diff --git a/weed/shell/command_volume_balance.go b/weed/shell/command_volume_balance.go
index 8a7b53f82..1a0db8f88 100644
--- a/weed/shell/command_volume_balance.go
+++ b/weed/shell/command_volume_balance.go
@@ -26,17 +26,14 @@ func init() {
 	Commands = append(Commands, &commandVolumeBalance{})
 }
 
-var (
-	capacityByFunc = capacityByMaxVolumeCount
-)
-
-const funcNameCapByMinVolumeDensity = "capacityByMinVolumeDensity.func1"
+const thresholdVolumeSize = 1.01
 
 type commandVolumeBalance struct {
-	volumeSizeLimitMb uint64
 	commandEnv        *CommandEnv
+	capacityByFunc    CapacityByFunc
 	volumeByActive    *bool
 	applyBalancing    bool
+	volumeSizeLimitMb uint64
 }
 
 func (c *commandVolumeBalance) Name() string {
@@ -126,11 +123,12 @@ func (c *commandVolumeBalance) Do(args []string, commandEnv *CommandEnv, writer
 	})
 	balanceCommand.Func("capacityBy", "capacityBy function name use \"MAX_VOLUME_COUNT\", \"FREE_VOLUME_COUNT\" and \"MIN_VOLUME_DENSITY\"", func(flagValue string) error {
 		if flagValue == "" {
+			c.capacityByFunc = capacityByMaxVolumeCount
 			return nil
 		}
 		for allowed, allowedCapacityByFunc := range allowedCapacityBy {
 			if flagValue == allowed {
-				capacityByFunc = allowedCapacityByFunc
+				c.capacityByFunc = allowedCapacityByFunc
 				return nil
 			}
 		}
@@ -226,7 +224,7 @@ func (c *commandVolumeBalance) balanceVolumeServersByDiskType(diskType types.Dis
 			return selectVolumesByActive(v.Size, c.volumeByActive, c.volumeSizeLimitMb)
 		})
 	}
-	if err := balanceSelectedVolume(c.commandEnv, diskType, volumeReplicas, nodes, sortWritableVolumes, c.applyBalancing, c.volumeSizeLimitMb, c.volumeByActive); err != nil {
+	if err := balanceSelectedVolume(c.commandEnv, diskType, volumeReplicas, nodes, sortWritableVolumes, c.applyBalancing, c.volumeSizeLimitMb, c.capacityByFunc); err != nil {
 		return err
 	}
 
@@ -301,9 +299,9 @@ func capacityByMaxVolumeCount(diskType types.DiskType, volumeSizeLimitMb uint64)
 			ecShardCount += erasure_coding.GetShardCount(ecShardInfo)
 		}
 		if volumeSizeLimitMb == 0 {
-			volumeSizeLimitMb = util.VolumeSizeLimitGB * 1024
+			volumeSizeLimitMb = util.VolumeSizeLimitGB * util.KiByte
 		}
-		usedVolumeCount := volumeSizes / (volumeSizeLimitMb * 1024 * 1024)
+		usedVolumeCount := volumeSizes / (volumeSizeLimitMb * util.MiByte)
 
 		return float64(diskInfo.MaxVolumeCount) - float64(ecShardCount)/erasure_coding.DataShardsCount, usedVolumeCount, false
 	}
@@ -319,7 +317,10 @@ func capacityByMinVolumeDensity(diskType types.DiskType, volumeSizeLimitMb uint6
 		for _, volumeInfo := range diskInfo.VolumeInfos {
 			volumeSizes += volumeInfo.Size
 		}
-		usedVolumeCount := volumeSizes / (volumeSizeLimitMb * 1024 * 1024)
+		if volumeSizeLimitMb == 0 {
+			volumeSizeLimitMb = util.VolumeSizeLimitGB * util.KiByte
+		}
+		usedVolumeCount := volumeSizes / (volumeSizeLimitMb * util.MiByte)
 		return float64(uint64(diskInfo.MaxVolumeCount) - usedVolumeCount), usedVolumeCount, true
 	}
 }
@@ -339,9 +340,9 @@ func capacityByFreeVolumeCount(diskType types.DiskType, volumeSizeLimitMb uint64
 			ecShardCount += erasure_coding.GetShardCount(ecShardInfo)
 		}
 		if volumeSizeLimitMb == 0 {
-			volumeSizeLimitMb = util.VolumeSizeLimitGB * 1024
+			volumeSizeLimitMb = util.VolumeSizeLimitGB * util.KiByte
 		}
-		usedVolumeCount := volumeSizes / (volumeSizeLimitMb * 1024 * 1024)
+		usedVolumeCount := volumeSizes / (volumeSizeLimitMb * util.MiByte)
 		return float64(diskInfo.MaxVolumeCount-diskInfo.VolumeCount) - float64(ecShardCount)/erasure_coding.DataShardsCount, usedVolumeCount, false
 	}
 }
@@ -395,14 +396,14 @@ func selectVolumesByActive(volumeSize uint64, volumeByActive *bool, volumeSizeLi
 	if volumeByActive == nil {
 		return true
 	}
-	if (volumeSize*101)/100 < volumeSizeLimitMb*1024*1024 {
+	if uint64(float64(volumeSize)*thresholdVolumeSize) < volumeSizeLimitMb*util.MiByte {
 		return *volumeByActive
 	} else {
 		return !(*volumeByActive)
 	}
 }
 
-func balanceSelectedVolume(commandEnv *CommandEnv, diskType types.DiskType, volumeReplicas map[uint32][]*VolumeReplica, nodes []*Node, sortCandidatesFn func(volumes []*master_pb.VolumeInformationMessage), applyBalancing bool, volumeSizeLimitMb uint64, volumeByActive *bool) (err error) {
+func balanceSelectedVolume(commandEnv *CommandEnv, diskType types.DiskType, volumeReplicas map[uint32][]*VolumeReplica, nodes []*Node, sortCandidatesFn func(volumes []*master_pb.VolumeInformationMessage), applyBalancing bool, volumeSizeLimitMb uint64, capacityByFunc CapacityByFunc) (err error) {
 	ratioVolumeCount, volumeCapacities, idealVolumeRatio := uint64(0), float64(0), float64(0)
 	var nodesWithCapacity []*Node
 	capacityFunc := capacityByFunc(diskType, volumeSizeLimitMb)
diff --git a/weed/shell/command_volume_balance_test.go b/weed/shell/command_volume_balance_test.go
index 6c0a8d065..bdecf4be9 100644
--- a/weed/shell/command_volume_balance_test.go
+++ b/weed/shell/command_volume_balance_test.go
@@ -20,10 +20,6 @@ type testMoveCase struct {
 	expected       bool
 }
 
-func stringPtr(s string) *string {
-	return &s
-}
-
 func TestIsGoodMove(t *testing.T) {
 
 	var tests = []testMoveCase{
@@ -259,11 +255,14 @@ func TestBalance(t *testing.T) {
 	volumeServers := collectVolumeServersByDcRackNode(topologyInfo, "", "", "")
 	volumeReplicas, _ := collectVolumeReplicaLocations(topologyInfo)
 	diskTypes := collectVolumeDiskTypes(topologyInfo)
-	c := &commandVolumeBalance{}
+	c := &commandVolumeBalance{capacityByFunc: capacityByMaxVolumeCount}
+	if err := c.balanceVolumeServers(diskTypes, volumeReplicas, volumeServers, nil, "ALL_COLLECTIONS"); err != nil {
+		t.Errorf("balance: %v", err)
+	}
+	c = &commandVolumeBalance{capacityByFunc: capacityByMinVolumeDensity, volumeByActive: new(bool)}
 	if err := c.balanceVolumeServers(diskTypes, volumeReplicas, volumeServers, nil, "ALL_COLLECTIONS"); err != nil {
 		t.Errorf("balance: %v", err)
 	}
-
 }
 
 func TestVolumeSelection(t *testing.T) {