu",
  77                 "-n",
  78                 "1",
  79                 "-i",
  80                 interval,
  81             ],
  82             universal_newlines=True,
  83         )
  84
  85         # When run with --show-process-coalition, |powermetrics| groups outputs
  86         # into process coalitions, each of which has a leader.
  87         #
  88         # For example, when Firefox runs from the dock, its coalition looks
  89         # like this:
  90         #
  91         #   org.mozilla.firefox
  92         #     firefox
  93         #     plugin-container
  94         #
  95         # When Safari runs from the dock:
  96         #
  97         #   com.apple.Safari
  98         #     Safari
  99         #     com.apple.WebKit.Networking
 100         #     com.apple.WebKit.WebContent
 101         #     com.apple.WebKit.WebContent
 102         #
 103         # When Chrome runs from the dock:
 104         #
 105         #   com.google.Chrome
 106         #     Google Chrome
 107         #     Google Chrome Helper
 108         #     Google Chrome Helper
 109         #
 110         # In these cases, we want to print the whole coalition.
 111         #
 112         # Also, when you run any of them from the command line, things are the
 113         # same except that the leader is com.apple.Terminal and there may be
 114         # non-browser processes in the coalition, e.g.:
 115         #
 116         #  com.apple.Terminal
 117         #    firefox
 118         #    plugin-container
 119         #    <and possibly other, non-browser processes>
 120         #
 121         # Also, the WindowServer and kernel coalitions and processes are often
 122         # relevant.
 123         #
 124         # We want to print all these but omit uninteresting coalitions. We
 125         # could do this by properly parsing powermetrics output, but it's
 126         # simpler and more robust to just grep for a handful of identifying
 127         # strings.
 128
 129         print()  # blank line between |rapl| output and |powermetrics| output
 130
 131         for line in lines.splitlines():
 132             # Search for the following things.
 133             #
 134             # - '^Name' is for the columns headings line.
 135             #
 136             # - 'firefox' and 'plugin-container' are for Firefox
 137             #
 138             # - 'Safari\b' and 'WebKit' are for Safari. The '\b' excludes
 139             #   SafariCloudHistoryPush, which is a process that always
 140             #   runs, even when Safari isn't open.
 141             #
 142             # - 'Chrome' is for Chrome.
 143             #
 144             # - 'Terminal' is for the terminal. If no browser is running from
 145             #   within the terminal, it will show up unnecessarily. This is a
 146             #   minor disadvantage of this very simple parsing strategy.
 147             #
 148             # - 'WindowServer' is for the WindowServer.
 149             #
 150             # - 'kernel' is for the kernel.
 151             #
 152             if re.search(
 153                 r"(^Name|firefox|plugin-container|Safari\b|WebKit|Chrome|Terminal|WindowServer|kernel)",  # NOQA: E501
 154                 line,
 155             ):
 156                 print(line)
 157
 158         return 0