Apply conservative database connection reduction changes (#14066)

This is expected to free up 4 additional database connections per traditional node
  compare to roughly 12 in total before this change

Out of these 3 are accomplished by using existing connection for recently added services
  then 1 is obtained by closing the connection for the idle callback receiver main process

Signed-off-by: jessicamack <jmack@redhat.com>
Co-authored-by: jessicamack <jmack@redhat.com>

awx/main/dispatch/worker/base.py

@@ -143,9 +143,10 @@ class AWXConsumerRedis(AWXConsumerBase):
     def run(self, *args, **kwargs):
         super(AWXConsumerRedis, self).run(*args, **kwargs)
         self.worker.on_start()
+        logger.info(f'Callback receiver started with pid={os.getpid()}')
+        db.connection.close()  # logs use database, so close connection
 
         while True:
-            logger.debug(f'{os.getpid()} is alive')
             time.sleep(60)
 
 

awx/main/management/commands/run_cache_clear.py

@@ -2,6 +2,7 @@ import logging
 import json
 
 from django.core.management.base import BaseCommand
+
 from awx.main.dispatch import pg_bus_conn
 from awx.main.dispatch.worker.task import TaskWorker
 
@@ -18,7 +19,7 @@ class Command(BaseCommand):
 
     def handle(self, *arg, **options):
         try:
-            with pg_bus_conn(new_connection=True) as conn:
+            with pg_bus_conn() as conn:
                 conn.listen("tower_settings_change")
                 for e in conn.events(yield_timeouts=True):
                     if e is not None:

awx/main/management/commands/run_rsyslog_configurer.py

@@ -22,7 +22,7 @@ class Command(BaseCommand):
 
     def handle(self, *arg, **options):
         try:
-            with pg_bus_conn(new_connection=True) as conn:
+            with pg_bus_conn() as conn:
                 conn.listen("rsyslog_configurer")
                 # reconfigure rsyslog on start up
                 reconfigure_rsyslog()

awx/main/management/commands/run_ws_heartbeat.py

@@ -30,11 +30,11 @@ class Command(BaseCommand):
         sys.exit(0)
 
     def do_hearbeat_loop(self):
-        with pg_bus_conn(new_connection=True) as conn:
+        while True:
-            while True:
+            with pg_bus_conn() as conn:
                 logger.debug('Sending heartbeat')
                 conn.notify('web_ws_heartbeat', self.construct_payload())
-                time.sleep(settings.BROADCAST_WEBSOCKET_BEACON_FROM_WEB_RATE_SECONDS)
+            time.sleep(settings.BROADCAST_WEBSOCKET_BEACON_FROM_WEB_RATE_SECONDS)
 
     def handle(self, *arg, **options):
         signal.signal(signal.SIGTERM, self.notify_listener_and_exit)