From 85faecb2fd27832583e3c3806a48383fc9601fe4 Mon Sep 17 00:00:00 2001
From: Jesse Hills <3060199+jesserockz@users.noreply.github.com>
Date: Thu, 27 Oct 2022 12:17:21 +1300
Subject: [PATCH] Add core config option to limit compile process count (#3952)

---
 esphome/const.py          | 1 +
 esphome/core/config.py    | 5 +++++
 esphome/platformio_api.py | 7 +++++--
 3 files changed, 11 insertions(+), 2 deletions(-)

diff --git a/esphome/const.py b/esphome/const.py
index fe76852f4c..56f48d2f92 100644
--- a/esphome/const.py
+++ b/esphome/const.py
@@ -116,6 +116,7 @@ CONF_COMMAND_RETAIN = "command_retain"
 CONF_COMMAND_TOPIC = "command_topic"
 CONF_COMMENT = "comment"
 CONF_COMMIT = "commit"
+CONF_COMPILE_PROCESS_LIMIT = "compile_process_limit"
 CONF_COMPONENT_ID = "component_id"
 CONF_COMPONENTS = "components"
 CONF_CONDITION = "condition"
diff --git a/esphome/core/config.py b/esphome/core/config.py
index 733cdcd66e..a40542c662 100644
--- a/esphome/core/config.py
+++ b/esphome/core/config.py
@@ -1,4 +1,5 @@
 import logging
+import multiprocessing
 import os
 import re
 
@@ -11,6 +12,7 @@ from esphome.const import (
     CONF_BOARD_FLASH_MODE,
     CONF_BUILD_PATH,
     CONF_COMMENT,
+    CONF_COMPILE_PROCESS_LIMIT,
     CONF_ESPHOME,
     CONF_FRAMEWORK,
     CONF_INCLUDES,
@@ -151,6 +153,9 @@ CONFIG_SCHEMA = cv.All(
             cv.Optional(CONF_MIN_VERSION, default=ESPHOME_VERSION): cv.All(
                 cv.version_number, validate_version
             ),
+            cv.Optional(CONF_COMPILE_PROCESS_LIMIT): cv.int_range(
+                min=1, max=multiprocessing.cpu_count()
+            ),
         }
     ),
     validate_hostname,
diff --git a/esphome/platformio_api.py b/esphome/platformio_api.py
index a4a3f32092..70576bec11 100644
--- a/esphome/platformio_api.py
+++ b/esphome/platformio_api.py
@@ -8,7 +8,7 @@ import os
 import re
 import subprocess
 
-from esphome.const import KEY_CORE
+from esphome.const import CONF_COMPILE_PROCESS_LIMIT, CONF_ESPHOME, KEY_CORE
 from esphome.core import CORE, EsphomeError
 from esphome.util import run_external_command, run_external_process
 
@@ -103,7 +103,10 @@ def run_platformio_cli_run(config, verbose, *args, **kwargs) -> Union[str, int]:
 
 
 def run_compile(config, verbose):
-    return run_platformio_cli_run(config, verbose)
+    args = []
+    if CONF_COMPILE_PROCESS_LIMIT in config[CONF_ESPHOME]:
+        args += [f"-j{config[CONF_ESPHOME][CONF_COMPILE_PROCESS_LIMIT]}"]
+    return run_platformio_cli_run(config, verbose, *args)
 
 
 def _run_idedata(config):