Merge pull request #117016 from dims/set-GOMAXPROCS-explicitly

Set GOMAXPROCS explicitly

hack/lib/golang.sh

@@ -555,6 +555,19 @@ kube::golang::setup_env() {
 
   # This seems to matter to some tools
   export GO15VENDOREXPERIMENT=1
+
+  # GOMAXPROCS by default does not reflect the number of cpu(s) available
+  # when running in a container, please see https://github.com/golang/go/issues/33803
+  if ! command -v ncpu >/dev/null 2>&1; then
+    # shellcheck disable=SC2164
+    pushd "${KUBE_ROOT}/hack/tools" >/dev/null
+    GO111MODULE=on go install ./ncpu
+    # shellcheck disable=SC2164
+    popd >/dev/null
+  fi
+
+  GOMAXPROCS=${GOMAXPROCS:-$(ncpu)}
+  kube::log::status "Setting GOMAXPROCS: ${GOMAXPROCS}"
 }
 
 # This will take binaries from $GOPATH/bin and copy them to the appropriate

hack/tools/go.mod

@@ -9,6 +9,7 @@ require (
 	github.com/golang/mock v1.6.0
 	github.com/golangci/golangci-lint v1.51.2
 	github.com/google/go-flow-levee v0.1.5
+	go.uber.org/automaxprocs v1.5.2
 	gotest.tools/gotestsum v1.6.4
 	honnef.co/go/tools v0.4.2
 	sigs.k8s.io/logtools v0.4.1

hack/tools/go.sum

@@ -542,6 +542,7 @@ github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZN
 github.com/polyfloyd/go-errorlint v1.1.0 h1:VKoEFg5yxSgJ2yFPVhxW7oGz+f8/OVcuMeNvcPIi6Eg=
 github.com/polyfloyd/go-errorlint v1.1.0/go.mod h1:Uss7Bc/izYG0leCMRx3WVlrpqWedSZk7V/FUQW6VJ6U=
 github.com/posener/complete v1.1.1/go.mod h1:em0nMJCgc9GFtwrmVmEMR/ZL6WyhyjMBndrE9hABlRI=
+github.com/prashantv/gostub v1.1.0 h1:BTyx3RfQjRHnUWaGF9oQos79AlQ5k8WNktv7VGvVH4g=
 github.com/prometheus/client_golang v0.9.1/go.mod h1:7SWBe2y4D6OKWSNQJUaRYU/AaXPKyh/dDVn+NZz0KFw=
 github.com/prometheus/client_golang v0.9.3/go.mod h1:/TN21ttK/J9q6uSwhBd54HahCDft0ttaMvbicHlPoso=
 github.com/prometheus/client_golang v1.0.0/go.mod h1:db9x61etRT2tGnBNRi70OPL5FsnadC4Ky3P0J6CfImo=
@@ -718,6 +719,8 @@ go.opencensus.io v0.22.5/go.mod h1:5pWMHQbX5EPX2/62yrJeAkowc+lfs/XD7Uxpq3pI6kk=
 go.uber.org/atomic v1.4.0/go.mod h1:gD2HeocX3+yG+ygLZcrzQJaqmWj9AIm7n08wl/qW/PE=
 go.uber.org/atomic v1.7.0 h1:ADUqmZGgLDDfbSL9ZmPxKTybcoEYHgpYfELNoN+7hsw=
 go.uber.org/atomic v1.7.0/go.mod h1:fEN4uk6kAWBTFdckzkM89CLk9XfWZrxpCo0nPH17wJc=
+go.uber.org/automaxprocs v1.5.2 h1:2LxUOGiR3O6tw8ui5sZa2LAaHnsviZdVOUZw4fvbnME=
+go.uber.org/automaxprocs v1.5.2/go.mod h1:eRbA25aqJrxAbsLO0xy5jVwPt7FQnRgjW+efnwa1WM0=
 go.uber.org/multierr v1.1.0/go.mod h1:wR5kodmAFQ0UK8QlbwjlSNy0Z68gJhDJUG5sjR94q/0=
 go.uber.org/multierr v1.6.0 h1:y6IPFStTAIT5Ytl7/XYmHvzXQ7S3g/IeZW9hyZ5thw4=
 go.uber.org/multierr v1.6.0/go.mod h1:cdWPpRnG4AhwMwsgIHip0KRBQjJy5kYEpYjJxpXp9iU=

hack/tools/ncpu/main.go

@@ -0,0 +1,29 @@
+/*
+Copyright 2023 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package main
+
+import (
+	"fmt"
+	"runtime"
+
+	"go.uber.org/automaxprocs/maxprocs"
+)
+
+func main() {
+	maxprocs.Set()
+	fmt.Print(runtime.GOMAXPROCS(0))
+}

hack/tools/tools.go

@@ -36,4 +36,7 @@ import (
 
 	// mockgen
 	_ "github.com/golang/mock/mockgen"
+
+	// tools like cpu
+	_ "go.uber.org/automaxprocs"
 )