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# This Source Code Form is subject to the terms of the Mozilla Public
# License, v. 2.0. If a copy of the MPL was not distributed with this
from mach.decorators import Command, CommandArgument
from packaging.version import Version
def is_osx_10_10_or_greater(cls):
import platform
release = platform.mac_ver()[0]
return release and Version(release) >= Version("10.10")
# Get system power consumption and related measurements.
@Command(
"power",
category="misc",
conditions=[is_osx_10_10_or_greater],
description="Get system power consumption and related measurements for "
"all running browsers. Available only on Mac OS X 10.10 and above. "
"Requires root access.",
)
@CommandArgument(
"-i",
"--interval",
type=int,
default=30000,
help="The sample period, measured in milliseconds. Defaults to 30000.",
)
def power(command_context, interval):
"""
Get system power consumption and related measurements.
"""
import os
import re
import subprocess
rapl = os.path.join(command_context.topobjdir, "dist", "bin", "rapl")
interval = str(interval)
# Run a trivial command with |sudo| to gain temporary root privileges
# before |rapl| and |powermetrics| are called. This ensures that |rapl|
# doesn't start measuring while |powermetrics| is waiting for the root
# password to be entered.
try:
subprocess.check_call(["sudo", "true"])
except Exception:
print("\nsudo failed; aborting")
return 1
# This runs rapl in the background because nothing in this script
# depends on the output. This is good because we want |rapl| and
# |powermetrics| to run at the same time.
subprocess.Popen([rapl, "-n", "1", "-i", interval])
lines = subprocess.check_output(
[
"sudo",
"powermetrics",
"--samplers",
"tasks",
"--show-process-coalition",
"--show-process-gpu",
"-n",
"1",
"-i",
interval,
],
universal_newlines=True,
)
# When run with --show-process-coalition, |powermetrics| groups outputs
# into process coalitions, each of which has a leader.
#
# For example, when Firefox runs from the dock, its coalition looks
# like this:
#
# org.mozilla.firefox
# firefox
# plugin-container
#
# When Safari runs from the dock:
#
# com.apple.Safari
# Safari
# com.apple.WebKit.Networking
# com.apple.WebKit.WebContent
# com.apple.WebKit.WebContent
#
# When Chrome runs from the dock:
#
# com.google.Chrome
# Google Chrome
# Google Chrome Helper
# Google Chrome Helper
#
# In these cases, we want to print the whole coalition.
#
# Also, when you run any of them from the command line, things are the
# same except that the leader is com.apple.Terminal and there may be
# non-browser processes in the coalition, e.g.:
#
# com.apple.Terminal
# firefox
# plugin-container
# <and possibly other, non-browser processes>
#
# Also, the WindowServer and kernel coalitions and processes are often
# relevant.
#
# We want to print all these but omit uninteresting coalitions. We
# could do this by properly parsing powermetrics output, but it's
# simpler and more robust to just grep for a handful of identifying
# strings.
print() # blank line between |rapl| output and |powermetrics| output
for line in lines.splitlines():
# Search for the following things.
#
# - '^Name' is for the columns headings line.
#
# - 'firefox' and 'plugin-container' are for Firefox
#
# - 'Safari\b' and 'WebKit' are for Safari. The '\b' excludes
# SafariCloudHistoryPush, which is a process that always
# runs, even when Safari isn't open.
#
# - 'Chrome' is for Chrome.
#
# - 'Terminal' is for the terminal. If no browser is running from
# within the terminal, it will show up unnecessarily. This is a
# minor disadvantage of this very simple parsing strategy.
#
# - 'WindowServer' is for the WindowServer.
#
# - 'kernel' is for the kernel.
#
if re.search(
r"(^Name|firefox|plugin-container|Safari\b|WebKit|Chrome|Terminal|WindowServer|kernel)", # NOQA: E501
line,
):
print(line)
return 0