deb-mistral/mistral/tests/unit/engine/test_lookup_utils.py
Renat Akhmerov 086a3d43fa Fix memory leak related to cached lookups
* It turned out that Mistral used a lot of memory because it
  used cached DB lookups for task executions (only task executions
  in a terminal state get cached) and the maximum size of the cache
  was too big, 20000 entries. One task execution in certain cases
  may take a lot of memory (e.g. several megabytes) so 20000 objects
  make memory footprint huge. Additionally, when a workflow completes
  we need to invalidate coresponding task executions in the cache.
  This didn't happen before this patch.
* This patch fixes the aforementioned issues by using partial
  invalidation of the cache and setting smaller cache size.
* Fixed "Starting workflow .." log statement to not print the entire
  structure of the workflow definition into the workflow log, only its
  name and input parameters
* Minor style fixes

Change-Id: I0ee300f631a4bdfa2f618c2a10048267f27b3345
Closes-bug: #1664864
2017-02-17 19:23:39 +07:00

83 lines
2.7 KiB
Python

# Copyright 2017 - Nokia Networks.
#
# 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.
from oslo_config import cfg
from mistral.db.v2 import api as db_api
from mistral.services import workflows as wf_service
from mistral.tests.unit.engine import base
from mistral.workflow import lookup_utils
from mistral.workflow import states
# Use the set_default method to set value otherwise in certain test cases
# the change in value is not permanent.
cfg.CONF.set_default('auth_enable', False, group='pecan')
class LookupUtilsTest(base.EngineTestCase):
def test_task_execution_cache_invalidation(self):
wf_text = """---
version: '2.0'
wf:
tasks:
task1:
action: std.noop
on-success: join_task
task2:
action: std.noop
on-success: join_task
join_task:
join: all
on-success: task4
task4:
action: std.noop
pause-before: true
"""
wf_service.create_workflows(wf_text)
# Start workflow.
wf_ex = self.engine.start_workflow('wf', {})
self.await_workflow_paused(wf_ex.id)
with db_api.transaction():
# Note: We need to reread execution to access related tasks.
wf_ex = db_api.get_workflow_execution(wf_ex.id)
tasks = wf_ex.task_executions
self.assertEqual(4, len(tasks))
self._assert_single_item(tasks, name='task1', state=states.SUCCESS)
self._assert_single_item(tasks, name='task2', state=states.SUCCESS)
self._assert_single_item(tasks, name='join_task', state=states.SUCCESS)
self._assert_single_item(tasks, name='task4', state=states.IDLE)
# Expecting one cache entry because we know that 'join' operation
# uses cached lookups and the workflow is not finished yet.
self.assertEqual(1, lookup_utils.get_task_execution_cache_size())
self.engine.resume_workflow(wf_ex.id)
self.await_workflow_success(wf_ex.id)
# Expecting that the cache size is 0 because the workflow has
# finished and invalidated corresponding cache entry.
self.assertEqual(0, lookup_utils.get_task_execution_cache_size())