From 8a41370950f951910c89f83089c3ce5285f3b845 Mon Sep 17 00:00:00 2001
From: "J. Nick Koston" <nick@koston.org>
Date: Thu, 5 May 2022 13:13:55 -0400
Subject: [PATCH] Add cache to split_entity_id (#71345)

---
 homeassistant/core.py | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/homeassistant/core.py b/homeassistant/core.py
index d6b1ac85d8b..b181e4c4106 100644
--- a/homeassistant/core.py
+++ b/homeassistant/core.py
@@ -133,9 +133,12 @@ SOURCE_YAML = ConfigSource.YAML.value
 # How long to wait until things that run on startup have to finish.
 TIMEOUT_EVENT_START = 15
 
+MAX_EXPECTED_ENTITY_IDS = 16384
+
 _LOGGER = logging.getLogger(__name__)
 
 
+@functools.lru_cache(MAX_EXPECTED_ENTITY_IDS)
 def split_entity_id(entity_id: str) -> tuple[str, str]:
     """Split a state entity ID into domain and object ID."""
     domain, _, object_id = entity_id.partition(".")