diff --git a/internal/metastore/model/collection.go b/internal/metastore/model/collection.go
index 66acf68cf248c..08f6cf08ff1c0 100644
--- a/internal/metastore/model/collection.go
+++ b/internal/metastore/model/collection.go
@@ -34,6 +34,29 @@ func (c *Collection) Available() bool {
 	return c.State == pb.CollectionState_CollectionCreated
 }
 
+func (c *Collection) ShadowClone() *Collection {
+	return &Collection{
+		TenantID:             c.TenantID,
+		DBID:                 c.DBID,
+		CollectionID:         c.CollectionID,
+		Name:                 c.Name,
+		Description:          c.Description,
+		AutoID:               c.AutoID,
+		Fields:               c.Fields,
+		Partitions:           c.Partitions,
+		VirtualChannelNames:  c.VirtualChannelNames,
+		PhysicalChannelNames: c.PhysicalChannelNames,
+		ShardsNum:            c.ShardsNum,
+		ConsistencyLevel:     c.ConsistencyLevel,
+		CreateTime:           c.CreateTime,
+		StartPositions:       c.StartPositions,
+		Aliases:              c.Aliases,
+		Properties:           c.Properties,
+		State:                c.State,
+		EnableDynamicField:   c.EnableDynamicField,
+	}
+}
+
 func (c *Collection) Clone() *Collection {
 	return &Collection{
 		TenantID:             c.TenantID,
diff --git a/internal/rootcoord/meta_table.go b/internal/rootcoord/meta_table.go
index 8616ce6dc9092..f84055d5495ec 100644
--- a/internal/rootcoord/meta_table.go
+++ b/internal/rootcoord/meta_table.go
@@ -537,12 +537,12 @@ func (mt *MetaTable) RemoveCollection(ctx context.Context, collectionID UniqueID
 }
 
 func filterUnavailable(coll *model.Collection) *model.Collection {
-	clone := coll.Clone()
+	clone := coll.ShadowClone()
 	// pick available partitions.
-	clone.Partitions = nil
+	clone.Partitions = make([]*model.Partition, 0, len(coll.Partitions))
 	for _, partition := range coll.Partitions {
 		if partition.Available() {
-			clone.Partitions = append(clone.Partitions, partition.Clone())
+			clone.Partitions = append(clone.Partitions, partition)
 		}
 	}
 	return clone