From 8e7be3aed109bbba4fd000413136449fe471b2ab Mon Sep 17 00:00:00 2001
From: Daniel Hiltgen <dhiltgen@users.noreply.github.com>
Date: Tue, 30 Jun 2026 10:49:55 -0700
Subject: [PATCH] ci: avoid unbounded parallelism (#16966)

build-darwin has gotten very slow in the past few releases, most likely due to unbounded parallelism in the MLX build causing the builder to thrash
---
 scripts/build_darwin.sh | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/scripts/build_darwin.sh b/scripts/build_darwin.sh
index 408285c7..d1187604 100755
--- a/scripts/build_darwin.sh
+++ b/scripts/build_darwin.sh
@@ -38,6 +38,11 @@ done
 shift $(( $OPTIND - 1 ))
 
 _build_darwin() {
+    BUILD_CPUS=$(getconf _NPROCESSORS_ONLN)
+    BUILD_JOBS=${OLLAMA_BUILD_PARALLEL:-$BUILD_CPUS}
+    BUILD_LOAD=${OLLAMA_BUILD_LOAD:-$BUILD_CPUS}
+    status "Build parallelism: $BUILD_JOBS, load limit: $BUILD_LOAD"
+
     SOURCE_BUILD=build/darwin-sources
     status "Preparing shared native sources"
     cmake -S . -B "$SOURCE_BUILD" -DOLLAMA_MLX_BACKENDS=metal_v3 -DOLLAMA_LLAMA_BACKENDS=
@@ -81,7 +86,7 @@ _build_darwin() {
             $MLX_EXTRA_ARGS
 
         GOOS=darwin GOARCH=$ARCH CGO_ENABLED=1 CGO_CFLAGS="$MLX_CGO_CFLAGS" CGO_LDFLAGS="$MLX_CGO_LDFLAGS" \
-            cmake --build "$BUILD_DIR" --target ollama-local --target ollama-mlx-backends --parallel
+            cmake --build "$BUILD_DIR" --target ollama-local --target ollama-mlx-backends --parallel "$BUILD_JOBS" -- -l "$BUILD_LOAD"
     done
 }