Etcdctl: benchmark for hashkv performance

The benchmark as a sub command of put when provided will fetch hashkv and checks
the time taken to get it.

Fixed # 8910

Provider a way to etcd user to check how long it takes to get
hashkv in user enviornment. The command ouput will provide time taken
to get hashkv along with db file size.

tools/benchmark/cmd/put.go

@@ -21,6 +21,8 @@ import (
 	"math"
 	"math/rand"
 	"os"
+	"strconv"
+	"strings"
 	"time"
 
 	v3 "github.com/coreos/etcd/clientv3"
@@ -51,6 +53,8 @@ var (
 
 	compactInterval   time.Duration
 	compactIndexDelta int64
+
+	checkHashkv bool
 )
 
 func init() {
@@ -64,6 +68,7 @@ func init() {
 	putCmd.Flags().BoolVar(&seqKeys, "sequential-keys", false, "Use sequential keys")
 	putCmd.Flags().DurationVar(&compactInterval, "compact-interval", 0, `Interval to compact database (do not duplicate this with etcd's 'auto-compaction-retention' flag) (e.g. --compact-interval=5m compacts every 5-minute)`)
 	putCmd.Flags().Int64Var(&compactIndexDelta, "compact-index-delta", 1000, "Delta between current revision and compact revision (e.g. current revision 10000, compact at 9000)")
+	putCmd.Flags().BoolVar(&checkHashkv, "check-hashkv", false, "Check hashkv")
 }
 
 func putFunc(cmd *cobra.Command, args []string) {
@@ -126,6 +131,11 @@ func putFunc(cmd *cobra.Command, args []string) {
 	close(r.Results())
 	bar.Finish()
 	fmt.Println(<-rc)
+
+	// Check hashkv
+	if checkHashkv {
+		hashKV(cmd, clients)
+	}
 }
 
 func compactKV(clients []*v3.Client) {
@@ -150,3 +160,40 @@ func max(n1, n2 int64) int64 {
 	}
 	return n2
 }
+
+func hashKV(cmd *cobra.Command, clients []*v3.Client) {
+	var epHashKVRev int64
+	eps, err := cmd.Flags().GetStringSlice("endpoints")
+	if err != nil {
+		panic(err)
+	}
+	for i, ip := range eps {
+		eps[i] = strings.TrimSpace(ip)
+	}
+	st := time.Now()
+	var results string
+	ctx, cancel := context.WithCancel(context.Background())
+	clients[0].HashKV(ctx, eps[0], epHashKVRev)
+	host := eps[0]
+
+	resphash, errhash := clients[0].HashKV(ctx, host, epHashKVRev)
+	respstatus, errstatus := clients[0].Status(ctx, host)
+	cancel()
+	if errhash != nil {
+		fmt.Fprintf(os.Stderr, "Failed to get the hashkv of endpoint %s (%v)\n", host, errhash)
+		panic(err)
+	}
+	results += fmt.Sprintf("\nHaskKV Summary:\n")
+	results += fmt.Sprintf("  HashKV: %v \t\n", resphash.Hash)
+	results += fmt.Sprintf("  Endpoint: %v \t\n", host)
+	results += fmt.Sprintf("  Time taken to get hashkv: %v \t\n", time.Since(st).String())
+
+	// Get the db size
+	if errstatus != nil {
+		fmt.Println(fmt.Fprintf(os.Stderr, "Failed to get the status of endpoint %s (%v)\n", host, errstatus))
+		panic(err)
+	}
+	dbsize := float64(respstatus.DbSize) / (1000 * 1000 * 1000)
+	results += fmt.Sprintf("  DB size: %vGB \t\n", strconv.FormatFloat(dbsize, 'f', 2, 64))
+	fmt.Println(results)
+}