test write

fastwrite.go

@@ -0,0 +1,55 @@
+package main
+
+import (
+	"fmt"
+	"os"
+	"time"
+
+	"github.com/hanwen/go-fuse/v2/splice"
+)
+
+func copy(p *splice.Pair, f *os.File) (int64, error) {
+	total := int64(0)
+	for {
+		m, err := p.WriteTo(f.Fd(), 128<<10)
+		total += int64(m)
+		if err != nil {
+			return total, err
+		}
+	}
+}
+
+func main() {
+	if len(os.Args) < 2 {
+		fmt.Println("Usage: fastwrite <dst>")
+		return
+	}
+	dst := os.Args[1]
+	f, err := os.Create(dst)
+	if err != nil {
+		fmt.Println("Error:", err)
+		return
+	}
+	defer f.Close()
+
+	pair, _ := splice.Get()
+	pair.Grow(256 * 1024)
+	defer pair.Close()
+
+	go func() {
+		buf := make([]byte, 128<<10)
+		for i := 0; i < 1000; i++ {
+			pair.Write(buf)
+		}
+		pair.Close()
+	}()
+	start := time.Now()
+	copy(pair, f)
+	if err != nil {
+		fmt.Println("Error:", err)
+		return
+	}
+	used := time.Since(start)
+	speed := float64(128<<10*1000) / used.Seconds() / 1024 / 1024
+	fmt.Printf("Copied to %s in %v, speed: %.1f MiB/s\n", dst, used, speed)
+}