From e1296737a69703535a3688f2dd205821f0e9d073 Mon Sep 17 00:00:00 2001
From: Mark Felder <feld@feld.me>
Date: Sun, 22 Sep 2024 15:19:05 -0400
Subject: [PATCH] Disable busywaits in releases

---
 changelog.d/release-tuning.change | 1 +
 rel/vm.args.eex                   | 5 +++++
 2 files changed, 6 insertions(+)
 create mode 100644 changelog.d/release-tuning.change

diff --git a/changelog.d/release-tuning.change b/changelog.d/release-tuning.change
new file mode 100644
index 000000000..bf9abc3ad
--- /dev/null
+++ b/changelog.d/release-tuning.change
@@ -0,0 +1 @@
+Tuning for release builds to lower CPU usage.
diff --git a/rel/vm.args.eex b/rel/vm.args.eex
index 71e803264..8e38fee4b 100644
--- a/rel/vm.args.eex
+++ b/rel/vm.args.eex
@@ -9,3 +9,8 @@
 
 ## Tweak GC to run more often
 ##-env ERL_FULLSWEEP_AFTER 10
+
+# Disable wasteful busywait.
++sbwt none
++sbwtdcpu none
++sbwtdio none