feat: Set the number of worker threads to start

assets/runtime/config/master.yml

@@ -25,6 +25,15 @@ cachedir: {{SALT_CACHE_DIR}}/master
 extension_modules: {{SALT_CACHE_DIR}}/master/extmods
 
 
+#####  Large-scale tuning settings   #####
+##########################################
+# The number of worker threads to start. These threads are used to manage
+# return calls made from minions to the master. If the master seems to be
+# running slowly, increase the number of threads. This setting can not be
+# set lower than 3.
+worker_threads: {{SALT_WORKER_THREADS}}
+
+
 #####        Security settings       #####
 ##########################################
 # Enable passphrase protection of the Master signing_key. This only applies if