Add antagonist processes to run_tests.py arsenal

These are processes consume CPU for the purpose of slowing down tests, allowing more timing related issues to be exposed.

tools/run_tests/antagonist.py

@@ -0,0 +1,34 @@
+#!/usr/bin/env python
+# Copyright 2015, Google Inc.
+# 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.
+
+"""This is used by run_tests.py to create cpu load on a machine"""
+
+while True:
+ pass

tools/run_tests/run_tests.py

@@ -40,6 +40,7 @@
 import sys
 import time
 import platform
+import subprocess
 
 import jobset
 import watch_dirs
@@ -350,6 +351,7 @@ def __str__(self):
  choices=sorted(_LANGUAGES.keys()),
  nargs='+',
  default=sorted(_LANGUAGES.keys()))
+argp.add_argument('-a', '--antagonists', default=0, type=int)
 args = argp.parse_args()
 
 # grab config
@@ -444,14 +446,21 @@ def _build_and_run(check_cancelled, newline_on_success, travis, cache):
  newline_on_success=newline_on_success, travis=travis):
  return 1
 
- # run all the tests
- all_runs = itertools.chain.from_iterable(
- itertools.repeat(one_run, runs_per_test))
- if not jobset.run(all_runs, check_cancelled,
- newline_on_success=newline_on_success, travis=travis,
- maxjobs=min(args.jobs, min(c.maxjobs for c in run_configs)),
- cache=cache):
- return 2
+ # start antagonists
+ antagonists = [subprocess.Popen(['tools/run_tests/antagonist.py']) 
+ for _ in range(0, args.antagonists)]
+ try:
+ # run all the tests
+ all_runs = itertools.chain.from_iterable(
+ itertools.repeat(one_run, runs_per_test))
+ if not jobset.run(all_runs, check_cancelled,
+ newline_on_success=newline_on_success, travis=travis,
+ maxjobs=min(args.jobs, min(c.maxjobs for c in run_configs)),
+ cache=cache):
+ return 2
+ finally:
+ for antagonist in antagonists:
+ antagonist.kill()
 
  return 0