diff --git a/weed/command/volume.go b/weed/command/volume.go
index 58dee0e52..cbd5bc676 100644
--- a/weed/command/volume.go
+++ b/weed/command/volume.go
@@ -258,7 +258,7 @@ func (v VolumeServerOptions) startVolumeServer(volumeFolders, maxVolumeCounts, v
 		v.folders, v.folderMaxLimits, minFreeSpaces, diskTypes,
 		*v.idxFolder,
 		volumeNeedleMapKind,
-		v.masters, constants.VolumePulseSeconds, *v.dataCenter, *v.rack,
+		v.masters, constants.VolumePulsePeriod, *v.dataCenter, *v.rack,
 		v.whiteList,
 		*v.fixJpgOrientation, *v.readMode,
 		*v.compactionMBPerSecond,
diff --git a/weed/server/constants/volume.go b/weed/server/constants/volume.go
index 77c7b7b47..a1287d118 100644
--- a/weed/server/constants/volume.go
+++ b/weed/server/constants/volume.go
@@ -1,5 +1,7 @@
 package constants
 
+import "time"
+
 const (
-	VolumePulseSeconds = 5
+	VolumePulsePeriod = 5 * time.Second
 )
diff --git a/weed/server/volume_grpc_client_to_master.go b/weed/server/volume_grpc_client_to_master.go
index 2abde1bd9..9c2f8b213 100644
--- a/weed/server/volume_grpc_client_to_master.go
+++ b/weed/server/volume_grpc_client_to_master.go
@@ -68,7 +68,7 @@ func (vs *VolumeServer) heartbeat() {
 				master = newLeader
 			}
 			vs.store.MasterAddress = master
-			newLeader, err = vs.doHeartbeatWithRetry(master, grpcDialOption, time.Duration(vs.pulseSeconds)*time.Second, duplicateRetryCount)
+			newLeader, err = vs.doHeartbeatWithRetry(master, grpcDialOption, vs.pulsePeriod, duplicateRetryCount)
 			if err != nil {
 				glog.V(0).Infof("heartbeat to %s error: %v", master, err)
 
@@ -81,7 +81,7 @@ func (vs *VolumeServer) heartbeat() {
 				} else {
 					// Regular error, reset duplicate retry count
 					duplicateRetryCount = 0
-					time.Sleep(time.Duration(vs.pulseSeconds) * time.Second)
+					time.Sleep(vs.pulsePeriod)
 				}
 
 				newLeader = ""
diff --git a/weed/server/volume_server.go b/weed/server/volume_server.go
index 66c62b98c..4f8a7fb0d 100644
--- a/weed/server/volume_server.go
+++ b/weed/server/volume_server.go
@@ -35,7 +35,7 @@ type VolumeServer struct {
 	SeedMasterNodes []pb.ServerAddress
 	whiteList       []string
 	currentMaster   pb.ServerAddress
-	pulseSeconds    int
+	pulsePeriod     time.Duration
 	dataCenter      string
 	rack            string
 	store           *storage.Store
@@ -59,7 +59,7 @@ func NewVolumeServer(adminMux, publicMux *http.ServeMux, ip string,
 	folders []string, maxCounts []int32, minFreeSpaces []util.MinFreeSpace, diskTypes []types.DiskType,
 	idxFolder string,
 	needleMapKind storage.NeedleMapKind,
-	masterNodes []pb.ServerAddress, pulseSeconds int,
+	masterNodes []pb.ServerAddress, pulsePeriod time.Duration,
 	dataCenter string, rack string,
 	whiteList []string,
 	fixJpgOrientation bool,
@@ -86,7 +86,7 @@ func NewVolumeServer(adminMux, publicMux *http.ServeMux, ip string,
 	readExpiresAfterSec := v.GetInt("jwt.signing.read.expires_after_seconds")
 
 	vs := &VolumeServer{
-		pulseSeconds:                  pulseSeconds,
+		pulsePeriod:                   pulsePeriod,
 		dataCenter:                    dataCenter,
 		rack:                          rack,
 		needleMapKind:                 needleMapKind,
diff --git a/weed/shell/command_volume_check_disk.go b/weed/shell/command_volume_check_disk.go
index a8cc72d4d..741df0dd4 100644
--- a/weed/shell/command_volume_check_disk.go
+++ b/weed/shell/command_volume_check_disk.go
@@ -88,7 +88,8 @@ func (c *commandVolumeCheckDisk) eqVolumeFileCount(a, b *VolumeReplica) (bool, b
 	return fileCountA == fileCountB, fileDeletedCountA == fileDeletedCountB
 }
 
-func (c *commandVolumeCheckDisk) shouldSkipVolume(a, b *VolumeReplica, pulseTimeAtSecond int64, syncDeletions, verbose bool) bool {
+func (c *commandVolumeCheckDisk) shouldSkipVolume(a, b *VolumeReplica, pulseTime time.Time, syncDeletions, verbose bool) bool {
+	pulseTimeAtSecond := pulseTime.Unix()
 	doSyncDeletedCount := false
 	if syncDeletions && a.info.DeleteCount != b.info.DeleteCount {
 		doSyncDeletedCount = true
@@ -135,7 +136,7 @@ func (c *commandVolumeCheckDisk) Do(args []string, commandEnv *CommandEnv, write
 	c.writer = writer
 
 	// collect topology information
-	pulseTimeAtSecond := time.Now().Unix() - constants.VolumePulseSeconds*2
+	pulseTime := time.Now().Add(-constants.VolumePulsePeriod * 2)
 	topologyInfo, _, err := collectTopologyInfo(commandEnv, 0)
 	if err != nil {
 		return err
@@ -162,7 +163,7 @@ func (c *commandVolumeCheckDisk) Do(args []string, commandEnv *CommandEnv, write
 		})
 		for len(writableReplicas) >= 2 {
 			a, b := writableReplicas[0], writableReplicas[1]
-			if !*slowMode && c.shouldSkipVolume(a, b, pulseTimeAtSecond, *syncDeletions, *verbose) {
+			if !*slowMode && c.shouldSkipVolume(a, b, pulseTime, *syncDeletions, *verbose) {
 				// always choose the larger volume to be the source
 				writableReplicas = append(replicas[:1], writableReplicas[2:]...)
 				continue
diff --git a/weed/shell/command_volume_check_disk_test.go b/weed/shell/command_volume_check_disk_test.go
index ab9832bd4..d86b40f1f 100644
--- a/weed/shell/command_volume_check_disk_test.go
+++ b/weed/shell/command_volume_check_disk_test.go
@@ -1,9 +1,11 @@
 package shell
 
 import (
-	"github.com/seaweedfs/seaweedfs/weed/pb/master_pb"
 	"os"
 	"testing"
+	"time"
+
+	"github.com/seaweedfs/seaweedfs/weed/pb/master_pb"
 )
 
 type testCommandVolumeCheckDisk struct {
@@ -65,7 +67,8 @@ func TestShouldSkipVolume(t *testing.T) {
 		},
 	}
 	for num, tt := range tests {
-		if isShould := cmdVolumeCheckDisk.shouldSkipVolume(&tt.a, &tt.b, tt.pulseTimeAtSecond, true, true); isShould != tt.shouldSkipVolume {
+		pulseTime := time.Unix(tt.pulseTimeAtSecond, 0)
+		if isShould := cmdVolumeCheckDisk.shouldSkipVolume(&tt.a, &tt.b, pulseTime, true, true); isShould != tt.shouldSkipVolume {
 			t.Fatalf("result of should skip volume is unexpected for %d test", num)
 		}
 	}
diff --git a/weed/topology/volume_growth.go b/weed/topology/volume_growth.go
index 2a71c6e23..5442ccdce 100644
--- a/weed/topology/volume_growth.go
+++ b/weed/topology/volume_growth.go
@@ -152,9 +152,9 @@ func (vg *VolumeGrowth) findAndGrow(grpcDialOption grpc.DialOption, topo *Topolo
 		}
 	}()
 
-	for !topo.LastLeaderChangeTime.Add(constants.VolumePulseSeconds * 2).Before(time.Now()) {
+	for !topo.LastLeaderChangeTime.Add(constants.VolumePulsePeriod * 2).Before(time.Now()) {
 		glog.V(0).Infof("wait for volume servers to join back")
-		time.Sleep(constants.VolumePulseSeconds / 2)
+		time.Sleep(constants.VolumePulsePeriod / 2)
 	}
 	vid, raftErr := topo.NextVolumeId()
 	if raftErr != nil {