Change the default num_engine_workers to get_worker_count()

Now that we have decouple-nested merged, it makes sense
to enable more workers. oslo has a function just for this
processutils.get_worker_count()

Also set the number to 2 for functional tests to
not overly consume too much memory but still test
the multi worker path.

Change-Id: I86d1e8bb1813ccdee959f7a0fe78867dde7d21b5
Closes-bug: 1434339

heat/common/config.py

@@ -18,6 +18,7 @@ import logging as sys_logging
 import os
 
 from eventlet.green import socket
+from oslo_concurrency import processutils
 from oslo_config import cfg
 from oslo_log import log as logging
 
@@ -84,7 +85,7 @@ service_opts = [
                default=5,
                help=_('Maximum depth allowed when using nested stacks.')),
     cfg.IntOpt('num_engine_workers',
-               default=1,
+               default=processutils.get_worker_count(),
                help=_('Number of heat-engine processes to fork and run.'))]
 
 engine_opts = [

heat_integrationtests/pre_test_hook.sh

@@ -17,4 +17,6 @@
 localrc_path=$BASE/new/devstack/localrc
 localconf=$BASE/new/devstack/local.conf
 echo "HEAT_ENABLE_ADOPT_ABANDON=True" >> $localrc_path
-echo -e '[[post-config|$HEAT_CONF]]\n[DEFAULT]\nnotification_driver=messagingv2' >> $localconf
+echo -e '[[post-config|$HEAT_CONF]]\n[DEFAULT]\n' >> $localconf
+echo -e 'notification_driver=messagingv2\n' >> $localconf
+echo -e 'num_engine_workers=2\n' >> $localconf

requirements.txt

@@ -13,6 +13,7 @@ kombu>=2.5.0
 lxml>=2.3
 netaddr>=0.7.12
 oslo.config>=1.9.3,<1.10.0  # Apache-2.0
+oslo.concurrency>=1.8.0,<1.9.0         # Apache-2.0
 oslo.context>=0.2.0,<0.3.0                     # Apache-2.0
 oslo.db>=1.7.0,<1.8.0  # Apache-2.0
 oslo.i18n>=1.5.0,<1.6.0  # Apache-2.0