From 88c558ad7cb74f68c59228f8e6ca0bfd41a3520a Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Manuel=20R=C3=BCger?= <manuel@rueg.eu>
Date: Thu, 30 Jul 2026 03:25:44 +0200
Subject: [PATCH] plugin/kubernetes: preallocate slice capacities in controller
 query lookups (#8343)
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Signed-off-by: Manuel Rüger <manuel@rueg.eu>
---
 plugin/kubernetes/controller.go | 13 +++++++++++--
 1 file changed, 11 insertions(+), 2 deletions(-)

diff --git a/plugin/kubernetes/controller.go b/plugin/kubernetes/controller.go
index de4b9c355..b0c4bbefc 100644
--- a/plugin/kubernetes/controller.go
+++ b/plugin/kubernetes/controller.go
@@ -485,6 +485,7 @@ func (dns *dnsControl) HasSynced() bool {
 
 func (dns *dnsControl) ServiceList() (svcs []*object.Service) {
 	os := dns.svcLister.List()
+	svcs = make([]*object.Service, 0, len(os))
 	for _, o := range os {
 		s, ok := o.(*object.Service)
 		if !ok {
@@ -497,6 +498,7 @@ func (dns *dnsControl) ServiceList() (svcs []*object.Service) {
 
 func (dns *dnsControl) ServiceImportList() (svcs []*object.ServiceImport) {
 	os := dns.svcImportLister.List()
+	svcs = make([]*object.ServiceImport, 0, len(os))
 	for _, o := range os {
 		s, ok := o.(*object.ServiceImport)
 		if !ok {
@@ -509,6 +511,7 @@ func (dns *dnsControl) ServiceImportList() (svcs []*object.ServiceImport) {
 
 func (dns *dnsControl) EndpointsList() (eps []*object.Endpoints) {
 	os := dns.epLister.List()
+	eps = make([]*object.Endpoints, 0, len(os))
 	for _, o := range os {
 		ep, ok := o.(*object.Endpoints)
 		if !ok {
@@ -524,6 +527,7 @@ func (dns *dnsControl) PodIndex(ip string) (pods []*object.Pod) {
 	if err != nil {
 		return nil
 	}
+	pods = make([]*object.Pod, 0, len(os))
 	for _, o := range os {
 		p, ok := o.(*object.Pod)
 		if !ok {
@@ -539,6 +543,7 @@ func (dns *dnsControl) SvcIndex(idx string) (svcs []*object.Service) {
 	if err != nil {
 		return nil
 	}
+	svcs = make([]*object.Service, 0, len(os))
 	for _, o := range os {
 		s, ok := o.(*object.Service)
 		if !ok {
@@ -554,7 +559,7 @@ func (dns *dnsControl) SvcIndexReverse(ip string) (svcs []*object.Service) {
 	if err != nil {
 		return nil
 	}
-
+	svcs = make([]*object.Service, 0, len(os))
 	for _, o := range os {
 		s, ok := o.(*object.Service)
 		if !ok {
@@ -570,7 +575,7 @@ func (dns *dnsControl) SvcExtIndexReverse(ip string) (svcs []*object.Service) {
 	if err != nil {
 		return nil
 	}
-
+	svcs = make([]*object.Service, 0, len(os))
 	for _, o := range os {
 		s, ok := o.(*object.Service)
 		if !ok {
@@ -586,6 +591,7 @@ func (dns *dnsControl) SvcImportIndex(idx string) (svcs []*object.ServiceImport)
 	if err != nil {
 		return nil
 	}
+	svcs = make([]*object.ServiceImport, 0, len(os))
 	for _, o := range os {
 		s, ok := o.(*object.ServiceImport)
 		if !ok {
@@ -601,6 +607,7 @@ func (dns *dnsControl) EpIndex(idx string) (ep []*object.Endpoints) {
 	if err != nil {
 		return nil
 	}
+	ep = make([]*object.Endpoints, 0, len(os))
 	for _, o := range os {
 		e, ok := o.(*object.Endpoints)
 		if !ok {
@@ -616,6 +623,7 @@ func (dns *dnsControl) EpIndexReverse(ip string) (ep []*object.Endpoints) {
 	if err != nil {
 		return nil
 	}
+	ep = make([]*object.Endpoints, 0, len(os))
 	for _, o := range os {
 		e, ok := o.(*object.Endpoints)
 		if !ok {
@@ -631,6 +639,7 @@ func (dns *dnsControl) McEpIndex(idx string) (ep []*object.MultiClusterEndpoints
 	if err != nil {
 		return nil
 	}
+	ep = make([]*object.MultiClusterEndpoints, 0, len(os))
 	for _, o := range os {
 		e, ok := o.(*object.MultiClusterEndpoints)
 		if !ok {