diff --git a/pkg/planner/core/operator/logicalop/logical_aggregation.go b/pkg/planner/core/operator/logicalop/logical_aggregation.go
index 88968dba476ef..391784a5205c3 100644
--- a/pkg/planner/core/operator/logicalop/logical_aggregation.go
+++ b/pkg/planner/core/operator/logicalop/logical_aggregation.go
@@ -135,8 +135,7 @@ func (la *LogicalAggregation) PruneColumns(parentUsedCols []*expression.Column,
 	}
 	logicaltrace.AppendColumnPruneTraceStep(la, prunedColumns, opt)
 	logicaltrace.AppendFunctionPruneTraceStep(la, prunedFunctions, opt)
-	//nolint: prealloc
-	var selfUsedCols []*expression.Column
+	selfUsedCols := make([]*expression.Column, 0, 5)
 	for _, aggrFunc := range la.AggFuncs {
 		selfUsedCols = expression.ExtractColumnsFromExpressions(selfUsedCols, aggrFunc.Args, nil)
 
@@ -597,13 +596,12 @@ func (la *LogicalAggregation) pushDownCNFPredicatesForAggregation(cond expressio
 // (a > 1 and avg(b) > 1) or (a < 3), and `avg(b) > 1` can't be pushed-down.
 // Then condsToPush: (a < 3) and (a > 1), ret: (a > 1 and avg(b) > 1) or (a < 3)
 func (la *LogicalAggregation) pushDownDNFPredicatesForAggregation(cond expression.Expression, groupByColumns *expression.Schema, exprsOriginal []expression.Expression) ([]expression.Expression, []expression.Expression) {
-	//nolint: prealloc
-	var condsToPush []expression.Expression
-	var ret []expression.Expression
 	subDNFItem := expression.SplitDNFItems(cond)
 	if len(subDNFItem) == 1 {
 		return la.pushDownPredicatesForAggregation(subDNFItem[0], groupByColumns, exprsOriginal)
 	}
+	condsToPush := make([]expression.Expression, 0, len(subDNFItem))
+	var ret []expression.Expression
 	exprCtx := la.SCtx().GetExprCtx()
 	for _, item := range subDNFItem {
 		condsToPushForItem, retForItem := la.pushDownCNFPredicatesForAggregation(item, groupByColumns, exprsOriginal)
diff --git a/pkg/planner/core/rule_join_reorder.go b/pkg/planner/core/rule_join_reorder.go
index 1bd970609dff3..81dc479b560f0 100644
--- a/pkg/planner/core/rule_join_reorder.go
+++ b/pkg/planner/core/rule_join_reorder.go
@@ -796,8 +796,7 @@ func findRoots(t *tracing.PlanTrace) []*tracing.PlanTrace {
 	if t.TP == plancodec.TypeJoin || t.TP == plancodec.TypeDataSource {
 		return []*tracing.PlanTrace{t}
 	}
-	//nolint: prealloc
-	var r []*tracing.PlanTrace
+	r := make([]*tracing.PlanTrace, 0, 5)
 	for _, child := range t.Children {
 		r = append(r, findRoots(child)...)
 	}
diff --git a/pkg/planner/core/rule_join_reorder_dp.go b/pkg/planner/core/rule_join_reorder_dp.go
index 804a5714f88fd..860e7d7ee6d32 100644
--- a/pkg/planner/core/rule_join_reorder_dp.go
+++ b/pkg/planner/core/rule_join_reorder_dp.go
@@ -216,11 +216,7 @@ func (s *joinReorderDPSolver) dpGraph(visitID2NodeID, nodeID2VisitID []int, _ []
 
 func (*joinReorderDPSolver) nodesAreConnected(leftMask, rightMask uint, oldPos2NewPos []int,
 	totalEqEdges []joinGroupEqEdge, totalNonEqEdges []joinGroupNonEqEdge) ([]joinGroupEqEdge, []expression.Expression) {
-	//nolint: prealloc
 	var usedEqEdges []joinGroupEqEdge
-	//nolint: prealloc
-	var otherConds []expression.Expression
-
 	for _, edge := range totalEqEdges {
 		lIdx := uint(oldPos2NewPos[edge.nodeIDs[0]])
 		rIdx := uint(oldPos2NewPos[edge.nodeIDs[1]])
@@ -228,6 +224,7 @@ func (*joinReorderDPSolver) nodesAreConnected(leftMask, rightMask uint, oldPos2N
 			usedEqEdges = append(usedEqEdges, edge)
 		}
 	}
+	otherConds := make([]expression.Expression, 0, len(totalNonEqEdges))
 	for _, edge := range totalNonEqEdges {
 		// If the result is false, means that the current group hasn't covered the columns involved in the expression.
 		if edge.nodeIDMask&(leftMask|rightMask) != edge.nodeIDMask {