cmd/go: add benchmark for go list -m

Updates #63136

src/cmd/go/list_test.go

@@ -0,0 +1,190 @@
+// Copyright 2024 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main_test
+
+import (
+	"internal/testenv"
+	"io"
+	"net/http"
+	"os"
+	"path/filepath"
+	"strings"
+	"sync/atomic"
+	"testing"
+)
+
+var modulesForTest = []struct {
+	name                string
+	testDataFolder      string
+	url                 string
+	dependenciesToStrip []string
+}{
+	{
+		name:           "Empty",
+		testDataFolder: "empty",
+	},
+	{
+		name:           "Cmd",
+		testDataFolder: "cmd",
+	},
+	{
+		name:           "K8S",
+		testDataFolder: "k8s",
+		url:            "https://raw.githubusercontent.com/kubernetes/kubernetes/b33ef18bdfa62d3975f2c72743373f1d69740b99",
+		dependenciesToStrip: []string{
+			"k8s.io/api",
+			"k8s.io/apiextensions-apiserver",
+			"k8s.io/apimachinery",
+			"k8s.io/apiserver",
+			"k8s.io/cli-runtime",
+			"k8s.io/client-go",
+			"k8s.io/cloud-provider",
+			"k8s.io/cluster-bootstrap",
+			"k8s.io/code-generator",
+			"k8s.io/component-base",
+			"k8s.io/component-helpers",
+			"k8s.io/controller-manager",
+			"k8s.io/cri-api",
+			"k8s.io/cri-client",
+			"k8s.io/csi-translation-lib",
+			"k8s.io/dynamic-resource-allocation",
+			"k8s.io/endpointslice",
+			"k8s.io/kms",
+			"k8s.io/kube-aggregator",
+			"k8s.io/kube-controller-manager",
+			"k8s.io/kube-proxy",
+			"k8s.io/kube-scheduler",
+			"k8s.io/kubectl",
+			"k8s.io/kubelet",
+			"k8s.io/metrics",
+			"k8s.io/mount-utils",
+			"k8s.io/pod-security-admission",
+			"k8s.io/sample-apiserver",
+			"k8s.io/sample-cli-plugin",
+			"k8s.io/sample-controller",
+		},
+	},
+}
+
+func BenchmarkListModules(b *testing.B) {
+	testenv.MustHaveExec(b)
+	gotool, err := testenv.GoTool()
+	if err != nil {
+		b.Fatal(err)
+	}
+
+	tempDir := b.TempDir()
+	if err := prepareTestModules(tempDir); err != nil {
+		b.Fatal(err)
+	}
+
+	b.ResetTimer()
+	for _, m := range modulesForTest {
+		// Do not run in parallel. GOPROXY rate limits may affect parallel executions.
+		b.Run(m.name, func(b *testing.B) {
+			// We collect extra metrics.
+			var n, userTime, systemTime int64
+			modDir := filepath.Join(tempDir, m.testDataFolder, "go.mod")
+			for i := 0; i < b.N; i++ {
+				cmd := testenv.Command(b, gotool, "list", "-m", "-modfile="+modDir, "-mod=readonly", "all")
+
+				// Guarantees clean module cache for every execution.
+				gopath := b.TempDir()
+				cmd.Env = append(cmd.Env, "GOPATH="+gopath)
+
+				if err := cmd.Run(); err != nil {
+					b.Fatal(err)
+				}
+				atomic.AddInt64(&n, 1)
+				atomic.AddInt64(&userTime, int64(cmd.ProcessState.UserTime()))
+				atomic.AddInt64(&systemTime, int64(cmd.ProcessState.SystemTime()))
+
+			}
+			b.ReportMetric(float64(userTime)/float64(n), "user-ns/op")
+			b.ReportMetric(float64(systemTime)/float64(n), "sys-ns/op")
+		})
+	}
+}
+
+func prepareTestModules(tempDir string) error {
+	err := os.CopyFS(tempDir, os.DirFS(filepath.Join("testdata", "list")))
+	if err != nil {
+		return err
+	}
+	for _, m := range modulesForTest {
+		if m.url != "" {
+			modulePath := filepath.Join(tempDir, m.testDataFolder)
+			if err := downloadModule(modulePath, m.url, m.dependenciesToStrip); err != nil {
+				return err
+			}
+		}
+	}
+	return nil
+}
+
+func downloadModule(modulePath string, url string, dependenciesToStrip []string) error {
+
+	if err := os.Mkdir(modulePath, 0755); err != nil {
+		return err
+	}
+	sumText, err := fetchText(url + "/go.sum")
+	if err != nil {
+		return err
+	}
+
+	if err := writeFile(filepath.Join(modulePath, "go.sum"), sumText); err != nil {
+		return err
+	}
+
+	modText, err := fetchText(url + "/go.mod")
+	if err != nil {
+		return err
+	}
+
+	strippedModText := stripDependencies(modText, dependenciesToStrip)
+
+	return writeFile(filepath.Join(modulePath, "go.mod"), strippedModText)
+}
+
+func stripDependencies(goModText string, dependenciesToStrip []string) string {
+	var filteredLines []string
+	lines := strings.Split(goModText, "\n")
+	for _, line := range lines {
+		if !containsAny(line, dependenciesToStrip) {
+			filteredLines = append(filteredLines, line)
+		}
+	}
+	filteredText := strings.Join(filteredLines, "\n")
+	return filteredText
+}
+
+func containsAny(text string, options []string) bool {
+	for _, option := range options {
+		if strings.Contains(text, option) {
+			return true
+		}
+	}
+	return false
+}
+
+func writeFile(filePath, content string) error {
+	out, err := os.Create(filePath)
+	if err != nil {
+		return err
+	}
+	defer out.Close()
+	_, err = io.WriteString(out, content)
+	return err
+}
+
+func fetchText(url string) (string, error) {
+	resp, err := http.Get(url)
+	if err != nil {
+		return "", err
+	}
+	defer resp.Body.Close()
+	body, err := io.ReadAll(resp.Body)
+	return string(body), err
+}

src/cmd/go/testdata/list/cmd/go.mod

@@ -0,0 +1,15 @@
+module cmd
+
+go 1.22
+
+require (
+	github.com/google/pprof v0.0.0-20230811205829-9131a7e9cc17
+	golang.org/x/arch v0.6.0
+	golang.org/x/mod v0.14.0
+	golang.org/x/sync v0.5.0
+	golang.org/x/sys v0.15.0
+	golang.org/x/term v0.15.0
+	golang.org/x/tools v0.16.2-0.20231218185909-83bceaf2424d
+)
+
+require github.com/ianlancetaylor/demangle v0.0.0-20230524184225-eabc099b10ab // indirect

src/cmd/go/testdata/list/cmd/go.sum

@@ -0,0 +1,16 @@
+github.com/google/pprof v0.0.0-20230811205829-9131a7e9cc17 h1:0h35ESZ02+hN/MFZb7XZOXg+Rl9+Rk8fBIf5YLws9gA=
+github.com/google/pprof v0.0.0-20230811205829-9131a7e9cc17/go.mod h1:Jh3hGz2jkYak8qXPD19ryItVnUgpgeqzdkY/D0EaeuA=
+github.com/ianlancetaylor/demangle v0.0.0-20230524184225-eabc099b10ab h1:BA4a7pe6ZTd9F8kXETBoijjFJ/ntaa//1wiH9BZu4zU=
+github.com/ianlancetaylor/demangle v0.0.0-20230524184225-eabc099b10ab/go.mod h1:gx7rwoVhcfuVKG5uya9Hs3Sxj7EIvldVofAWIUtGouw=
+golang.org/x/arch v0.6.0 h1:S0JTfE48HbRj80+4tbvZDYsJ3tGv6BUU3XxyZ7CirAc=
+golang.org/x/arch v0.6.0/go.mod h1:FEVrYAQjsQXMVJ1nsMoVVXPZg6p2JE2mx8psSWTDQys=
+golang.org/x/mod v0.14.0 h1:dGoOF9QVLYng8IHTm7BAyWqCqSheQ5pYWGhzW00YJr0=
+golang.org/x/mod v0.14.0/go.mod h1:hTbmBsO62+eylJbnUtE2MGJUyE7QWk4xUqPFrRgJ+7c=
+golang.org/x/sync v0.5.0 h1:60k92dhOjHxJkrqnwsfl8KuaHbn/5dl0lUPUklKo3qE=
+golang.org/x/sync v0.5.0/go.mod h1:Czt+wKu1gCyEFDUtn0jG5QVvpJ6rzVqr5aXyt9drQfk=
+golang.org/x/sys v0.15.0 h1:h48lPFYpsTvQJZF4EKyI4aLHaev3CxivZmv7yZig9pc=
+golang.org/x/sys v0.15.0/go.mod h1:/VUhepiaJMQUp4+oa/7Zr1D23ma6VTLIYjOOTFZPUcA=
+golang.org/x/term v0.15.0 h1:y/Oo/a/q3IXu26lQgl04j/gjuBDOBlx7X6Om1j2CPW4=
+golang.org/x/term v0.15.0/go.mod h1:BDl952bC7+uMoWR75FIrCDx79TPU9oHkTZ9yRbYOrX0=
+golang.org/x/tools v0.16.2-0.20231218185909-83bceaf2424d h1:9YOyUBubvYqtjjtZBnI62JT9/QB9jfPwOQ7xLeyuOIU=
+golang.org/x/tools v0.16.2-0.20231218185909-83bceaf2424d/go.mod h1:kYVVN6I1mBNoB1OX+noeBjbRk4IUEPa7JJ+TJMEooJ0=

src/cmd/go/testdata/list/empty/go.mod

@@ -0,0 +1,3 @@
+module empty
+
+go 1.22