diff --git a/internal/querycoordv2/balance/multi_target_balance.go b/internal/querycoordv2/balance/multi_target_balance.go
index 21f9b9df95..d8e21c6806 100644
--- a/internal/querycoordv2/balance/multi_target_balance.go
+++ b/internal/querycoordv2/balance/multi_target_balance.go
@@ -96,7 +96,7 @@ func (m *segmentCountCostModel) cost() float64 {
 	return (currCost - best) / (worst - best)
 }
 
-func cmpFloat(f1, f2 float64) int {
+func cmpCost(f1, f2 float64) int {
 	if math.Abs(f1-f2) < params.Params.QueryCoordCfg.BalanceCostThreshold.GetAsFloat() {
 		return 0
 	}
@@ -279,7 +279,7 @@ func (g *rowCountBasedPlanGenerator) generatePlans() []SegmentAssignPlan {
 		newCluster := g.applyPlans(g.replicaNodeSegments, []SegmentAssignPlan{plan})
 		newGlobalCluster := g.applyPlans(g.globalNodeSegments, []SegmentAssignPlan{plan})
 		newCost := g.calClusterCost(newCluster, newGlobalCluster)
-		if cmpFloat(newCost, g.currClusterCost) < 0 {
+		if cmpCost(newCost, g.currClusterCost) < 0 {
 			g.currClusterCost = newCost
 			g.replicaNodeSegments = newCluster
 			g.globalNodeSegments = newGlobalCluster
@@ -356,7 +356,7 @@ func (g *segmentCountBasedPlanGenerator) generatePlans() []SegmentAssignPlan {
 		newCluster := g.applyPlans(g.replicaNodeSegments, []SegmentAssignPlan{plan})
 		newGlobalCluster := g.applyPlans(g.globalNodeSegments, []SegmentAssignPlan{plan})
 		newCost := g.calClusterCost(newCluster, newGlobalCluster)
-		if cmpFloat(newCost, g.currClusterCost) < 0 {
+		if cmpCost(newCost, g.currClusterCost) < 0 {
 			g.currClusterCost = newCost
 			g.replicaNodeSegments = newCluster
 			g.globalNodeSegments = newGlobalCluster
@@ -440,7 +440,7 @@ func (g *randomPlanGenerator) generatePlans() []SegmentAssignPlan {
 		newCluster := g.applyPlans(g.replicaNodeSegments, plans)
 		newGlobalCluster := g.applyPlans(g.globalNodeSegments, plans)
 		newCost := g.calClusterCost(newCluster, newGlobalCluster)
-		if cmpFloat(newCost, g.currClusterCost) < 0 {
+		if cmpCost(newCost, g.currClusterCost) < 0 {
 			g.currClusterCost = newCost
 			g.replicaNodeSegments = newCluster
 			g.globalNodeSegments = newGlobalCluster
diff --git a/pkg/util/paramtable/component_param.go b/pkg/util/paramtable/component_param.go
index e4c5800eee..df37b7fb26 100644
--- a/pkg/util/paramtable/component_param.go
+++ b/pkg/util/paramtable/component_param.go
@@ -1606,10 +1606,10 @@ func (p *queryCoordConfig) init(base *BaseTable) {
 
 	p.BalanceCostThreshold = ParamItem{
 		Key:          "queryCoord.balanceCostThreshold",
-		Version:      "2.3.5",
+		Version:      "2.4.0",
 		DefaultValue: "0.001",
 		PanicIfEmpty: true,
-		Doc:          "the threshold of balance cost",
+		Doc:          "the threshold of balance cost, if the difference of cluster's cost after executing the balance plan is less than this value, the plan will not be executed",
 		Export:       true,
 	}
 	p.BalanceCostThreshold.Init(base.mgr)