factorize cgroups detection (for proper jobs/load settings)

.ci/build_script.sh

@@ -12,19 +12,6 @@ fi
 mkdir -p "${CCACHE_DIR}"
 echo "using cache dir: ${CCACHE_DIR}"
 
-PROCS="$(getconf _NPROCESSORS_ONLN)"
-if [[ -r /sys/fs/cgroup/cpu/cpu.shares ]]; then
-    CG_PROCS=$(($(cat /sys/fs/cgroup/cpu/cpu.shares) / 1024))
-    echo "running under cgroups, allocated vs physical cores: ${CG_PROCS} / ${PROCS}"
-    PARALLEL_JOBS=$((CG_PROCS + (CG_PROCS + 1) / 2))
-    PARALLEL_LOAD="${PROCS}"
-else
-    PARALLEL_JOBS=$((PROCS + (PROCS + 1) / 2))
-    PARALLEL_LOAD="${PROCS}"
-fi
-echo "PARALLEL_JOBS: ${PARALLEL_JOBS}"
-echo "PARALLEL_LOAD: ${PARALLEL_LOAD}"
-
 travis_retry make fetchthirdparty TARGET=
 
 docker-make() {
@@ -43,15 +30,10 @@ docker-make() {
         /bin/bash -c "$(printf '%s && ' "${cmdlist[@]}")true"
 }
 
-makeargs=(
-    PARALLEL_JOBS="${PARALLEL_JOBS}"
-    PARALLEL_LOAD="${PARALLEL_LOAD}"
-    TARGET="${TARGET}"
-)
 if [[ -z "${DOCKER_IMG}" ]]; then
     './.ci/cache_restore_post.sh'
     trap './.ci/cache_save_pre.sh' EXIT
-    make "${makeargs[@]}" "$@"
+    make TARGET="${TARGET}" "$@"
 else
-    docker-make "${makeargs[@]}" VERBOSE=1 "$@"
+    docker-make TARGET="${TARGET}" VERBOSE=1 "$@"
 fi

.github/workflows/build.yml

@@ -90,9 +90,6 @@ jobs:
         id: build
         run: |
           export MACOSX_DEPLOYMENT_TARGET=11;
-          PROCS="$(getconf _NPROCESSORS_ONLN)"
-          export PARALLEL_JOBS="$((PROCS + (PROCS + 1) / 2))"
-          export PARALLEL_LOAD="${PROCS}"
           make fetchthirdparty && make
 
       - name: Build cache pre-save

Makefile.defs

@@ -3,10 +3,25 @@
 SHELL = env PATH='$(PATH)' bash
 
 ifeq (,$(PARALLEL_JOBS))
-  PARALLEL_JOBS := $(or $(patsubst -j%,%,$(filter -j%,$(MAKEFLAGS))),$(shell getconf _NPROCESSORS_ONLN))
+  PARALLEL_JOBS := $(or $(patsubst -j%,%,$(filter -j%,$(MAKEFLAGS))))
 endif
 ifeq (,$(PARALLEL_LOAD))
-  PARALLEL_LOAD := $(or $(patsubst -l%,%,$(filter -l%,$(MAKEFLAGS))),$(shell getconf _NPROCESSORS_ONLN))
+  PARALLEL_LOAD := $(or $(patsubst -l%,%,$(filter -l%,$(MAKEFLAGS))))
+endif
+ifeq (,$(and $(PARALLEL_JOBS),$(PARALLEL_LOAD)))
+  CORES := $(shell getconf _NPROCESSORS_ONLN)
+  ALLOCATED_CORES := $(CORES)
+  # Detect when running under cgroups, so we don't try
+  # to run with `make/ninja -j36 …` on some CI workers.
+  ifneq (,$(wildcard /sys/fs/cgroup/cpu/cpu.shares))
+    ALLOCATED_CORES := $(shell echo $$(($$(cat /sys/fs/cgroup/cpu/cpu.shares) / 1024)))
+  endif
+  ifeq (,$(PARALLEL_JOBS))
+    PARALLEL_JOBS := $(if $(CI),$(shell echo $$(($(ALLOCATED_CORES) + ($(ALLOCATED_CORES) + 1) / 2))),$(ALLOCATED_CORES))
+  endif
+  ifeq (,$(PARALLEL_LOAD))
+    PARALLEL_LOAD := $(CORES)
+  endif
 endif
 export PARALLEL_JOBS
 export PARALLEL_LOAD