From 46c1b6eaee4ca00c256c5c403c6d6bfeaf3b63f8 Mon Sep 17 00:00:00 2001 From: Johannes Erdfelt Date: Sun, 25 Mar 2012 02:06:01 +0800 Subject: Add multi-process support for API services Implements blueprint multi-process-api-service This is based on Huang Zhiteng's patch. This patch adds support for running services as multiple processes. This is primarily intended to be used with the API service as a way to provide more concurrency than eventlet can sometimes provide. A SIGTERM or SIGINT signal will cause the parent process to gracefully terminate the child processes, allowing them to finish processing the requests currently being processed. The parent will wait for the children to finish before exiting. Change-Id: Ie6d6802626eb42d5e64c4167be363fbf6cea2a1b --- nova/tests/__init__.py | 2 +- nova/tests/integrated/test_multiprocess_api.py | 169 +++++++++++++++++++++++++ nova/tests/test_service.py | 6 +- nova/tests/test_wsgi.py | 4 +- 4 files changed, 173 insertions(+), 8 deletions(-) create mode 100644 nova/tests/integrated/test_multiprocess_api.py (limited to 'nova/tests') diff --git a/nova/tests/__init__.py b/nova/tests/__init__.py index dff2ad649..9ff38e3a9 100644 --- a/nova/tests/__init__.py +++ b/nova/tests/__init__.py @@ -44,7 +44,7 @@ from nova import log as logging import eventlet -eventlet.monkey_patch() +eventlet.monkey_patch(os=False) FLAGS = flags.FLAGS FLAGS.use_stderr = False diff --git a/nova/tests/integrated/test_multiprocess_api.py b/nova/tests/integrated/test_multiprocess_api.py new file mode 100644 index 000000000..6fe1479cd --- /dev/null +++ b/nova/tests/integrated/test_multiprocess_api.py @@ -0,0 +1,169 @@ +# Copyright (c) 2012 Intel, LLC +# Copyright (c) 2012 OpenStack, LLC +# +# Licensed under the Apache License, Version 2.0 (the "License"); you may +# not use this file except in compliance with the License. You may obtain +# a copy of the License at +# +# http://www.apache.org/licenses/LICENSE-2.0 +# +# Unless required by applicable law or agreed to in writing, software +# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT +# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the +# License for the specific language governing permissions and limitations +# under the License. + +""" +Test multiprocess enabled API service. +""" +import os +import signal +import time +import traceback + +from nova import flags +from nova.log import logging +from nova import service +from nova.tests.integrated import integrated_helpers + +FLAGS = flags.FLAGS +LOG = logging.getLogger(__name__) + + +class MultiprocessWSGITest(integrated_helpers._IntegratedTestBase): + def _start_api_service(self): + # Process will be started in _spawn() + self.osapi = service.WSGIService("osapi_compute") + self.auth_url = 'http://%s:%s/v2' % (self.osapi.host, self.osapi.port) + LOG.info('auth_url = %s' % self.auth_url) + + def _get_flags(self): + self.workers = 2 + f = super(MultiprocessWSGITest, self)._get_flags() + f['osapi_compute_workers'] = self.workers + return f + + def _spawn(self): + pid = os.fork() + if pid == 0: + # NOTE(johannes): We can't let the child processes exit back + # into the unit test framework since then we'll have multiple + # processes running the same tests (and possibly forking more + # processes that end up in the same situation). So we need + # to catch all exceptions and make sure nothing leaks out, in + # particlar SystemExit, which is raised by sys.exit(). We use + # os._exit() which doesn't have this problem. + status = 0 + try: + launcher = service.ProcessLauncher() + launcher.launch_server(self.osapi, workers=self.osapi.workers) + launcher.wait() + except SystemExit as exc: + status = exc.code + except BaseException: + # We need to be defensive here too + try: + traceback.print_exc() + except BaseException: + print "Couldn't print traceback" + status = 2 + + # Really exit + os._exit(status) + + self.pid = pid + + # Wait for up to a second for workers to get started + start = time.time() + while time.time() - start < 1: + workers = self._get_workers() + if len(workers) == self.workers: + break + + time.sleep(.1) + + self.assertEqual(len(workers), self.workers) + return workers + + def tearDown(self): + if self.pid: + # Make sure all processes are stopped + os.kill(self.pid, signal.SIGTERM) + + # Make sure we reap our test process + self._reap_test() + + super(MultiprocessWSGITest, self).tearDown() + + def _reap_test(self): + pid, status = os.waitpid(self.pid, 0) + self.pid = None + return status + + def _get_workers(self): + f = os.popen('ps ax -o pid,ppid,command') + # Skip ps header + f.readline() + + processes = [tuple(int(p) for p in l.strip().split()[:2]) + for l in f.readlines()] + return [p for p, pp in processes if pp == self.pid] + + def test_killed_worker_recover(self): + start_workers = self._spawn() + + # kill one worker and check if new worker can come up + LOG.info('pid of first child is %s' % start_workers[0]) + os.kill(start_workers[0], signal.SIGTERM) + + # loop and check if new worker is spawned (for 1 second max) + start = time.time() + while time.time() - start < 1: + end_workers = self._get_workers() + LOG.info('workers: %r' % end_workers) + + if start_workers != end_workers: + break + + time.sleep(.1) + + # Make sure worker pids don't match + self.assertNotEqual(start_workers, end_workers) + + # check if api service still works + flavors = self.api.get_flavors() + self.assertTrue(len(flavors) > 0, 'Num of flavors > 0.') + + def _terminate_with_signal(self, sig): + self._spawn() + + # check if api service is working + flavors = self.api.get_flavors() + self.assertTrue(len(flavors) > 0, 'Num of flavors > 0.') + + os.kill(self.pid, sig) + + # loop and check if all processes are killed (for 1 second max) + start = time.time() + while time.time() - start < 1: + workers = self._get_workers() + LOG.info('workers: %r' % workers) + + if not workers: + break + + time.sleep(.1) + + self.assertFalse(workers, 'No OS processes left.') + + def test_terminate_sigkill(self): + self._terminate_with_signal(signal.SIGKILL) + status = self._reap_test() + self.assertTrue(os.WIFSIGNALED(status)) + self.assertEqual(os.WTERMSIG(status), signal.SIGKILL) + + def test_terminate_sigterm(self): + self._terminate_with_signal(signal.SIGTERM) + status = self._reap_test() + self.assertTrue(os.WIFEXITED(status)) + self.assertEqual(os.WEXITSTATUS(status), 0) diff --git a/nova/tests/test_service.py b/nova/tests/test_service.py index 2b6c83653..6aa390a11 100644 --- a/nova/tests/test_service.py +++ b/nova/tests/test_service.py @@ -40,7 +40,7 @@ test_service_opts = [ default="nova.tests.test_service.FakeManager", help="Manager for testing"), cfg.StrOpt("test_service_listen", - default=None, + default='127.0.0.1', help="Host to bind test service to"), cfg.IntOpt("test_service_listen_port", default=0, @@ -202,7 +202,6 @@ class TestWSGIService(test.TestCase): def test_service_random_port(self): test_service = service.WSGIService("test_service") - self.assertEquals(0, test_service.port) test_service.start() self.assertNotEqual(0, test_service.port) test_service.stop() @@ -216,10 +215,7 @@ class TestLauncher(test.TestCase): self.service = service.WSGIService("test_service") def test_launch_app(self): - self.assertEquals(0, self.service.port) launcher = service.Launcher() launcher.launch_server(self.service) - # Give spawned thread a chance to execute - greenthread.sleep(0) self.assertNotEquals(0, self.service.port) launcher.stop() diff --git a/nova/tests/test_wsgi.py b/nova/tests/test_wsgi.py index 20b2bf81e..9f694f4bc 100644 --- a/nova/tests/test_wsgi.py +++ b/nova/tests/test_wsgi.py @@ -84,8 +84,8 @@ class TestWSGIServer(unittest.TestCase): self.assertEquals("test_app", server.name) def test_start_random_port(self): - server = nova.wsgi.Server("test_random_port", None, host="127.0.0.1") - self.assertEqual(0, server.port) + server = nova.wsgi.Server("test_random_port", None, + host="127.0.0.1", port=0) server.start() self.assertNotEqual(0, server.port) server.stop() -- cgit