src/third_party/blink/Tools/Scripts/webkitpy/performance_tests/perftest.py - cobalt - Git at Google

 # Copyright (C) 2012 Google Inc. All rights reserved.
 # Copyright (C) 2012 Zoltan Horvath, Adobe Systems Incorporated. All rights reserved.
 #
 # Redistribution and use in source and binary forms, with or without
 # modification, are permitted provided that the following conditions are
 # met:
 #
 #     * Redistributions of source code must retain the above copyright
 # notice, this list of conditions and the following disclaimer.
 #     * Redistributions in binary form must reproduce the above
 # copyright notice, this list of conditions and the following disclaimer
 # in the documentation and/or other materials provided with the
 # distribution.
 #     * Neither the name of Google Inc. nor the names of its
 # contributors may be used to endorse or promote products derived from
 # this software without specific prior written permission.
 #
 # THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 # "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 # LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 # A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 # OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 # SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 # LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 # DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 # THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 # (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.


 import errno
 import logging
 import math
 import re
 import os
 import signal
 import socket
 import subprocess
 import sys
 import time

 from webkitpy.layout_tests.controllers.test_result_writer import TestResultWriter
 from webkitpy.layout_tests.port.driver import DriverInput
 from webkitpy.layout_tests.port.driver import DriverOutput

 DEFAULT_TEST_RUNNER_COUNT = 4

 _log = logging.getLogger(__name__)


 class PerfTestMetric(object):
     def __init__(self, metric, unit=None, iterations=None):
         # FIXME: Fix runner.js to report correct metric names
         self._iterations = iterations or []
         self._unit = unit or self.metric_to_unit(metric)
         self._metric = self.time_unit_to_metric(self._unit) if metric == 'Time' else metric

     def name(self):
         return self._metric

     def has_values(self):
         return bool(self._iterations)

     def append_group(self, group_values):
         assert isinstance(group_values, list)
         self._iterations.append(group_values)

     def grouped_iteration_values(self):
         return self._iterations

     def flattened_iteration_values(self):
         return [value for group_values in self._iterations for value in group_values]

     def unit(self):
         return self._unit

     @staticmethod
     def metric_to_unit(metric):
         assert metric in ('Time', 'Malloc', 'JSHeap')
         return 'ms' if metric == 'Time' else 'bytes'

     @staticmethod
     def time_unit_to_metric(unit):
         return {'fps': 'FrameRate', 'runs/s': 'Runs', 'ms': 'Time'}[unit]


 class PerfTest(object):

     def __init__(self, port, test_name, test_path, test_runner_count=DEFAULT_TEST_RUNNER_COUNT):
         self._port = port
         self._test_name = test_name
         self._test_path = test_path
         self._description = None
         self._metrics = {}
         self._ordered_metrics_name = []
         self._test_runner_count = test_runner_count

     def test_name(self):
         return self._test_name

     def test_name_without_file_extension(self):
         return re.sub(r'\.\w+$', '', self.test_name())

     def test_path(self):
         return self._test_path

     def description(self):
         return self._description

     def prepare(self, time_out_ms):
         return True

     def _create_driver(self):
         return self._port.create_driver(worker_number=0, no_timeout=True)

     def run(self, time_out_ms):
         for _ in xrange(self._test_runner_count):
             driver = self._create_driver()
             try:
                 if not self._run_with_driver(driver, time_out_ms):
                     return None
             finally:
                 driver.stop()

         should_log = not self._port.get_option('profile')
         if should_log and self._description:
             _log.info('DESCRIPTION: %s' % self._description)

         results = {}
         for metric_name in self._ordered_metrics_name:
             metric = self._metrics[metric_name]
             results[metric.name()] = metric.grouped_iteration_values()
             if should_log:
                 legacy_chromium_bot_compatible_name = self.test_name_without_file_extension().replace('/', ': ')
                 self.log_statistics(legacy_chromium_bot_compatible_name + ': ' + metric.name(),
                     metric.flattened_iteration_values(), metric.unit())

         return results

     @staticmethod
     def log_statistics(test_name, values, unit):
         sorted_values = sorted(values)

         # Compute the mean and variance using Knuth's online algorithm (has good numerical stability).
         square_sum = 0
         mean = 0
         for i, time in enumerate(sorted_values):
             delta = time - mean
             sweep = i + 1.0
             mean += delta / sweep
             square_sum += delta * (time - mean)

         middle = int(len(sorted_values) / 2)
         mean = sum(sorted_values) / len(values)
         median = sorted_values[middle] if len(sorted_values) % 2 else (sorted_values[middle - 1] + sorted_values[middle]) / 2
         stdev = math.sqrt(square_sum / (len(sorted_values) - 1)) if len(sorted_values) > 1 else 0

         _log.info('RESULT %s= %s %s' % (test_name, mean, unit))
         _log.info('median= %s %s, stdev= %s %s, min= %s %s, max= %s %s' %
             (median, unit, stdev, unit, sorted_values[0], unit, sorted_values[-1], unit))

     _description_regex = re.compile(r'^Description: (?P<description>.*)$', re.IGNORECASE)
     _metrics_regex = re.compile(r'^(?P<metric>Time|Malloc|JS Heap):')
     _statistics_keys = ['avg', 'median', 'stdev', 'min', 'max', 'unit', 'values']
     _score_regex = re.compile(r'^(?P<key>' + r'|'.join(_statistics_keys) + r')\s+(?P<value>([0-9\.]+(,\s+)?)+)\s*(?P<unit>.*)')
     _console_regex = re.compile(r'^CONSOLE (MESSAGE|WARNING):')

     def _run_with_driver(self, driver, time_out_ms):
         output = self.run_single(driver, self.test_path(), time_out_ms)
         self._filter_output(output)
         if self.run_failed(output):
             return False

         current_metric = None
         for line in re.split('\n', output.text):
             description_match = self._description_regex.match(line)
             metric_match = self._metrics_regex.match(line)
             score = self._score_regex.match(line)
             console_match = self._console_regex.match(line)

             if description_match:
                 self._description = description_match.group('description')
             elif metric_match:
                 current_metric = metric_match.group('metric').replace(' ', '')
             elif score:
                 if score.group('key') != 'values':
                     continue

                 metric = self._ensure_metrics(current_metric, score.group('unit'))
                 metric.append_group(map(lambda value: float(value), score.group('value').split(', ')))
             elif console_match:
                 # Ignore console messages such as deprecation warnings.
                 continue
             else:
                 _log.error('ERROR: ' + line)
                 return False

         return True

     def _ensure_metrics(self, metric_name, unit=None):
         if metric_name not in self._metrics:
             self._metrics[metric_name] = PerfTestMetric(metric_name, unit)
             self._ordered_metrics_name.append(metric_name)
         return self._metrics[metric_name]

     def run_single(self, driver, test_path, time_out_ms, should_run_pixel_test=False):
         return driver.run_test(DriverInput(test_path, time_out_ms, image_hash=None, should_run_pixel_test=should_run_pixel_test, args=[]), stop_when_done=False)

     def run_failed(self, output):
         if output.error:
             _log.error('error: %s\n%s' % (self.test_name(), output.error))

         if output.text == None:
             pass
         elif output.timeout:
             _log.error('timeout: %s' % self.test_name())
         elif output.crash:
             _log.error('crash: %s' % self.test_name())
         else:
             return False

         return True

     @staticmethod
     def _should_ignore_line(regexps, line):
         if not line:
             return True
         for regexp in regexps:
             if regexp.search(line):
                 return True
         return False

     _lines_to_ignore_in_stderr = [
         re.compile(r'^Unknown option:'),
         re.compile(r'^\[WARNING:proxy_service.cc'),
         re.compile(r'^\[INFO:'),
         # These stderr messages come from content_shell on Linux.
         re.compile(r'INFO:SkFontHost_fontconfig.cpp'),
         re.compile(r'Running without the SUID sandbox'),
         # crbug.com/345229
         re.compile(r'InitializeSandbox\(\) called with multiple threads in process gpu-process')]

     _lines_to_ignore_in_parser_result = [
         re.compile(r'^\s*Running \d+ times$'),
         re.compile(r'^\s*Ignoring warm-up '),
         re.compile(r'^\s*Info:'),
         re.compile(r'^\s*\d+(.\d+)?(\s*(runs\/s|ms|fps))?$'),
         # Following are for handle existing test like Dromaeo
         re.compile(re.escape("""main frame - has 1 onunload handler(s)""")),
         re.compile(re.escape("""frame "<!--framePath //<!--frame0-->-->" - has 1 onunload handler(s)""")),
         re.compile(re.escape("""frame "<!--framePath //<!--frame0-->/<!--frame0-->-->" - has 1 onunload handler(s)""")),
         # Following is for html5.html
         re.compile(re.escape("""Blocked access to external URL http://www.whatwg.org/specs/web-apps/current-work/""")),
         re.compile(r"CONSOLE MESSAGE: (line \d+: )?Blocked script execution in '[A-Za-z0-9\-\.:]+' because the document's frame is sandboxed and the 'allow-scripts' permission is not set."),
         re.compile(r"CONSOLE MESSAGE: (line \d+: )?Not allowed to load local resource"),
         # Dromaeo reports values for subtests. Ignore them for now.
         re.compile(r'(?P<name>.+): \[(?P<values>(\d+(.\d+)?,\s+)*\d+(.\d+)?)\]'),
     ]

     def _filter_output(self, output):
         if output.error:
             output.error = '\n'.join([line for line in re.split('\n', output.error) if not self._should_ignore_line(self._lines_to_ignore_in_stderr, line)])
         if output.text:
             output.text = '\n'.join([line for line in re.split('\n', output.text) if not self._should_ignore_line(self._lines_to_ignore_in_parser_result, line)])


 class SingleProcessPerfTest(PerfTest):
     def __init__(self, port, test_name, test_path, test_runner_count=1):
         super(SingleProcessPerfTest, self).__init__(port, test_name, test_path, test_runner_count)


 class ChromiumStylePerfTest(PerfTest):
     _chromium_style_result_regex = re.compile(r'^RESULT\s+(?P<name>[^=]+)\s*=\s+(?P<value>\d+(\.\d+)?)\s*(?P<unit>\w+)$')

     def __init__(self, port, test_name, test_path, test_runner_count=DEFAULT_TEST_RUNNER_COUNT):
         super(ChromiumStylePerfTest, self).__init__(port, test_name, test_path, test_runner_count)

     def run(self, time_out_ms):
         driver = self._create_driver()
         try:
             output = self.run_single(driver, self.test_path(), time_out_ms)
         finally:
             driver.stop()

         self._filter_output(output)
         if self.run_failed(output):
             return None

         return self.parse_and_log_output(output)

     def parse_and_log_output(self, output):
         test_failed = False
         results = {}
         for line in re.split('\n', output.text):
             resultLine = ChromiumStylePerfTest._chromium_style_result_regex.match(line)
             if resultLine:
                 # FIXME: Store the unit
                 results[resultLine.group('name').replace(' ', '')] = float(resultLine.group('value'))
                 _log.info(line)
             elif not len(line) == 0:
                 test_failed = True
                 _log.error(line)
         return results if results and not test_failed else None


 class PerfTestFactory(object):

     _pattern_map = [
         (re.compile(r'^Dromaeo/'), SingleProcessPerfTest),
         (re.compile(r'^inspector/'), ChromiumStylePerfTest),
     ]

     @classmethod
     def create_perf_test(cls, port, test_name, path, test_runner_count=DEFAULT_TEST_RUNNER_COUNT):
         for (pattern, test_class) in cls._pattern_map:
             if pattern.match(test_name):
                 return test_class(port, test_name, path, test_runner_count)
         return PerfTest(port, test_name, path, test_runner_count)
	# Copyright (C) 2012 Google Inc. All rights reserved.
	# Copyright (C) 2012 Zoltan Horvath, Adobe Systems Incorporated. All rights reserved.
	#
	# Redistribution and use in source and binary forms, with or without
	# modification, are permitted provided that the following conditions are
	# met:
	#
	# * Redistributions of source code must retain the above copyright
	# notice, this list of conditions and the following disclaimer.
	# * Redistributions in binary form must reproduce the above
	# copyright notice, this list of conditions and the following disclaimer
	# in the documentation and/or other materials provided with the
	# distribution.
	# * Neither the name of Google Inc. nor the names of its
	# contributors may be used to endorse or promote products derived from
	# this software without specific prior written permission.
	#
	# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
	# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
	# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
	# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
	# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
	# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
	# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
	# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
	# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
	# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
	# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.


	import errno
	import logging
	import math
	import re
	import os
	import signal
	import socket
	import subprocess
	import sys
	import time

	from webkitpy.layout_tests.controllers.test_result_writer import TestResultWriter
	from webkitpy.layout_tests.port.driver import DriverInput
	from webkitpy.layout_tests.port.driver import DriverOutput

	DEFAULT_TEST_RUNNER_COUNT = 4

	_log = logging.getLogger(__name__)


	class PerfTestMetric(object):
	def __init__(self, metric, unit=None, iterations=None):
	# FIXME: Fix runner.js to report correct metric names
	self._iterations = iterations or []
	self._unit = unit or self.metric_to_unit(metric)
	self._metric = self.time_unit_to_metric(self._unit) if metric == 'Time' else metric

	def name(self):
	return self._metric

	def has_values(self):
	return bool(self._iterations)

	def append_group(self, group_values):
	assert isinstance(group_values, list)
	self._iterations.append(group_values)

	def grouped_iteration_values(self):
	return self._iterations

	def flattened_iteration_values(self):
	return [value for group_values in self._iterations for value in group_values]

	def unit(self):
	return self._unit

	@staticmethod
	def metric_to_unit(metric):
	assert metric in ('Time', 'Malloc', 'JSHeap')
	return 'ms' if metric == 'Time' else 'bytes'

	@staticmethod
	def time_unit_to_metric(unit):
	return {'fps': 'FrameRate', 'runs/s': 'Runs', 'ms': 'Time'}[unit]


	class PerfTest(object):

	def __init__(self, port, test_name, test_path, test_runner_count=DEFAULT_TEST_RUNNER_COUNT):
	self._port = port
	self._test_name = test_name
	self._test_path = test_path
	self._description = None
	self._metrics = {}
	self._ordered_metrics_name = []
	self._test_runner_count = test_runner_count

	def test_name(self):
	return self._test_name

	def test_name_without_file_extension(self):
	return re.sub(r'\.\w+$', '', self.test_name())

	def test_path(self):
	return self._test_path

	def description(self):
	return self._description

	def prepare(self, time_out_ms):
	return True

	def _create_driver(self):
	return self._port.create_driver(worker_number=0, no_timeout=True)

	def run(self, time_out_ms):
	for _ in xrange(self._test_runner_count):
	driver = self._create_driver()
	try:
	if not self._run_with_driver(driver, time_out_ms):
	return None
	finally:
	driver.stop()

	should_log = not self._port.get_option('profile')
	if should_log and self._description:
	_log.info('DESCRIPTION: %s' % self._description)

	results = {}
	for metric_name in self._ordered_metrics_name:
	metric = self._metrics[metric_name]
	results[metric.name()] = metric.grouped_iteration_values()
	if should_log:
	legacy_chromium_bot_compatible_name = self.test_name_without_file_extension().replace('/', ': ')
	self.log_statistics(legacy_chromium_bot_compatible_name + ': ' + metric.name(),
	metric.flattened_iteration_values(), metric.unit())

	return results

	@staticmethod
	def log_statistics(test_name, values, unit):
	sorted_values = sorted(values)

	# Compute the mean and variance using Knuth's online algorithm (has good numerical stability).
	square_sum = 0
	mean = 0
	for i, time in enumerate(sorted_values):
	delta = time - mean
	sweep = i + 1.0
	mean += delta / sweep
	square_sum += delta * (time - mean)

	middle = int(len(sorted_values) / 2)
	mean = sum(sorted_values) / len(values)
	median = sorted_values[middle] if len(sorted_values) % 2 else (sorted_values[middle - 1] + sorted_values[middle]) / 2
	stdev = math.sqrt(square_sum / (len(sorted_values) - 1)) if len(sorted_values) > 1 else 0

	_log.info('RESULT %s= %s %s' % (test_name, mean, unit))
	_log.info('median= %s %s, stdev= %s %s, min= %s %s, max= %s %s' %
	(median, unit, stdev, unit, sorted_values[0], unit, sorted_values[-1], unit))

	_description_regex = re.compile(r'^Description: (?P<description>.*)$', re.IGNORECASE)
	_metrics_regex = re.compile(r'^(?P<metric>Time\|Malloc\|JS Heap):')
	_statistics_keys = ['avg', 'median', 'stdev', 'min', 'max', 'unit', 'values']
	_score_regex = re.compile(r'^(?P<key>' + r'\|'.join(_statistics_keys) + r')\s+(?P<value>([0-9\.]+(,\s+)?)+)\s(?P<unit>.)')
	_console_regex = re.compile(r'^CONSOLE (MESSAGE\|WARNING):')

	def _run_with_driver(self, driver, time_out_ms):
	output = self.run_single(driver, self.test_path(), time_out_ms)
	self._filter_output(output)
	if self.run_failed(output):
	return False

	current_metric = None
	for line in re.split('\n', output.text):
	description_match = self._description_regex.match(line)
	metric_match = self._metrics_regex.match(line)
	score = self._score_regex.match(line)
	console_match = self._console_regex.match(line)

	if description_match:
	self._description = description_match.group('description')
	elif metric_match:
	current_metric = metric_match.group('metric').replace(' ', '')
	elif score:
	if score.group('key') != 'values':
	continue

	metric = self._ensure_metrics(current_metric, score.group('unit'))
	metric.append_group(map(lambda value: float(value), score.group('value').split(', ')))
	elif console_match:
	# Ignore console messages such as deprecation warnings.
	continue
	else:
	_log.error('ERROR: ' + line)
	return False

	return True

	def _ensure_metrics(self, metric_name, unit=None):
	if metric_name not in self._metrics:
	self._metrics[metric_name] = PerfTestMetric(metric_name, unit)
	self._ordered_metrics_name.append(metric_name)
	return self._metrics[metric_name]

	def run_single(self, driver, test_path, time_out_ms, should_run_pixel_test=False):
	return driver.run_test(DriverInput(test_path, time_out_ms, image_hash=None, should_run_pixel_test=should_run_pixel_test, args=[]), stop_when_done=False)

	def run_failed(self, output):
	if output.error:
	_log.error('error: %s\n%s' % (self.test_name(), output.error))

	if output.text == None:
	pass
	elif output.timeout:
	_log.error('timeout: %s' % self.test_name())
	elif output.crash:
	_log.error('crash: %s' % self.test_name())
	else:
	return False

	return True

	@staticmethod
	def _should_ignore_line(regexps, line):
	if not line:
	return True
	for regexp in regexps:
	if regexp.search(line):
	return True
	return False

	_lines_to_ignore_in_stderr = [
	re.compile(r'^Unknown option:'),
	re.compile(r'^\[WARNING:proxy_service.cc'),
	re.compile(r'^\[INFO:'),
	# These stderr messages come from content_shell on Linux.
	re.compile(r'INFO:SkFontHost_fontconfig.cpp'),
	re.compile(r'Running without the SUID sandbox'),
	# crbug.com/345229
	re.compile(r'InitializeSandbox\(\) called with multiple threads in process gpu-process')]

	_lines_to_ignore_in_parser_result = [
	re.compile(r'^\s*Running \d+ times$'),
	re.compile(r'^\s*Ignoring warm-up '),
	re.compile(r'^\s*Info:'),
	re.compile(r'^\s\d+(.\d+)?(\s(runs\/s\|ms\|fps))?$'),
	# Following are for handle existing test like Dromaeo
	re.compile(re.escape("""main frame - has 1 onunload handler(s)""")),
	re.compile(re.escape("""frame "<!--framePath //<!--frame0-->-->" - has 1 onunload handler(s)""")),
	re.compile(re.escape("""frame "<!--framePath //<!--frame0-->/<!--frame0-->-->" - has 1 onunload handler(s)""")),
	# Following is for html5.html
	re.compile(re.escape("""Blocked access to external URL http://www.whatwg.org/specs/web-apps/current-work/""")),
	re.compile(r"CONSOLE MESSAGE: (line \d+: )?Blocked script execution in '[A-Za-z0-9\-\.:]+' because the document's frame is sandboxed and the 'allow-scripts' permission is not set."),
	re.compile(r"CONSOLE MESSAGE: (line \d+: )?Not allowed to load local resource"),
	# Dromaeo reports values for subtests. Ignore them for now.
	re.compile(r'(?P<name>.+): \[(?P<values>(\d+(.\d+)?,\s+)*\d+(.\d+)?)\]'),
	]

	def _filter_output(self, output):
	if output.error:
	output.error = '\n'.join([line for line in re.split('\n', output.error) if not self._should_ignore_line(self._lines_to_ignore_in_stderr, line)])
	if output.text:
	output.text = '\n'.join([line for line in re.split('\n', output.text) if not self._should_ignore_line(self._lines_to_ignore_in_parser_result, line)])


	class SingleProcessPerfTest(PerfTest):
	def __init__(self, port, test_name, test_path, test_runner_count=1):
	super(SingleProcessPerfTest, self).__init__(port, test_name, test_path, test_runner_count)


	class ChromiumStylePerfTest(PerfTest):
	_chromium_style_result_regex = re.compile(r'^RESULT\s+(?P<name>[^=]+)\s=\s+(?P<value>\d+(\.\d+)?)\s(?P<unit>\w+)$')

	def __init__(self, port, test_name, test_path, test_runner_count=DEFAULT_TEST_RUNNER_COUNT):
	super(ChromiumStylePerfTest, self).__init__(port, test_name, test_path, test_runner_count)

	def run(self, time_out_ms):
	driver = self._create_driver()
	try:
	output = self.run_single(driver, self.test_path(), time_out_ms)
	finally:
	driver.stop()

	self._filter_output(output)
	if self.run_failed(output):
	return None

	return self.parse_and_log_output(output)

	def parse_and_log_output(self, output):
	test_failed = False
	results = {}
	for line in re.split('\n', output.text):
	resultLine = ChromiumStylePerfTest._chromium_style_result_regex.match(line)
	if resultLine:
	# FIXME: Store the unit
	results[resultLine.group('name').replace(' ', '')] = float(resultLine.group('value'))
	_log.info(line)
	elif not len(line) == 0:
	test_failed = True
	_log.error(line)
	return results if results and not test_failed else None


	class PerfTestFactory(object):

	_pattern_map = [
	(re.compile(r'^Dromaeo/'), SingleProcessPerfTest),
	(re.compile(r'^inspector/'), ChromiumStylePerfTest),
	]

	@classmethod
	def create_perf_test(cls, port, test_name, path, test_runner_count=DEFAULT_TEST_RUNNER_COUNT):
	for (pattern, test_class) in cls._pattern_map:
	if pattern.match(test_name):
	return test_class(port, test_name, path, test_runner_count)
	return PerfTest(port, test_name, path, test_runner_count)