Add command line to benchmark DNS request and response with hot caches

1 files changed, 79 insertions, 0 deletions

diff --git a/cmd/resolverbench/main.go b/cmd/resolverbench/main.go
new file mode 100644
index 0000000..1e5e53b
--- /dev/null
+++ b/cmd/resolverbench/main.go
@@ -0,0 +1,79 @@
+package main
+
+import (
+	"bytes"
+	"fmt"
+	"log"
+	"os"
+
+	libdns "github.com/shuLhan/share/lib/dns"
+)
+
+func usage() {
+	fmt.Println("Usage: " + os.Args[0] + " <nameserver> <hosts-file>")
+	os.Exit(1)
+}
+
+func main() {
+	if len(os.Args) < 3 {
+		usage()
+	}
+
+	log.SetFlags(0)
+
+	cl, err := libdns.NewUDPClient(os.Args[1])
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	msgs, err := libdns.HostsLoad(os.Args[2])
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	var nfail int
+	res := libdns.AllocMessage()
+
+	fmt.Printf("= Benchmarking with %d messages\n", len(msgs))
+
+	for x := 0; x < len(msgs); x++ {
+		//fmt.Printf("< Request: %6d %s\n", x, msgs[x].Question)
+
+		_, err = cl.Send(msgs[x], cl.Addr)
+		if err != nil {
+			nfail++
+			log.Println("! Send error: ", err)
+			continue
+		}
+
+		res.Reset()
+
+		_, err = cl.Recv(res)
+		if err != nil {
+			nfail++
+			log.Println("! Recv error: ", err)
+			continue
+		}
+
+		err = res.UnmarshalBinary(res.Packet)
+		if err != nil {
+			nfail++
+			log.Println("! UnmarshalBinary:", err)
+			continue
+		}
+
+		exp := msgs[x].Answer[0].RData().([]byte)
+		got := res.Answer[0].RData().([]byte)
+
+		if !bytes.Equal(exp, got) {
+			nfail++
+			log.Printf(`! Answer not matched:
+expecting: %s
+got: %s
+`, exp, got)
+		}
+	}
+
+	fmt.Printf("= Total: %d\n", len(msgs))
+	fmt.Printf("= Failed: %d\n", nfail)
+}