Moving result reading to a background thread

lib/ansible/executor/action_write_locks.py

@@ -0,0 +1,43 @@
+# (c) 2016 - Red Hat, Inc. <support@ansible.com>
+#
+# This file is part of Ansible
+#
+# Ansible is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# Ansible is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with Ansible.  If not, see <http://www.gnu.org/licenses/>.
+
+# Make coding more python3-ish
+from __future__ import (absolute_import, division, print_function)
+__metaclass__ = type
+
+from multiprocessing import Lock
+from ansible.module_utils.facts import Facts
+
+if 'action_write_locks' not in globals():
+    # Do not initialize this more than once because it seems to bash
+    # the existing one.  multiprocessing must be reloading the module
+    # when it forks?
+    action_write_locks = dict()
+
+    # Below is a Lock for use when we weren't expecting a named module.
+    # It gets used when an action plugin directly invokes a module instead
+    # of going through the strategies.  Slightly less efficient as all
+    # processes with unexpected module names will wait on this lock
+    action_write_locks[None] = Lock()
+
+    # These plugins are called directly by action plugins (not going through
+    # a strategy).  We precreate them here as an optimization
+    mods = set(p['name'] for p in Facts.PKG_MGRS)
+    mods.update(('copy', 'file', 'setup', 'slurp', 'stat'))
+    for mod_name in mods:
+        action_write_locks[mod_name] = Lock()
+

lib/ansible/executor/module_common.py

@@ -36,7 +36,7 @@ from ansible.module_utils._text import to_bytes, to_text
 # Must import strategy and use write_locks from there
 # If we import write_locks directly then we end up binding a
 # variable to the object and then it never gets updated.
-from ansible.plugins import strategy
+from ansible.executor import action_write_locks
 
 try:
     from __main__ import display
@@ -605,16 +605,16 @@ def _find_snippet_imports(module_name, module_data, module_path, module_args, ta
             display.debug('ANSIBALLZ: using cached module: %s' % cached_module_filename)
             zipdata = open(cached_module_filename, 'rb').read()
         else:
-            if module_name in strategy.action_write_locks:
+            if module_name in action_write_locks.action_write_locks:
                 display.debug('ANSIBALLZ: Using lock for %s' % module_name)
-                lock = strategy.action_write_locks[module_name]
+                lock = action_write_locks.action_write_locks[module_name]
             else:
                 # If the action plugin directly invokes the module (instead of
                 # going through a strategy) then we don't have a cross-process
                 # Lock specifically for this module.  Use the "unexpected
                 # module" lock instead
                 display.debug('ANSIBALLZ: Using generic lock for %s' % module_name)
-                lock = strategy.action_write_locks[None]
+                lock = action_write_locks.action_write_locks[None]
 
             display.debug('ANSIBALLZ: Acquiring lock')
             with lock:

lib/ansible/executor/task_queue_manager.py

@@ -285,6 +285,7 @@ class TaskQueueManager:
         for host_name in iterator.get_failed_hosts():
             self._failed_hosts[host_name] = True
 
+        strategy.cleanup()
         self._cleanup_processes()
         return play_return
 

lib/ansible/playbook/conditional.py

@@ -25,6 +25,7 @@ from ansible.compat.six import text_type
 from ansible.errors import AnsibleError, AnsibleUndefinedVariable
 from ansible.playbook.attribute import FieldAttribute
 from ansible.template import Templar
+from ansible.module_utils._text import to_native
 
 class Conditional:
 
@@ -72,7 +73,7 @@ class Conditional:
                 if not self._check_conditional(conditional, templar, all_vars):
                     return False
         except Exception as e:
-            raise AnsibleError("The conditional check '%s' failed. The error was: %s" % (conditional, e), obj=ds)
+            raise AnsibleError("The conditional check '%s' failed. The error was: %s" % (to_native(conditional), to_native(e)), obj=ds)
 
         return True
 

lib/ansible/plugins/strategy/__init__.py

@@ -19,14 +19,18 @@
 from __future__ import (absolute_import, division, print_function)
 __metaclass__ = type
 
+import os
+import threading
 import time
 
+from collections import deque
 from multiprocessing import Lock
 from jinja2.exceptions import UndefinedError
 
 from ansible.compat.six.moves import queue as Queue
 from ansible.compat.six import iteritems, string_types
 from ansible.errors import AnsibleError, AnsibleParserError, AnsibleUndefinedVariable
+from ansible.executor import action_write_locks
 from ansible.executor.process.worker import WorkerProcess
 from ansible.executor.task_result import TaskResult
 from ansible.inventory.host import Host
@@ -50,25 +54,6 @@ except ImportError:
 
 __all__ = ['StrategyBase']
 
-if 'action_write_locks' not in globals():
-    # Do not initialize this more than once because it seems to bash
-    # the existing one.  multiprocessing must be reloading the module
-    # when it forks?
-    action_write_locks = dict()
-
-    # Below is a Lock for use when we weren't expecting a named module.
-    # It gets used when an action plugin directly invokes a module instead
-    # of going through the strategies.  Slightly less efficient as all
-    # processes with unexpected module names will wait on this lock
-    action_write_locks[None] = Lock()
-
-    # These plugins are called directly by action plugins (not going through
-    # a strategy).  We precreate them here as an optimization
-    mods = set(p['name'] for p in Facts.PKG_MGRS)
-    mods.update(('copy', 'file', 'setup', 'slurp', 'stat'))
-    for mod_name in mods:
-        action_write_locks[mod_name] = Lock()
-
 # TODO: this should probably be in the plugins/__init__.py, with
 #       a smarter mechanism to set all of the attributes based on
 #       the loaders created there
@@ -86,6 +71,25 @@ class SharedPluginLoaderObj:
         self.module_loader = module_loader
 
 
+_sentinel = object()
+def results_thread_main(strategy):
+    #print("RESULT THREAD STARTING: %s" % threading.current_thread())
+    while True:
+        try:
+            result = strategy._final_q.get()
+            if type(result) == object:
+                break
+            else:
+                #print("result in thread is: %s" % result._result)
+                strategy._results_lock.acquire()
+                strategy._results.append(result)
+                strategy._results_lock.release()
+        except (IOError, EOFError):
+            break
+        except Queue.Empty:
+            pass
+    #print("RESULT THREAD EXITED: %s" % threading.current_thread())
+
 class StrategyBase:
 
     '''
@@ -104,6 +108,7 @@ class StrategyBase:
         self._final_q           = tqm._final_q
         self._step              = getattr(tqm._options, 'step', False)
         self._diff              = getattr(tqm._options, 'diff', False)
+
         # Backwards compat: self._display isn't really needed, just import the global display and use that.
         self._display           = display
 
@@ -115,6 +120,18 @@ class StrategyBase:
         # outstanding tasks still in queue
         self._blocked_hosts     = dict()
 
+        self._results = deque()
+        self._results_lock = threading.Condition(threading.Lock())
+
+        #print("creating thread for strategy %s" % id(self))
+        self._results_thread = threading.Thread(target=results_thread_main, args=(self,))
+        self._results_thread.daemon = True
+        self._results_thread.start()
+
+    def cleanup(self):
+        self._final_q.put(_sentinel)
+        self._results_thread.join()
+
     def run(self, iterator, play_context, result=0):
         # save the failed/unreachable hosts, as the run_handlers()
         # method will clear that information during its execution
@@ -174,10 +191,9 @@ class StrategyBase:
         # tasks inside of play_iterator so we'd have to extract them to do it
         # there.
 
-        global action_write_locks
+        if task.action not in action_write_locks.action_write_locks:
-        if task.action not in action_write_locks:
             display.debug('Creating lock for %s' % task.action)
-            action_write_locks[task.action] = Lock()
+            action_write_locks.action_write_locks[task.action] = Lock()
 
         # and then queue the new task
         try:
@@ -211,7 +227,7 @@ class StrategyBase:
             return
         display.debug("exiting _queue_task() for %s/%s" % (host.name, task.action))
 
-    def _process_pending_results(self, iterator, one_pass=False):
+    def _process_pending_results(self, iterator, one_pass=False, max_passes=None):
         '''
         Reads results off the final queue and takes appropriate action
         based on the result (executing callbacks, updating state, etc.).
@@ -270,10 +286,16 @@ class StrategyBase:
             else:
                 return False
 
-        passes = 0
+        cur_pass = 0
-        while not self._tqm._terminated:
+        while True:
             try:
-                task_result = self._final_q.get(timeout=0.001)
+                self._results_lock.acquire()
+                task_result = self._results.pop()
+            except IndexError:
+                break
+            finally:
+                self._results_lock.release()
+
             original_host = get_original_host(task_result._host)
             original_task = iterator.get_original_task(original_host, task_result._task)
             task_result._host = original_host
@@ -296,6 +318,7 @@ class StrategyBase:
                 continue
 
             if original_task.register:
+                #print("^ REGISTERING RESULT %s" % original_task.register)
                 if original_task.run_once:
                     host_list = [host for host in self._inventory.get_hosts(iterator._play.hosts) if host.name not in self._tqm._unreachable_hosts]
                 else:
@@ -484,13 +507,10 @@ class StrategyBase:
 
             ret_results.append(task_result)
 
-            except Queue.Empty:
+            if one_pass or max_passes is not None and (cur_pass+1) >= max_passes:
-                passes += 1
-                if passes > 2:
                 break
 
-            if one_pass:
+            cur_pass += 1
-                break
 
         return ret_results
 

lib/ansible/plugins/strategy/linear.py

@@ -263,16 +263,14 @@ class StrategyModule(StrategyBase):
                     if run_once:
                         break
 
-                    # FIXME: probably not required here any more with the result proc
+                    results += self._process_pending_results(iterator, max_passes=max(1, int(len(self._tqm._workers) * 0.1)))
-                    #        having been removed, so there's no only a single result
-                    #        queue for the main thread
-                    results += self._process_pending_results(iterator, one_pass=True)
 
                 # go to next host/task group
                 if skip_rest:
                     continue
 
                 display.debug("done queuing things up, now waiting for results queue to drain")
+                if self._pending_results > 0:
                     results += self._wait_on_pending_results(iterator)
                 host_results.extend(results)
 

test/units/plugins/strategies/test_strategy_base.py

@@ -45,16 +45,49 @@ class TestStrategyBase(unittest.TestCase):
         pass
 
     def test_strategy_base_init(self):
+        queue_items = []
+        def _queue_empty(*args, **kwargs):
+            return len(queue_items) == 0
+        def _queue_get(*args, **kwargs):
+            if len(queue_items) == 0:
+                raise Queue.Empty
+            else:
+                return queue_items.pop()
+        def _queue_put(item, *args, **kwargs):
+            queue_items.append(item)
+
+        mock_queue = MagicMock()
+        mock_queue.empty.side_effect = _queue_empty
+        mock_queue.get.side_effect = _queue_get
+        mock_queue.put.side_effect = _queue_put
+
         mock_tqm = MagicMock(TaskQueueManager)
-        mock_tqm._final_q = MagicMock()
+        mock_tqm._final_q = mock_queue
         mock_tqm._options = MagicMock()
         mock_tqm._notified_handlers = {}
         mock_tqm._listening_handlers = {}
         strategy_base = StrategyBase(tqm=mock_tqm)
+        strategy_base.cleanup()
 
     def test_strategy_base_run(self):
+        queue_items = []
+        def _queue_empty(*args, **kwargs):
+            return len(queue_items) == 0
+        def _queue_get(*args, **kwargs):
+            if len(queue_items) == 0:
+                raise Queue.Empty
+            else:
+                return queue_items.pop()
+        def _queue_put(item, *args, **kwargs):
+            queue_items.append(item)
+
+        mock_queue = MagicMock()
+        mock_queue.empty.side_effect = _queue_empty
+        mock_queue.get.side_effect = _queue_get
+        mock_queue.put.side_effect = _queue_put
+
         mock_tqm = MagicMock(TaskQueueManager)
-        mock_tqm._final_q = MagicMock()
+        mock_tqm._final_q = mock_queue
         mock_tqm._stats = MagicMock()
         mock_tqm._notified_handlers = {}
         mock_tqm._listening_handlers = {}
@@ -87,8 +120,25 @@ class TestStrategyBase(unittest.TestCase):
         mock_tqm._unreachable_hosts = dict(host1=True)
         mock_iterator.get_failed_hosts.return_value = []
         self.assertEqual(strategy_base.run(iterator=mock_iterator, play_context=mock_play_context, result=False), mock_tqm.RUN_UNREACHABLE_HOSTS)
+        strategy_base.cleanup()
 
     def test_strategy_base_get_hosts(self):
+        queue_items = []
+        def _queue_empty(*args, **kwargs):
+            return len(queue_items) == 0
+        def _queue_get(*args, **kwargs):
+            if len(queue_items) == 0:
+                raise Queue.Empty
+            else:
+                return queue_items.pop()
+        def _queue_put(item, *args, **kwargs):
+            queue_items.append(item)
+
+        mock_queue = MagicMock()
+        mock_queue.empty.side_effect = _queue_empty
+        mock_queue.get.side_effect = _queue_get
+        mock_queue.put.side_effect = _queue_put
+
         mock_hosts = []
         for i in range(0, 5):
             mock_host = MagicMock()
@@ -100,7 +150,7 @@ class TestStrategyBase(unittest.TestCase):
         mock_inventory.get_hosts.return_value = mock_hosts
 
         mock_tqm = MagicMock()
-        mock_tqm._final_q = MagicMock()
+        mock_tqm._final_q = mock_queue
         mock_tqm._notified_handlers = {}
         mock_tqm._listening_handlers = {}
         mock_tqm.get_inventory.return_value = mock_inventory
@@ -120,6 +170,7 @@ class TestStrategyBase(unittest.TestCase):
 
         mock_tqm._unreachable_hosts = ["host02"]
         self.assertEqual(strategy_base.get_hosts_remaining(play=mock_play), mock_hosts[2:])
+        strategy_base.cleanup()
 
     @patch.object(WorkerProcess, 'run')
     def test_strategy_base_queue_task(self, mock_worker):
@@ -178,10 +229,13 @@ class TestStrategyBase(unittest.TestCase):
                 raise Queue.Empty
             else:
                 return queue_items.pop()
+        def _queue_put(item, *args, **kwargs):
+            queue_items.append(item)
 
         mock_queue = MagicMock()
         mock_queue.empty.side_effect = _queue_empty
         mock_queue.get.side_effect = _queue_get
+        mock_queue.put.side_effect = _queue_put
         mock_tqm._final_q = mock_queue
 
         mock_tqm._stats = MagicMock()
@@ -272,7 +326,7 @@ class TestStrategyBase(unittest.TestCase):
         strategy_base._blocked_hosts['test01'] = True
         strategy_base._pending_results = 1
         mock_iterator.is_failed.return_value = True
-        results = strategy_base._process_pending_results(iterator=mock_iterator)
+        results = strategy_base._wait_on_pending_results(iterator=mock_iterator)
         self.assertEqual(len(results), 1)
         self.assertEqual(results[0], task_result)
         self.assertEqual(strategy_base._pending_results, 0)
@@ -306,7 +360,7 @@ class TestStrategyBase(unittest.TestCase):
         queue_items.append(TaskResult(host=mock_host.name, task=mock_task._uuid, return_data=dict(add_host=dict(host_name='newhost01', new_groups=['foo']))))
         strategy_base._blocked_hosts['test01'] = True
         strategy_base._pending_results = 1
-        results = strategy_base._process_pending_results(iterator=mock_iterator)
+        results = strategy_base._wait_on_pending_results(iterator=mock_iterator)
         self.assertEqual(len(results), 1)
         self.assertEqual(strategy_base._pending_results, 0)
         self.assertNotIn('test01', strategy_base._blocked_hosts)
@@ -314,7 +368,7 @@ class TestStrategyBase(unittest.TestCase):
         queue_items.append(TaskResult(host=mock_host.name, task=mock_task._uuid, return_data=dict(add_group=dict(group_name='foo'))))
         strategy_base._blocked_hosts['test01'] = True
         strategy_base._pending_results = 1
-        results = strategy_base._process_pending_results(iterator=mock_iterator)
+        results = strategy_base._wait_on_pending_results(iterator=mock_iterator)
         self.assertEqual(len(results), 1)
         self.assertEqual(strategy_base._pending_results, 0)
         self.assertNotIn('test01', strategy_base._blocked_hosts)
@@ -322,7 +376,7 @@ class TestStrategyBase(unittest.TestCase):
         queue_items.append(TaskResult(host=mock_host.name, task=mock_task._uuid, return_data=dict(changed=True, _ansible_notify=['test handler'])))
         strategy_base._blocked_hosts['test01'] = True
         strategy_base._pending_results = 1
-        results = strategy_base._process_pending_results(iterator=mock_iterator)
+        results = strategy_base._wait_on_pending_results(iterator=mock_iterator)
         self.assertEqual(len(results), 1)
         self.assertEqual(strategy_base._pending_results, 0)
         self.assertNotIn('test01', strategy_base._blocked_hosts)
@@ -341,6 +395,7 @@ class TestStrategyBase(unittest.TestCase):
 
         #queue_items.append(('bad'))
         #self.assertRaises(AnsibleError, strategy_base._process_pending_results, iterator=mock_iterator)
+        strategy_base.cleanup()
 
     def test_strategy_base_load_included_file(self):
         fake_loader = DictDataLoader({
@@ -351,13 +406,30 @@ class TestStrategyBase(unittest.TestCase):
             """,
         })
 
+        queue_items = []
+        def _queue_empty(*args, **kwargs):
+            return len(queue_items) == 0
+        def _queue_get(*args, **kwargs):
+            if len(queue_items) == 0:
+                raise Queue.Empty
+            else:
+                return queue_items.pop()
+        def _queue_put(item, *args, **kwargs):
+            queue_items.append(item)
+
+        mock_queue = MagicMock()
+        mock_queue.empty.side_effect = _queue_empty
+        mock_queue.get.side_effect = _queue_get
+        mock_queue.put.side_effect = _queue_put
+
         mock_tqm = MagicMock()
-        mock_tqm._final_q = MagicMock()
+        mock_tqm._final_q = mock_queue
         mock_tqm._notified_handlers = {}
         mock_tqm._listening_handlers = {}
 
         strategy_base = StrategyBase(tqm=mock_tqm)
         strategy_base._loader = fake_loader
+        strategy_base.cleanup()
 
         mock_play = MagicMock()
 
@@ -443,4 +515,5 @@ class TestStrategyBase(unittest.TestCase):
 
             result = strategy_base.run_handlers(iterator=mock_iterator, play_context=mock_play_context)
         finally:
+            strategy_base.cleanup()
             tqm.cleanup()