WIP: Benchmark typical vcs read operations.

shurcooL · Aug 11, 2017 · 5b25b3f · 5b25b3f
1 parent 2a944ce
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diff --git a/229/main.go b/229/main.go
@@ -0,0 +1,193 @@
+package main
+
+import (
+	"crypto/sha256"
+	"fmt"
+	"io"
+	"log"
+	"net/http"
+	"path"
+	"time"
+
+	"github.com/dustin/go-humanize"
+
+	"sourcegraph.com/sourcegraph/go-vcs/vcs"
+	"sourcegraph.com/sourcegraph/go-vcs/vcs/gitcmd"
+
+	"github.com/shurcooL/play/229/vcs/git"
+)
+
+func main() {
+	const dir = "/src/net/http"
+	//const dir = "/src/encoding"
+
+	{
+		err := runDisk(dir)
+		if err != nil {
+			log.Fatalln(err)
+		}
+	}
+	// net/http: read total: 16.042893ms 1.2 MB (1182569 bytes) 3fcc1476bde7246ce53e3fbc5a71cd9ec0e4cbead3a7ed941385f4dd2742dd7e
+
+	if false {
+		gitcmd.SetModTime = true
+		err := runGit(dir)
+		if err != nil {
+			log.Fatalln(err)
+		}
+	}
+	// net/http: read total: 10.837731283s 1.2 MB (1182569 bytes) 3fcc1476bde7246ce53e3fbc5a71cd9ec0e4cbead3a7ed941385f4dd2742dd7e
+
+	if false {
+		gitcmd.SetModTime = false
+		err := runGit(dir)
+		if err != nil {
+			log.Fatalln(err)
+		}
+	}
+	// read total: 2.885154088s 1.2 MB (1182569 bytes) 3fcc1476bde7246ce53e3fbc5a71cd9ec0e4cbead3a7ed941385f4dd2742dd7e
+
+	{
+		err := runNewGit(dir)
+		if err != nil {
+			log.Fatalln(err)
+		}
+	}
+	// net/http: ?
+}
+
+func runDisk(dir string) error {
+	t := time.Now()
+	fs := http.Dir("/usr/local/go")
+	f, err := fs.Open(dir)
+	if err != nil {
+		return err
+	}
+	defer func() {
+		err := f.Close()
+		if err != nil {
+			log.Println(err)
+		}
+	}()
+	fis, err := f.Readdir(0)
+	if err != nil {
+		return err
+	}
+	var (
+		total uint64 // Bytes.
+		h     = sha256.New()
+	)
+	for _, fi := range fis {
+		if fi.IsDir() {
+			continue
+		}
+		f, err := fs.Open(path.Join(dir, fi.Name()))
+		if err != nil {
+			return err
+		}
+		n, err := io.Copy(h, f)
+		if err != nil {
+			f.Close()
+			return err
+		}
+		err = f.Close()
+		if err != nil {
+			return err
+		}
+		total += uint64(n)
+	}
+	fmt.Printf("%v: read total: %v %v (%v bytes) %x\n", dir[5:], time.Since(t), humanize.Bytes(total), total, h.Sum(nil))
+	return nil
+}
+
+func runGit(dir string) error {
+	t := time.Now()
+	r, err := vcs.Open("git", "/tmp/try/vcs-store/git/https/go.googlesource.com/go")
+	if err != nil {
+		return err
+	}
+	fs, err := r.FileSystem("go1.9rc2")
+	if err != nil {
+		return err
+	}
+	fis, err := fs.ReadDir(dir)
+	if err != nil {
+		return err
+	}
+	var (
+		total uint64 // Bytes.
+		h     = sha256.New()
+	)
+	for _, fi := range fis {
+		if fi.IsDir() {
+			continue
+		}
+		f, err := fs.Open(path.Join(dir, fi.Name()))
+		if err != nil {
+			return err
+		}
+		n, err := io.Copy(h, f)
+		if err != nil {
+			f.Close()
+			return err
+		}
+		err = f.Close()
+		if err != nil {
+			return err
+		}
+		total += uint64(n)
+	}
+	fmt.Printf("%v: read total: %v %v (%v bytes) %x\n", dir[5:], time.Since(t), humanize.Bytes(total), total, h.Sum(nil))
+	return nil
+}
+
+func runNewGit(dir string) error {
+	t := time.Now()
+	r, err := git.Open("/tmp/try/vcs-store/git/https/go.googlesource.com/go")
+	if err != nil {
+		return err
+	}
+	fs, err := r.FileSystem("go1.9rc2")
+	if err != nil {
+		return err
+	}
+	f, err := fs.Open(dir)
+	if err != nil {
+		return err
+	}
+	defer func() {
+		err := f.Close()
+		if err != nil {
+			log.Println(err)
+		}
+	}()
+	fis, err := f.Readdir(0)
+	if err != nil {
+		return err
+	}
+	var (
+		total uint64 // Bytes.
+		h     = sha256.New()
+	)
+	for _, fi := range fis {
+		if fi.IsDir() {
+			continue
+		}
+		f, err := fs.Open(path.Join(dir, fi.Name()))
+		if err != nil {
+			return err
+		}
+		n, err := io.Copy(h, f)
+		if err != nil {
+			f.Close()
+			return err
+		}
+		err = f.Close()
+		if err != nil {
+			return err
+		}
+		total += uint64(n)
+	}
+	fmt.Printf("%v: read total: %v %v (%v bytes) %x\n", dir[5:], time.Since(t), humanize.Bytes(total), total, h.Sum(nil))
+	return nil
+}