From 3d385796da53b4f3036fdc392db890257f8a3c72 Mon Sep 17 00:00:00 2001
From: "J. Nick Koston" <nick@koston.org>
Date: Wed, 17 Jun 2020 15:23:42 -0500
Subject: [PATCH] Improve logbook performance when no entities are filtered
 (#36842)

Various tweaks to reduce the python overhead of
the lazy class
---
 homeassistant/components/logbook/__init__.py | 58 ++++++++++----------
 1 file changed, 28 insertions(+), 30 deletions(-)

diff --git a/homeassistant/components/logbook/__init__.py b/homeassistant/components/logbook/__init__.py
index 6309b7c970c..d970959ca39 100644
--- a/homeassistant/components/logbook/__init__.py
+++ b/homeassistant/components/logbook/__init__.py
@@ -377,7 +377,7 @@ def _get_events(hass, config, start_day, end_day, entity_id=None):
 
     def yield_events(query):
         """Yield Events that are not filtered away."""
-        for row in query.yield_per(500):
+        for row in query.yield_per(1000):
             event = LazyEventPartialState(row)
             if _keep_event(hass, event, entities_filter):
                 yield event
@@ -385,8 +385,10 @@ def _get_events(hass, config, start_day, end_day, entity_id=None):
     with session_scope(hass=hass) as session:
         if entity_id is not None:
             entity_ids = [entity_id.lower()]
-        else:
+        elif config.get(CONF_EXCLUDE) or config.get(CONF_INCLUDE):
             entity_ids = _get_related_entity_ids(session, entities_filter)
+        else:
+            entity_ids = None
 
         query = (
             session.query(
@@ -404,14 +406,21 @@ def _get_events(hass, config, start_day, end_day, entity_id=None):
                 Events.event_type.in_(ALL_EVENT_TYPES + list(hass.data.get(DOMAIN, {})))
             )
             .filter((Events.time_fired > start_day) & (Events.time_fired < end_day))
-            .filter(
+        )
+
+        if entity_ids:
+            query = query.filter(
                 (
                     (States.last_updated == States.last_changed)
                     & States.entity_id.in_(entity_ids)
                 )
                 | (States.state_id.is_(None))
             )
-        )
+        else:
+            query = query.filter(
+                (States.last_updated == States.last_changed)
+                | (States.state_id.is_(None))
+            )
 
         prev_states = {}
         return list(humanify(hass, yield_events(query), prev_states))
@@ -425,7 +434,6 @@ def _get_attribute(hass, entity_id, event, attribute):
 
 
 def _keep_event(hass, event, entities_filter):
-    entity_id = None
 
     if event.event_type == EVENT_STATE_CHANGED:
         entity_id = event.entity_id
@@ -444,20 +452,18 @@ def _keep_event(hass, event, entities_filter):
     elif event.event_type == EVENT_LOGBOOK_ENTRY:
         event_data = event.data
         domain = event_data.get(ATTR_DOMAIN)
-
+        entity_id = None
     elif event.event_type in hass.data.get(DOMAIN, {}) and not event.data.get(
         "entity_id"
     ):
         # If the entity_id isn't described, use the domain that describes
         # the event for filtering.
         domain = hass.data[DOMAIN][event.event_type][0]
-
+        entity_id = None
     else:
         event_data = event.data
         domain = event_data.get(ATTR_DOMAIN)
         entity_id = event_data.get("entity_id")
-        if entity_id:
-            domain = split_entity_id(entity_id)[0]
 
     if not entity_id and domain:
         entity_id = f"{domain}."
@@ -556,18 +562,25 @@ def _entry_message_from_event(hass, entity_id, domain, event):
 class LazyEventPartialState:
     """A lazy version of core Event with limited State joined in."""
 
-    __slots__ = ["_row", "_event_data", "_time_fired"]
+    __slots__ = [
+        "_row",
+        "_event_data",
+        "_time_fired",
+        "event_type",
+        "entity_id",
+        "state",
+        "domain",
+    ]
 
     def __init__(self, row):
         """Init the lazy event."""
         self._row = row
         self._event_data = None
         self._time_fired = None
-
-    @property
-    def event_type(self):
-        """Type of event."""
-        return self._row.event_type
+        self.event_type = self._row.event_type
+        self.entity_id = self._row.entity_id
+        self.state = self._row.state
+        self.domain = self._row.domain
 
     @property
     def context_user_id(self):
@@ -617,18 +630,3 @@ class LazyEventPartialState:
                 .get(ATTR_HIDDEN, False)
             )
         return False
-
-    @property
-    def entity_id(self):
-        """Entity id that changed state."""
-        return self._row.entity_id
-
-    @property
-    def domain(self):
-        """Domain of the entity_id that changed state."""
-        return self._row.domain
-
-    @property
-    def state(self):
-        """State of the entity_id that changed state."""
-        return self._row.state