From 929c7ce08cfc123c27300e544beca03066bd5cd1 Mon Sep 17 00:00:00 2001
From: ystaticy <y_static_y@sina.com>
Date: Wed, 29 Apr 2026 09:54:59 +0800
Subject: [PATCH 01/21]  support default RU group

Signed-off-by: ystaticy <y_static_y@sina.com>
---
 pkg/domain/BUILD.bazel     |   6 +-
 pkg/domain/runaway.go      |  40 ++++++++++-
 pkg/domain/runaway_test.go | 132 +++++++++++++++++++++++++++++++++++++
 3 files changed, 176 insertions(+), 2 deletions(-)
 create mode 100644 pkg/domain/runaway_test.go

diff --git a/pkg/domain/BUILD.bazel b/pkg/domain/BUILD.bazel
index 3971bd44c7d60..f86bc3d6bd21a 100644
--- a/pkg/domain/BUILD.bazel
+++ b/pkg/domain/BUILD.bazel
@@ -116,6 +116,7 @@ go_library(
         "@com_github_pingcap_failpoint//:failpoint",
         "@com_github_pingcap_kvproto//pkg/metapb",
         "@com_github_pingcap_kvproto//pkg/pdpb",
+        "@com_github_pingcap_kvproto//pkg/resource_manager",
         "@com_github_pingcap_log//:log",
         "@com_github_pingcap_metering_sdk//config",
         "@com_github_stretchr_testify//require",
@@ -148,12 +149,13 @@ go_test(
         "plan_replayer_slow_log_test.go",
         "plan_replayer_test.go",
         "ru_stats_test.go",
+        "runaway_test.go",
         "schema_checker_test.go",
         "topn_slow_query_test.go",
     ],
     embed = [":domain"],
     flaky = True,
-    shard_count = 30,
+    shard_count = 31,
     deps = [
         "//pkg/config",
         "//pkg/ddl",
@@ -173,6 +175,7 @@ go_test(
         "//pkg/parser/mysql",
         "//pkg/parser/terror",
         "//pkg/planner/extstore",
+        "//pkg/resourcegroup/runaway",
         "//pkg/server",
         "//pkg/session",
         "//pkg/sessionctx/vardef",
@@ -190,6 +193,7 @@ go_test(
         "@com_github_ngaut_pools//:pools",
         "@com_github_pingcap_errors//:errors",
         "@com_github_pingcap_failpoint//:failpoint",
+        "@com_github_pingcap_kvproto//pkg/meta_storagepb",
         "@com_github_pingcap_kvproto//pkg/metapb",
         "@com_github_pingcap_kvproto//pkg/resource_manager",
         "@com_github_prometheus_client_model//go",
diff --git a/pkg/domain/runaway.go b/pkg/domain/runaway.go
index ae1f2d6d233c2..e3f9639fc8460 100644
--- a/pkg/domain/runaway.go
+++ b/pkg/domain/runaway.go
@@ -17,8 +17,12 @@ package domain
 import (
 	"context"
 	"net"
+	"os"
 	"strconv"
+	"strings"
+	"time"
 
+	rmpb "github.com/pingcap/kvproto/pkg/resource_manager"
 	"github.com/pingcap/tidb/pkg/domain/infosync"
 	"github.com/pingcap/tidb/pkg/resourcegroup/runaway"
 	"github.com/pingcap/tidb/pkg/util/logutil"
@@ -28,6 +32,40 @@ import (
 	rmclient "github.com/tikv/pd/client/resource_group/controller"
 )
 
+const (
+	defaultDegradedRUFillRate      = 2_000_000
+	defaultDegradedRUBurstLimit    = 50_000_000_000
+	defaultDegradedModeWaitTimeout = 3 * time.Second / 2
+	vipWaitRetryInterval           = 100 * time.Millisecond
+	vipWaitRetryTimes              = 20
+)
+
+func newDefaultDegradedRUSettings() *rmpb.GroupRequestUnitSettings {
+	return &rmpb.GroupRequestUnitSettings{
+		RU: &rmpb.TokenBucket{
+			Settings: &rmpb.TokenLimitSettings{
+				FillRate:   defaultDegradedRUFillRate,
+				BurstLimit: defaultDegradedRUBurstLimit,
+			},
+		},
+	}
+}
+
+func newResourceGroupsControllerOptions() []rmclient.ResourceControlCreateOption {
+	opts := []rmclient.ResourceControlCreateOption{
+		rmclient.WithMaxWaitDuration(runaway.MaxWaitDuration),
+		rmclient.WithDegradedModeWaitDuration(defaultDegradedModeWaitTimeout),
+		rmclient.WithDegradedRUSettings(newDefaultDegradedRUSettings()),
+	}
+	if strings.Contains(os.Getenv("NAMESPACE"), "vip") {
+		opts = append(opts,
+			rmclient.WithWaitRetryInterval(vipWaitRetryInterval),
+			rmclient.WithWaitRetryTimes(vipWaitRetryTimes),
+		)
+	}
+	return opts
+}
+
 func (do *Domain) initResourceGroupsController(ctx context.Context, pdClient pd.Client, uniqueID uint64) error {
 	if pdClient == nil {
 		logutil.BgLogger().Warn("cannot setup up resource controller, not using tikv storage")
@@ -39,7 +77,7 @@ func (do *Domain) initResourceGroupsController(ctx context.Context, pdClient pd.
 	if codec := do.Store().GetCodec(); codec != nil {
 		keyspaceID = uint32(codec.GetKeyspaceID())
 	}
-	control, err := rmclient.NewResourceGroupController(ctx, uniqueID, pdClient, nil, keyspaceID, rmclient.WithMaxWaitDuration(runaway.MaxWaitDuration))
+	control, err := rmclient.NewResourceGroupController(ctx, uniqueID, pdClient, nil, keyspaceID, newResourceGroupsControllerOptions()...)
 	if err != nil {
 		return err
 	}
diff --git a/pkg/domain/runaway_test.go b/pkg/domain/runaway_test.go
new file mode 100644
index 0000000000000..7f39a3bb350b2
--- /dev/null
+++ b/pkg/domain/runaway_test.go
@@ -0,0 +1,132 @@
+// Copyright 2026 PingCAP, Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package domain
+
+import (
+	"context"
+	"errors"
+	"testing"
+
+	"github.com/pingcap/kvproto/pkg/meta_storagepb"
+	rmpb "github.com/pingcap/kvproto/pkg/resource_manager"
+	"github.com/pingcap/tidb/pkg/resourcegroup/runaway"
+	"github.com/stretchr/testify/require"
+	pd "github.com/tikv/pd/client"
+	"github.com/tikv/pd/client/opt"
+	rmclient "github.com/tikv/pd/client/resource_group/controller"
+)
+
+type resourceGroupProviderStub struct {
+	resourceGroup *rmpb.ResourceGroup
+	resourceErr   error
+}
+
+func (s *resourceGroupProviderStub) GetResourceGroup(context.Context, string, ...pd.GetResourceGroupOption) (*rmpb.ResourceGroup, error) {
+	return s.resourceGroup, s.resourceErr
+}
+
+func (s *resourceGroupProviderStub) ListResourceGroups(context.Context, ...pd.GetResourceGroupOption) ([]*rmpb.ResourceGroup, error) {
+	return nil, nil
+}
+
+func (s *resourceGroupProviderStub) AddResourceGroup(context.Context, *rmpb.ResourceGroup) (string, error) {
+	return "", nil
+}
+
+func (s *resourceGroupProviderStub) ModifyResourceGroup(context.Context, *rmpb.ResourceGroup) (string, error) {
+	return "", nil
+}
+
+func (s *resourceGroupProviderStub) DeleteResourceGroup(context.Context, string) (string, error) {
+	return "", nil
+}
+
+func (s *resourceGroupProviderStub) AcquireTokenBuckets(context.Context, *rmpb.TokenBucketsRequest) ([]*rmpb.TokenBucketResponse, error) {
+	return nil, nil
+}
+
+func (s *resourceGroupProviderStub) LoadResourceGroups(context.Context) ([]*rmpb.ResourceGroup, int64, error) {
+	return nil, 0, nil
+}
+
+func (s *resourceGroupProviderStub) Watch(context.Context, []byte, ...opt.MetaStorageOption) (chan []*meta_storagepb.Event, error) {
+	return make(chan []*meta_storagepb.Event), nil
+}
+
+func (s *resourceGroupProviderStub) Get(context.Context, []byte, ...opt.MetaStorageOption) (*meta_storagepb.GetResponse, error) {
+	return &meta_storagepb.GetResponse{Header: &meta_storagepb.ResponseHeader{}}, nil
+}
+
+func (s *resourceGroupProviderStub) Put(context.Context, []byte, []byte, ...opt.MetaStorageOption) (*meta_storagepb.PutResponse, error) {
+	return &meta_storagepb.PutResponse{Header: &meta_storagepb.ResponseHeader{}}, nil
+}
+
+func TestResourceGroupsControllerOptionsProvideDegradedFallback(t *testing.T) {
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+
+	provider := &resourceGroupProviderStub{
+		resourceGroup: &rmpb.ResourceGroup{
+			Name: "test-group",
+			Mode: rmpb.GroupMode_RUMode,
+			RUSettings: &rmpb.GroupRequestUnitSettings{
+				RU: &rmpb.TokenBucket{
+					Settings: &rmpb.TokenLimitSettings{FillRate: 1},
+				},
+			},
+		},
+		resourceErr: errors.New("resource group unavailable"),
+	}
+
+	controllerWithFallback, err := rmclient.NewResourceGroupController(
+		ctx,
+		1,
+		provider,
+		nil,
+		0,
+		newResourceGroupsControllerOptions()...,
+	)
+	require.NoError(t, err)
+	controllerWithFallback.Start(ctx)
+	defer func() {
+		require.NoError(t, controllerWithFallback.Stop())
+	}()
+
+	group, err := controllerWithFallback.GetResourceGroup("test-group")
+	require.NoError(t, err)
+	require.Equal(t, &rmpb.ResourceGroup{
+		Name:       "test-group",
+		Mode:       rmpb.GroupMode_RUMode,
+		RUSettings: newDefaultDegradedRUSettings(),
+	}, group)
+
+	controllerWithoutFallback, err := rmclient.NewResourceGroupController(
+		ctx,
+		2,
+		provider,
+		nil,
+		0,
+		rmclient.WithMaxWaitDuration(runaway.MaxWaitDuration),
+	)
+	require.NoError(t, err)
+	controllerWithoutFallback.Start(ctx)
+	defer func() {
+		require.NoError(t, controllerWithoutFallback.Stop())
+	}()
+
+	group, err = controllerWithoutFallback.GetResourceGroup("test-group")
+	require.Error(t, err)
+	require.Nil(t, group)
+}

From 40d3deabfa85902a443c0536035d0e5ccd5c698e Mon Sep 17 00:00:00 2001
From: ystaticy <y_static_y@sina.com>
Date: Sun, 5 Jul 2026 15:28:31 +0800
Subject: [PATCH 02/21]  only in starter

Signed-off-by: ystaticy <y_static_y@sina.com>
---
 pkg/domain/BUILD.bazel     |  3 ++-
 pkg/domain/runaway.go      | 13 +++++++++++--
 pkg/domain/runaway_test.go | 11 +++++++++--
 3 files changed, 22 insertions(+), 5 deletions(-)

diff --git a/pkg/domain/BUILD.bazel b/pkg/domain/BUILD.bazel
index f86bc3d6bd21a..b9c86014f1942 100644
--- a/pkg/domain/BUILD.bazel
+++ b/pkg/domain/BUILD.bazel
@@ -108,6 +108,7 @@ go_library(
         "//pkg/util/sqlexec",
         "//pkg/util/sqlkiller",
         "//pkg/util/syncutil",
+        "//pkg/util/versioninfo",
         "//pkg/workloadlearning",
         "@com_github_burntsushi_toml//:toml",
         "@com_github_docker_go_units//:go-units",
@@ -175,7 +176,6 @@ go_test(
         "//pkg/parser/mysql",
         "//pkg/parser/terror",
         "//pkg/planner/extstore",
-        "//pkg/resourcegroup/runaway",
         "//pkg/server",
         "//pkg/session",
         "//pkg/sessionctx/vardef",
@@ -190,6 +190,7 @@ go_test(
         "//pkg/util/mock",
         "//pkg/util/replayer",
         "//pkg/util/stmtsummary/v2:stmtsummary",
+        "//pkg/util/versioninfo",
         "@com_github_ngaut_pools//:pools",
         "@com_github_pingcap_errors//:errors",
         "@com_github_pingcap_failpoint//:failpoint",
diff --git a/pkg/domain/runaway.go b/pkg/domain/runaway.go
index e3f9639fc8460..4727b6de6b68e 100644
--- a/pkg/domain/runaway.go
+++ b/pkg/domain/runaway.go
@@ -26,6 +26,7 @@ import (
 	"github.com/pingcap/tidb/pkg/domain/infosync"
 	"github.com/pingcap/tidb/pkg/resourcegroup/runaway"
 	"github.com/pingcap/tidb/pkg/util/logutil"
+	"github.com/pingcap/tidb/pkg/util/versioninfo"
 	"github.com/tikv/client-go/v2/tikv"
 	pd "github.com/tikv/pd/client"
 	"github.com/tikv/pd/client/constants"
@@ -40,6 +41,10 @@ const (
 	vipWaitRetryTimes              = 20
 )
 
+func isStarter() bool {
+	return versioninfo.TiDBEdition == "Starter"
+}
+
 func newDefaultDegradedRUSettings() *rmpb.GroupRequestUnitSettings {
 	return &rmpb.GroupRequestUnitSettings{
 		RU: &rmpb.TokenBucket{
@@ -54,8 +59,12 @@ func newDefaultDegradedRUSettings() *rmpb.GroupRequestUnitSettings {
 func newResourceGroupsControllerOptions() []rmclient.ResourceControlCreateOption {
 	opts := []rmclient.ResourceControlCreateOption{
 		rmclient.WithMaxWaitDuration(runaway.MaxWaitDuration),
-		rmclient.WithDegradedModeWaitDuration(defaultDegradedModeWaitTimeout),
-		rmclient.WithDegradedRUSettings(newDefaultDegradedRUSettings()),
+	}
+	if isStarter() {
+		opts = append(opts,
+			rmclient.WithDegradedModeWaitDuration(defaultDegradedModeWaitTimeout),
+			rmclient.WithDegradedRUSettings(newDefaultDegradedRUSettings()),
+		)
 	}
 	if strings.Contains(os.Getenv("NAMESPACE"), "vip") {
 		opts = append(opts,
diff --git a/pkg/domain/runaway_test.go b/pkg/domain/runaway_test.go
index 7f39a3bb350b2..6aef80ead2047 100644
--- a/pkg/domain/runaway_test.go
+++ b/pkg/domain/runaway_test.go
@@ -21,7 +21,7 @@ import (
 
 	"github.com/pingcap/kvproto/pkg/meta_storagepb"
 	rmpb "github.com/pingcap/kvproto/pkg/resource_manager"
-	"github.com/pingcap/tidb/pkg/resourcegroup/runaway"
+	"github.com/pingcap/tidb/pkg/util/versioninfo"
 	"github.com/stretchr/testify/require"
 	pd "github.com/tikv/pd/client"
 	"github.com/tikv/pd/client/opt"
@@ -74,6 +74,11 @@ func (s *resourceGroupProviderStub) Put(context.Context, []byte, []byte, ...opt.
 }
 
 func TestResourceGroupsControllerOptionsProvideDegradedFallback(t *testing.T) {
+	originalEdition := versioninfo.TiDBEdition
+	t.Cleanup(func() {
+		versioninfo.TiDBEdition = originalEdition
+	})
+
 	ctx, cancel := context.WithCancel(context.Background())
 	defer cancel()
 
@@ -90,6 +95,7 @@ func TestResourceGroupsControllerOptionsProvideDegradedFallback(t *testing.T) {
 		resourceErr: errors.New("resource group unavailable"),
 	}
 
+	versioninfo.TiDBEdition = "Starter"
 	controllerWithFallback, err := rmclient.NewResourceGroupController(
 		ctx,
 		1,
@@ -112,13 +118,14 @@ func TestResourceGroupsControllerOptionsProvideDegradedFallback(t *testing.T) {
 		RUSettings: newDefaultDegradedRUSettings(),
 	}, group)
 
+	versioninfo.TiDBEdition = versioninfo.CommunityEdition
 	controllerWithoutFallback, err := rmclient.NewResourceGroupController(
 		ctx,
 		2,
 		provider,
 		nil,
 		0,
-		rmclient.WithMaxWaitDuration(runaway.MaxWaitDuration),
+		newResourceGroupsControllerOptions()...,
 	)
 	require.NoError(t, err)
 	controllerWithoutFallback.Start(ctx)

From df69722b5064f6568940a8767f80c4caaa6d9c6c Mon Sep 17 00:00:00 2001
From: ystaticy <y_static_y@sina.com>
Date: Sun, 5 Jul 2026 16:48:19 +0800
Subject: [PATCH 03/21]  fix name

Signed-off-by: ystaticy <y_static_y@sina.com>
---
 pkg/domain/runaway.go | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/pkg/domain/runaway.go b/pkg/domain/runaway.go
index 4727b6de6b68e..8014e51ee86d5 100644
--- a/pkg/domain/runaway.go
+++ b/pkg/domain/runaway.go
@@ -37,8 +37,8 @@ const (
 	defaultDegradedRUFillRate      = 2_000_000
 	defaultDegradedRUBurstLimit    = 50_000_000_000
 	defaultDegradedModeWaitTimeout = 3 * time.Second / 2
-	vipWaitRetryInterval           = 100 * time.Millisecond
-	vipWaitRetryTimes              = 20
+	tokenWaitRetryInterval         = 100 * time.Millisecond
+	tokenWaitRetryTimes            = 20
 )
 
 func isStarter() bool {
@@ -68,8 +68,8 @@ func newResourceGroupsControllerOptions() []rmclient.ResourceControlCreateOption
 	}
 	if strings.Contains(os.Getenv("NAMESPACE"), "vip") {
 		opts = append(opts,
-			rmclient.WithWaitRetryInterval(vipWaitRetryInterval),
-			rmclient.WithWaitRetryTimes(vipWaitRetryTimes),
+			rmclient.WithWaitRetryInterval(tokenWaitRetryInterval),
+			rmclient.WithWaitRetryTimes(tokenWaitRetryTimes),
 		)
 	}
 	return opts

From 6d1ebffc70a594af1e1bdffb50ef3697d94f0348 Mon Sep 17 00:00:00 2001
From: ystaticy <y_static_y@sina.com>
Date: Sun, 5 Jul 2026 18:07:06 +0800
Subject: [PATCH 04/21] domain: use deploy mode for Starter RU fallback

---
 pkg/domain/BUILD.bazel     |  4 +--
 pkg/domain/runaway.go      |  8 ++----
 pkg/domain/runaway_test.go | 58 +++++++++++++++++++++++++++++++++-----
 3 files changed, 55 insertions(+), 15 deletions(-)

diff --git a/pkg/domain/BUILD.bazel b/pkg/domain/BUILD.bazel
index 29a808390b8f2..f008e43432cb8 100644
--- a/pkg/domain/BUILD.bazel
+++ b/pkg/domain/BUILD.bazel
@@ -108,7 +108,6 @@ go_library(
         "//pkg/util/sqlexec",
         "//pkg/util/sqlkiller",
         "//pkg/util/syncutil",
-        "//pkg/util/versioninfo",
         "//pkg/workloadlearning",
         "@com_github_burntsushi_toml//:toml",
         "@com_github_docker_go_units//:go-units",
@@ -160,6 +159,8 @@ go_test(
     shard_count = 31,
     deps = [
         "//pkg/config",
+        "//pkg/config/deploymode",
+        "//pkg/config/kerneltype",
         "//pkg/ddl",
         "//pkg/domain/infosync",
         "//pkg/domain/serverinfo",
@@ -191,7 +192,6 @@ go_test(
         "//pkg/util/mock",
         "//pkg/util/replayer",
         "//pkg/util/stmtsummary/v2:stmtsummary",
-        "//pkg/util/versioninfo",
         "@com_github_ngaut_pools//:pools",
         "@com_github_pingcap_errors//:errors",
         "@com_github_pingcap_failpoint//:failpoint",
diff --git a/pkg/domain/runaway.go b/pkg/domain/runaway.go
index 8014e51ee86d5..486c38ac7c53d 100644
--- a/pkg/domain/runaway.go
+++ b/pkg/domain/runaway.go
@@ -23,10 +23,10 @@ import (
 	"time"
 
 	rmpb "github.com/pingcap/kvproto/pkg/resource_manager"
+	"github.com/pingcap/tidb/pkg/config/deploymode"
 	"github.com/pingcap/tidb/pkg/domain/infosync"
 	"github.com/pingcap/tidb/pkg/resourcegroup/runaway"
 	"github.com/pingcap/tidb/pkg/util/logutil"
-	"github.com/pingcap/tidb/pkg/util/versioninfo"
 	"github.com/tikv/client-go/v2/tikv"
 	pd "github.com/tikv/pd/client"
 	"github.com/tikv/pd/client/constants"
@@ -41,10 +41,6 @@ const (
 	tokenWaitRetryTimes            = 20
 )
 
-func isStarter() bool {
-	return versioninfo.TiDBEdition == "Starter"
-}
-
 func newDefaultDegradedRUSettings() *rmpb.GroupRequestUnitSettings {
 	return &rmpb.GroupRequestUnitSettings{
 		RU: &rmpb.TokenBucket{
@@ -60,7 +56,7 @@ func newResourceGroupsControllerOptions() []rmclient.ResourceControlCreateOption
 	opts := []rmclient.ResourceControlCreateOption{
 		rmclient.WithMaxWaitDuration(runaway.MaxWaitDuration),
 	}
-	if isStarter() {
+	if deploymode.IsStarter() {
 		opts = append(opts,
 			rmclient.WithDegradedModeWaitDuration(defaultDegradedModeWaitTimeout),
 			rmclient.WithDegradedRUSettings(newDefaultDegradedRUSettings()),
diff --git a/pkg/domain/runaway_test.go b/pkg/domain/runaway_test.go
index 6aef80ead2047..cebd66530a5cf 100644
--- a/pkg/domain/runaway_test.go
+++ b/pkg/domain/runaway_test.go
@@ -21,7 +21,8 @@ import (
 
 	"github.com/pingcap/kvproto/pkg/meta_storagepb"
 	rmpb "github.com/pingcap/kvproto/pkg/resource_manager"
-	"github.com/pingcap/tidb/pkg/util/versioninfo"
+	"github.com/pingcap/tidb/pkg/config/deploymode"
+	"github.com/pingcap/tidb/pkg/config/kerneltype"
 	"github.com/stretchr/testify/require"
 	pd "github.com/tikv/pd/client"
 	"github.com/tikv/pd/client/opt"
@@ -33,10 +34,15 @@ type resourceGroupProviderStub struct {
 	resourceErr   error
 }
 
+// GetResourceGroup returns both the mocked resource group and the mocked error.
+// This lets the test verify whether the controller uses the degraded fallback
+// only for the editions that enable it.
 func (s *resourceGroupProviderStub) GetResourceGroup(context.Context, string, ...pd.GetResourceGroupOption) (*rmpb.ResourceGroup, error) {
 	return s.resourceGroup, s.resourceErr
 }
 
+// The remaining methods only satisfy the controller's provider dependencies.
+// The fallback test does not exercise their behavior.
 func (s *resourceGroupProviderStub) ListResourceGroups(context.Context, ...pd.GetResourceGroupOption) ([]*rmpb.ResourceGroup, error) {
 	return nil, nil
 }
@@ -74,14 +80,21 @@ func (s *resourceGroupProviderStub) Put(context.Context, []byte, []byte, ...opt.
 }
 
 func TestResourceGroupsControllerOptionsProvideDegradedFallback(t *testing.T) {
-	originalEdition := versioninfo.TiDBEdition
-	t.Cleanup(func() {
-		versioninfo.TiDBEdition = originalEdition
-	})
+	if kerneltype.IsNextGen() {
+		// Preserve the process-wide deploy mode because deploymode.IsStarter reads
+		// it directly when newResourceGroupsControllerOptions builds controller options.
+		originalDeployMode := deploymode.Get()
+		t.Cleanup(func() {
+			require.NoError(t, deploymode.Set(originalDeployMode))
+		})
+	}
 
+	// Use one cancelable context for the short-lived controllers created below.
 	ctx, cancel := context.WithCancel(context.Background())
 	defer cancel()
 
+	// Return a normal resource group together with an error. The error path is
+	// what should trigger the degraded RU fallback in Starter mode.
 	provider := &resourceGroupProviderStub{
 		resourceGroup: &rmpb.ResourceGroup{
 			Name: "test-group",
@@ -95,7 +108,32 @@ func TestResourceGroupsControllerOptionsProvideDegradedFallback(t *testing.T) {
 		resourceErr: errors.New("resource group unavailable"),
 	}
 
-	versioninfo.TiDBEdition = "Starter"
+	if !kerneltype.IsNextGen() {
+		// In classic builds deploymode.IsStarter is always false. This still guards
+		// against accidentally enabling degraded fallback outside NextGen Starter.
+		controller, err := rmclient.NewResourceGroupController(
+			ctx,
+			1,
+			provider,
+			nil,
+			0,
+			newResourceGroupsControllerOptions()...,
+		)
+		require.NoError(t, err)
+		controller.Start(ctx)
+		defer func() {
+			require.NoError(t, controller.Stop())
+		}()
+
+		group, err := controller.GetResourceGroup("test-group")
+		require.Error(t, err)
+		require.Nil(t, group)
+		return
+	}
+
+	// Step 1: build a controller in Starter mode so default options include
+	// degraded RU settings.
+	require.NoError(t, deploymode.Set(deploymode.Starter))
 	controllerWithFallback, err := rmclient.NewResourceGroupController(
 		ctx,
 		1,
@@ -110,6 +148,8 @@ func TestResourceGroupsControllerOptionsProvideDegradedFallback(t *testing.T) {
 		require.NoError(t, controllerWithFallback.Stop())
 	}()
 
+	// Step 2: when loading the group fails, Starter should synthesize a degraded
+	// fallback group instead of returning the provider error.
 	group, err := controllerWithFallback.GetResourceGroup("test-group")
 	require.NoError(t, err)
 	require.Equal(t, &rmpb.ResourceGroup{
@@ -118,7 +158,9 @@ func TestResourceGroupsControllerOptionsProvideDegradedFallback(t *testing.T) {
 		RUSettings: newDefaultDegradedRUSettings(),
 	}, group)
 
-	versioninfo.TiDBEdition = versioninfo.CommunityEdition
+	// Step 3: rebuild the controller as a non-Starter edition with the same
+	// provider, so the only behavior change is the edition-gated option.
+	require.NoError(t, deploymode.Set(deploymode.Premium))
 	controllerWithoutFallback, err := rmclient.NewResourceGroupController(
 		ctx,
 		2,
@@ -133,6 +175,8 @@ func TestResourceGroupsControllerOptionsProvideDegradedFallback(t *testing.T) {
 		require.NoError(t, controllerWithoutFallback.Stop())
 	}()
 
+	// Step 4: non-Starter editions must not install degraded RU fallback, so the
+	// provider error is returned and no group is synthesized.
 	group, err = controllerWithoutFallback.GetResourceGroup("test-group")
 	require.Error(t, err)
 	require.Nil(t, group)

From 25cacf46f06ae5999a3bf6c6db43b997f8997c5a Mon Sep 17 00:00:00 2001
From: ystaticy <y_static_y@sina.com>
Date: Fri, 10 Jul 2026 17:27:11 +0800
Subject: [PATCH 05/21]  fix error

Signed-off-by: ystaticy <y_static_y@sina.com>
---
 pkg/domain/BUILD.bazel                     |   8 +-
 pkg/domain/resource_group_provider.go      | 117 ++++++++++++++++
 pkg/domain/resource_group_provider_test.go |  92 +++++++++++++
 pkg/domain/runaway.go                      |   7 +-
 pkg/domain/runaway_test.go                 | 147 ++++++++++++++++-----
 5 files changed, 333 insertions(+), 38 deletions(-)
 create mode 100644 pkg/domain/resource_group_provider.go
 create mode 100644 pkg/domain/resource_group_provider_test.go

diff --git a/pkg/domain/BUILD.bazel b/pkg/domain/BUILD.bazel
index f008e43432cb8..d625af6d5df72 100644
--- a/pkg/domain/BUILD.bazel
+++ b/pkg/domain/BUILD.bazel
@@ -12,6 +12,7 @@ go_library(
         "plan_replayer.go",
         "plan_replayer_dump.go",
         "ru_stats.go",
+        "resource_group_provider.go",
         "runaway.go",
         "schema_checker.go",
         "sysvar_cache.go",
@@ -123,6 +124,7 @@ go_library(
         "@com_github_tikv_client_go_v2//tikv",
         "@com_github_tikv_client_go_v2//txnkv/transaction",
         "@com_github_tikv_pd_client//:client",
+        "@com_github_tikv_pd_client//errs",
         "@com_github_tikv_pd_client//constants",
         "@com_github_tikv_pd_client//http",
         "@com_github_tikv_pd_client//opt",
@@ -150,13 +152,14 @@ go_test(
         "plan_replayer_slow_log_test.go",
         "plan_replayer_test.go",
         "ru_stats_test.go",
+        "resource_group_provider_test.go",
         "runaway_test.go",
         "schema_checker_test.go",
         "topn_slow_query_test.go",
     ],
     embed = [":domain"],
     flaky = True,
-    shard_count = 31,
+    shard_count = 34,
     deps = [
         "//pkg/config",
         "//pkg/config/deploymode",
@@ -178,6 +181,7 @@ go_test(
         "//pkg/parser/mysql",
         "//pkg/parser/terror",
         "//pkg/planner/extstore",
+        "//pkg/resourcegroup/runaway",
         "//pkg/server",
         "//pkg/session",
         "//pkg/sessionctx/vardef",
@@ -200,8 +204,10 @@ go_test(
         "@com_github_pingcap_kvproto//pkg/resource_manager",
         "@com_github_prometheus_client_model//go",
         "@com_github_stretchr_testify//require",
+        "@com_github_tikv_client_go_v2//tikvrpc",
         "@com_github_tikv_client_go_v2//txnkv/transaction",
         "@com_github_tikv_pd_client//:client",
+        "@com_github_tikv_pd_client//errs",
         "@com_github_tikv_pd_client//opt",
         "@com_github_tikv_pd_client//resource_group/controller",
         "@io_etcd_go_etcd_tests_v3//integration",
diff --git a/pkg/domain/resource_group_provider.go b/pkg/domain/resource_group_provider.go
new file mode 100644
index 0000000000000..1b9135c471ff3
--- /dev/null
+++ b/pkg/domain/resource_group_provider.go
@@ -0,0 +1,117 @@
+// Copyright 2026 PingCAP, Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package domain
+
+import (
+	"context"
+	stderrors "errors"
+	"strings"
+
+	rmpb "github.com/pingcap/kvproto/pkg/resource_manager"
+	"github.com/pingcap/errors"
+	pd "github.com/tikv/pd/client"
+	pderr "github.com/tikv/pd/client/errs"
+	rmclient "github.com/tikv/pd/client/resource_group/controller"
+)
+
+// starterResourceGroupProvider wraps a resource group provider and synthesizes
+// degraded resource groups only when resource-manager lookup fails due to
+// unavailability.
+type starterResourceGroupProvider struct {
+	rmclient.ResourceGroupProvider
+	degradedRUSettings *rmpb.GroupRequestUnitSettings
+}
+
+func newStarterResourceGroupProvider(provider rmclient.ResourceGroupProvider) *starterResourceGroupProvider {
+	return &starterResourceGroupProvider{
+		ResourceGroupProvider: provider,
+		degradedRUSettings:      newDefaultDegradedRUSettings(),
+	}
+}
+
+func (p *starterResourceGroupProvider) GetResourceGroup(
+	ctx context.Context, resourceGroupName string, opts ...pd.GetResourceGroupOption,
+) (*rmpb.ResourceGroup, error) {
+	if err := ctx.Err(); err != nil {
+		return nil, err
+	}
+	group, err := p.ResourceGroupProvider.GetResourceGroup(ctx, resourceGroupName, opts...)
+	if err == nil {
+		return group, nil
+	}
+	if !shouldUseDegradedResourceGroupFallback(ctx, err) {
+		return nil, err
+	}
+	return newDegradedResourceGroup(resourceGroupName, p.degradedRUSettings), nil
+}
+
+func newDegradedResourceGroup(name string, ruSettings *rmpb.GroupRequestUnitSettings) *rmpb.ResourceGroup {
+	return &rmpb.ResourceGroup{
+		Name:       name,
+		Mode:       rmpb.GroupMode_RUMode,
+		RUSettings: ruSettings,
+	}
+}
+
+func shouldUseDegradedResourceGroupFallback(ctx context.Context, err error) bool {
+	if err == nil {
+		return false
+	}
+	if ctx.Err() != nil {
+		return false
+	}
+	if stderrors.Is(err, context.Canceled) || stderrors.Is(err, context.DeadlineExceeded) {
+		return false
+	}
+	if isResourceGroupNotExistError(err) {
+		return false
+	}
+	if errors.Is(err, pderr.ErrClientResourceGroupConfigUnavailable) {
+		return true
+	}
+	var getRGErr *pderr.ErrClientGetResourceGroup
+	if errors.As(err, &getRGErr) {
+		return isResourceManagerUnavailableCause(getRGErr.Cause)
+	}
+	return isResourceManagerUnavailableCause(err.Error())
+}
+
+func isResourceGroupNotExistError(err error) bool {
+	var getRGErr *pderr.ErrClientGetResourceGroup
+	if !errors.As(err, &getRGErr) {
+		return false
+	}
+	return isResourceGroupNotExistCause(getRGErr.Cause)
+}
+
+func isResourceGroupNotExistCause(cause string) bool {
+	lower := strings.ToLower(cause)
+	return strings.Contains(lower, "does not exist") ||
+		strings.Contains(lower, "not found") ||
+		strings.Contains(lower, "not exist")
+}
+
+func isResourceManagerUnavailableCause(cause string) bool {
+	if isResourceGroupNotExistCause(cause) {
+		return false
+	}
+	lower := strings.ToLower(cause)
+	return strings.Contains(lower, "unavailable") ||
+		strings.Contains(lower, "connection refused") ||
+		strings.Contains(lower, "connection reset") ||
+		strings.Contains(lower, "deadline exceeded") ||
+		strings.Contains(lower, "transport is closing") ||
+		strings.Contains(lower, "rpc error")
+}
diff --git a/pkg/domain/resource_group_provider_test.go b/pkg/domain/resource_group_provider_test.go
new file mode 100644
index 0000000000000..1f75de1da8ba7
--- /dev/null
+++ b/pkg/domain/resource_group_provider_test.go
@@ -0,0 +1,92 @@
+// Copyright 2026 PingCAP, Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package domain
+
+import (
+	"context"
+	"errors"
+	"testing"
+
+	"github.com/stretchr/testify/require"
+	pderr "github.com/tikv/pd/client/errs"
+)
+
+func TestShouldUseDegradedResourceGroupFallback(t *testing.T) {
+	t.Parallel()
+
+	ctx := context.Background()
+	canceledCtx, cancel := context.WithCancel(context.Background())
+	cancel()
+
+	tests := []struct {
+		name string
+		ctx  context.Context
+		err  error
+		want bool
+	}{
+		{
+			name: "resource manager unavailable",
+			ctx:  ctx,
+			err: &pderr.ErrClientGetResourceGroup{
+				ResourceGroupName: "rg1",
+				Cause:             "resource group unavailable",
+			},
+			want: true,
+		},
+		{
+			name: "resource group not found",
+			ctx:  ctx,
+			err: &pderr.ErrClientGetResourceGroup{
+				ResourceGroupName: "rg1",
+				Cause:             "resource group does not exist",
+			},
+			want: false,
+		},
+		{
+			name: "context canceled",
+			ctx:  canceledCtx,
+			err: &pderr.ErrClientGetResourceGroup{
+				ResourceGroupName: "rg1",
+				Cause:             "resource group unavailable",
+			},
+			want: false,
+		},
+		{
+			name: "lookup canceled",
+			ctx:  ctx,
+			err:  context.Canceled,
+			want: false,
+		},
+		{
+			name: "config unavailable",
+			ctx:  ctx,
+			err:  pderr.ErrClientResourceGroupConfigUnavailable.FastGenByArgs("not configured"),
+			want: true,
+		},
+		{
+			name: "generic non retryable",
+			ctx:  ctx,
+			err:  errors.New("invalid resource group lookup"),
+			want: false,
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			t.Parallel()
+			require.Equal(t, tt.want, shouldUseDegradedResourceGroupFallback(tt.ctx, tt.err))
+		})
+	}
+}
diff --git a/pkg/domain/runaway.go b/pkg/domain/runaway.go
index 486c38ac7c53d..fbbb011c864e7 100644
--- a/pkg/domain/runaway.go
+++ b/pkg/domain/runaway.go
@@ -59,7 +59,6 @@ func newResourceGroupsControllerOptions() []rmclient.ResourceControlCreateOption
 	if deploymode.IsStarter() {
 		opts = append(opts,
 			rmclient.WithDegradedModeWaitDuration(defaultDegradedModeWaitTimeout),
-			rmclient.WithDegradedRUSettings(newDefaultDegradedRUSettings()),
 		)
 	}
 	if strings.Contains(os.Getenv("NAMESPACE"), "vip") {
@@ -82,7 +81,11 @@ func (do *Domain) initResourceGroupsController(ctx context.Context, pdClient pd.
 	if codec := do.Store().GetCodec(); codec != nil {
 		keyspaceID = uint32(codec.GetKeyspaceID())
 	}
-	control, err := rmclient.NewResourceGroupController(ctx, uniqueID, pdClient, nil, keyspaceID, newResourceGroupsControllerOptions()...)
+	var provider rmclient.ResourceGroupProvider = pdClient
+	if deploymode.IsStarter() {
+		provider = newStarterResourceGroupProvider(pdClient)
+	}
+	control, err := rmclient.NewResourceGroupController(ctx, uniqueID, provider, nil, keyspaceID, newResourceGroupsControllerOptions()...)
 	if err != nil {
 		return err
 	}
diff --git a/pkg/domain/runaway_test.go b/pkg/domain/runaway_test.go
index cebd66530a5cf..19ad5b2f557c0 100644
--- a/pkg/domain/runaway_test.go
+++ b/pkg/domain/runaway_test.go
@@ -18,13 +18,17 @@ import (
 	"context"
 	"errors"
 	"testing"
+	"time"
 
 	"github.com/pingcap/kvproto/pkg/meta_storagepb"
 	rmpb "github.com/pingcap/kvproto/pkg/resource_manager"
 	"github.com/pingcap/tidb/pkg/config/deploymode"
 	"github.com/pingcap/tidb/pkg/config/kerneltype"
+	"github.com/pingcap/tidb/pkg/resourcegroup/runaway"
 	"github.com/stretchr/testify/require"
+	"github.com/tikv/client-go/v2/tikvrpc"
 	pd "github.com/tikv/pd/client"
+	pderr "github.com/tikv/pd/client/errs"
 	"github.com/tikv/pd/client/opt"
 	rmclient "github.com/tikv/pd/client/resource_group/controller"
 )
@@ -79,6 +83,28 @@ func (s *resourceGroupProviderStub) Put(context.Context, []byte, []byte, ...opt.
 	return &meta_storagepb.PutResponse{Header: &meta_storagepb.ResponseHeader{}}, nil
 }
 
+func newStarterControllerForTest(t *testing.T, provider rmclient.ResourceGroupProvider) *rmclient.ResourceGroupsController {
+	t.Helper()
+	ctx, cancel := context.WithCancel(context.Background())
+	t.Cleanup(cancel)
+
+	require.NoError(t, deploymode.Set(deploymode.Starter))
+	controller, err := rmclient.NewResourceGroupController(
+		ctx,
+		1,
+		newStarterResourceGroupProvider(provider),
+		nil,
+		0,
+		newResourceGroupsControllerOptions()...,
+	)
+	require.NoError(t, err)
+	controller.Start(ctx)
+	t.Cleanup(func() {
+		require.NoError(t, controller.Stop())
+	})
+	return controller
+}
+
 func TestResourceGroupsControllerOptionsProvideDegradedFallback(t *testing.T) {
 	if kerneltype.IsNextGen() {
 		// Preserve the process-wide deploy mode because deploymode.IsStarter reads
@@ -89,12 +115,9 @@ func TestResourceGroupsControllerOptionsProvideDegradedFallback(t *testing.T) {
 		})
 	}
 
-	// Use one cancelable context for the short-lived controllers created below.
 	ctx, cancel := context.WithCancel(context.Background())
 	defer cancel()
 
-	// Return a normal resource group together with an error. The error path is
-	// what should trigger the degraded RU fallback in Starter mode.
 	provider := &resourceGroupProviderStub{
 		resourceGroup: &rmpb.ResourceGroup{
 			Name: "test-group",
@@ -105,12 +128,13 @@ func TestResourceGroupsControllerOptionsProvideDegradedFallback(t *testing.T) {
 				},
 			},
 		},
-		resourceErr: errors.New("resource group unavailable"),
+		resourceErr: &pderr.ErrClientGetResourceGroup{
+			ResourceGroupName: "test-group",
+			Cause:             "resource group unavailable",
+		},
 	}
 
 	if !kerneltype.IsNextGen() {
-		// In classic builds deploymode.IsStarter is always false. This still guards
-		// against accidentally enabling degraded fallback outside NextGen Starter.
 		controller, err := rmclient.NewResourceGroupController(
 			ctx,
 			1,
@@ -131,35 +155,11 @@ func TestResourceGroupsControllerOptionsProvideDegradedFallback(t *testing.T) {
 		return
 	}
 
-	// Step 1: build a controller in Starter mode so default options include
-	// degraded RU settings.
-	require.NoError(t, deploymode.Set(deploymode.Starter))
-	controllerWithFallback, err := rmclient.NewResourceGroupController(
-		ctx,
-		1,
-		provider,
-		nil,
-		0,
-		newResourceGroupsControllerOptions()...,
-	)
-	require.NoError(t, err)
-	controllerWithFallback.Start(ctx)
-	defer func() {
-		require.NoError(t, controllerWithFallback.Stop())
-	}()
-
-	// Step 2: when loading the group fails, Starter should synthesize a degraded
-	// fallback group instead of returning the provider error.
+	controllerWithFallback := newStarterControllerForTest(t, provider)
 	group, err := controllerWithFallback.GetResourceGroup("test-group")
 	require.NoError(t, err)
-	require.Equal(t, &rmpb.ResourceGroup{
-		Name:       "test-group",
-		Mode:       rmpb.GroupMode_RUMode,
-		RUSettings: newDefaultDegradedRUSettings(),
-	}, group)
-
-	// Step 3: rebuild the controller as a non-Starter edition with the same
-	// provider, so the only behavior change is the edition-gated option.
+	require.Equal(t, newDegradedResourceGroup("test-group", newDefaultDegradedRUSettings()), group)
+
 	require.NoError(t, deploymode.Set(deploymode.Premium))
 	controllerWithoutFallback, err := rmclient.NewResourceGroupController(
 		ctx,
@@ -175,9 +175,86 @@ func TestResourceGroupsControllerOptionsProvideDegradedFallback(t *testing.T) {
 		require.NoError(t, controllerWithoutFallback.Stop())
 	}()
 
-	// Step 4: non-Starter editions must not install degraded RU fallback, so the
-	// provider error is returned and no group is synthesized.
 	group, err = controllerWithoutFallback.GetResourceGroup("test-group")
 	require.Error(t, err)
 	require.Nil(t, group)
 }
+
+func TestStarterResourceGroupProviderNonRetryableErrors(t *testing.T) {
+	if !kerneltype.IsNextGen() {
+		t.Skip("Starter deploy mode is only available in NextGen builds")
+	}
+	originalDeployMode := deploymode.Get()
+	t.Cleanup(func() {
+		require.NoError(t, deploymode.Set(originalDeployMode))
+	})
+
+	t.Run("NotFound", func(t *testing.T) {
+		provider := &resourceGroupProviderStub{
+			resourceErr: rmclient.NewResourceGroupNotExistErr("missing-group"),
+		}
+		controller := newStarterControllerForTest(t, provider)
+
+		group, err := controller.GetResourceGroup("missing-group")
+		require.Error(t, err)
+		require.Nil(t, group)
+	})
+
+	t.Run("ContextCanceled", func(t *testing.T) {
+		ctx, cancel := context.WithCancel(context.Background())
+		cancel()
+
+		provider := &resourceGroupProviderStub{
+			resourceErr: context.Canceled,
+		}
+		wrapped := newStarterResourceGroupProvider(provider)
+		group, err := wrapped.GetResourceGroup(ctx, "test-group")
+		require.ErrorIs(t, err, context.Canceled)
+		require.Nil(t, group)
+	})
+
+	t.Run("GenericNonRetryableError", func(t *testing.T) {
+		provider := &resourceGroupProviderStub{
+			resourceErr: errors.New("invalid resource group lookup"),
+		}
+		controller := newStarterControllerForTest(t, provider)
+
+		group, err := controller.GetResourceGroup("test-group")
+		require.Error(t, err)
+		require.Nil(t, group)
+	})
+}
+
+func TestStarterSwitchGroupRejectsMissingGroup(t *testing.T) {
+	if !kerneltype.IsNextGen() {
+		t.Skip("Starter deploy mode is only available in NextGen builds")
+	}
+	originalDeployMode := deploymode.Get()
+	t.Cleanup(func() {
+		require.NoError(t, deploymode.Set(originalDeployMode))
+	})
+
+	provider := &resourceGroupProviderStub{
+		resourceErr: rmclient.NewResourceGroupNotExistErr("missing-switch-group"),
+	}
+	controller := newStarterControllerForTest(t, provider)
+	manager := runaway.NewRunawayManager(controller, "127.0.0.1:4000", nil, make(chan struct{}), nil, nil)
+	checker := runaway.NewChecker(
+		manager,
+		"source-group",
+		&rmpb.RunawaySettings{
+			Action:          rmpb.RunawayAction_SwitchGroup,
+			SwitchGroupName: "missing-switch-group",
+			Rule:            &rmpb.RunawayRule{ProcessedKeys: 1},
+		},
+		"SELECT 1",
+		"sql_digest",
+		"plan_digest",
+		time.Now(),
+	)
+
+	require.NoError(t, checker.CheckThresholds(nil, 10, nil))
+	req := &tikvrpc.Request{}
+	require.NoError(t, checker.BeforeCopRequest(req))
+	require.Empty(t, req.ResourceControlContext.ResourceGroupName)
+}

From 29ff847779ecb0e8c4209cf58f7b26502326ec93 Mon Sep 17 00:00:00 2001
From: ystaticy <y_static_y@sina.com>
Date: Mon, 13 Jul 2026 15:49:19 +0800
Subject: [PATCH 06/21]  fix comments

Signed-off-by: ystaticy <y_static_y@sina.com>
---
 cmd/tidb-server/main.go               |  5 +++++
 cmd/tidb-server/main_test.go          |  2 ++
 pkg/config/config.go                  |  3 +++
 pkg/domain/BUILD.bazel                |  8 ++++----
 pkg/domain/resource_group_provider.go |  9 ++++-----
 pkg/domain/runaway.go                 |  4 ++--
 pkg/domain/runaway_test.go            | 21 +++++++++++++++++++++
 7 files changed, 41 insertions(+), 11 deletions(-)

diff --git a/cmd/tidb-server/main.go b/cmd/tidb-server/main.go
index e117e3e138629..516971d745e07 100644
--- a/cmd/tidb-server/main.go
+++ b/cmd/tidb-server/main.go
@@ -710,6 +710,11 @@ func overrideConfig(cfg *config.Config, fset *flag.FlagSet) {
 	fset.Visit(func(f *flag.Flag) {
 		actualFlags[f.Name] = true
 	})
+	if actualFlags[nmStarterParams] && cfg.DeployMode == deploymode.Starter {
+		params, err := parseStarterAdditionalParams(getStarterAdditionalParams())
+		terror.MustNil(err)
+		cfg.StarterParams.PodNamespace = params.podNamespace
+	}
 
 	// Base
 	if actualFlags[nmHost] {
diff --git a/cmd/tidb-server/main_test.go b/cmd/tidb-server/main_test.go
index 5808ccc14bdf9..9650261a94e54 100644
--- a/cmd/tidb-server/main_test.go
+++ b/cmd/tidb-server/main_test.go
@@ -89,8 +89,10 @@ func TestOverrideConfigKeyspaceActivateMode(t *testing.T) {
 	}))
 
 	cfg := config.NewConfig()
+	cfg.DeployMode = deploymode.Starter
 	overrideConfig(cfg, fset)
 	require.True(t, cfg.KeyspaceActivateMode)
+	require.Equal(t, "ns-1", cfg.StarterParams.PodNamespace)
 	require.Equal(t, "pod-name=pod-1,pod-ip=10.0.0.1,pod-namespace=ns-1", *starterAdditionalParams)
 }
 
diff --git a/pkg/config/config.go b/pkg/config/config.go
index a7cbf232abf5f..32a61be17b6f0 100644
--- a/pkg/config/config.go
+++ b/pkg/config/config.go
@@ -1094,6 +1094,9 @@ type StarterParams struct {
 	// ManagerAddr is the TiDB manager address used by the shutdown notifier.
 	// When empty and EnableManagerNotifier is true, the Starter path derives the service address from starter additional params.
 	ManagerAddr string `toml:"manager-addr" json:"manager-addr,omitempty"`
+	// PodNamespace captures the runtime pod namespace from --starter-additional-params.
+	// It is command-line derived runtime metadata rather than file-backed config.
+	PodNamespace string `toml:"-" json:"-"`
 	// MaxImportDataSize is the maximum total real source data size allowed for IMPORT INTO.
 	// Zero means unlimited.
 	MaxImportDataSize configtypes.ByteSize `toml:"max-import-data-size" json:"max-import-data-size,omitempty"`
diff --git a/pkg/domain/BUILD.bazel b/pkg/domain/BUILD.bazel
index d625af6d5df72..7cf5bf7b3f08e 100644
--- a/pkg/domain/BUILD.bazel
+++ b/pkg/domain/BUILD.bazel
@@ -11,8 +11,8 @@ go_library(
         "optimize_trace.go",
         "plan_replayer.go",
         "plan_replayer_dump.go",
-        "ru_stats.go",
         "resource_group_provider.go",
+        "ru_stats.go",
         "runaway.go",
         "schema_checker.go",
         "sysvar_cache.go",
@@ -124,8 +124,8 @@ go_library(
         "@com_github_tikv_client_go_v2//tikv",
         "@com_github_tikv_client_go_v2//txnkv/transaction",
         "@com_github_tikv_pd_client//:client",
-        "@com_github_tikv_pd_client//errs",
         "@com_github_tikv_pd_client//constants",
+        "@com_github_tikv_pd_client//errs",
         "@com_github_tikv_pd_client//http",
         "@com_github_tikv_pd_client//opt",
         "@com_github_tikv_pd_client//pkg/caller",
@@ -151,15 +151,15 @@ go_test(
         "plan_replayer_handle_test.go",
         "plan_replayer_slow_log_test.go",
         "plan_replayer_test.go",
-        "ru_stats_test.go",
         "resource_group_provider_test.go",
+        "ru_stats_test.go",
         "runaway_test.go",
         "schema_checker_test.go",
         "topn_slow_query_test.go",
     ],
     embed = [":domain"],
     flaky = True,
-    shard_count = 34,
+    shard_count = 35,
     deps = [
         "//pkg/config",
         "//pkg/config/deploymode",
diff --git a/pkg/domain/resource_group_provider.go b/pkg/domain/resource_group_provider.go
index 1b9135c471ff3..91d5c1570acd8 100644
--- a/pkg/domain/resource_group_provider.go
+++ b/pkg/domain/resource_group_provider.go
@@ -20,7 +20,6 @@ import (
 	"strings"
 
 	rmpb "github.com/pingcap/kvproto/pkg/resource_manager"
-	"github.com/pingcap/errors"
 	pd "github.com/tikv/pd/client"
 	pderr "github.com/tikv/pd/client/errs"
 	rmclient "github.com/tikv/pd/client/resource_group/controller"
@@ -37,7 +36,7 @@ type starterResourceGroupProvider struct {
 func newStarterResourceGroupProvider(provider rmclient.ResourceGroupProvider) *starterResourceGroupProvider {
 	return &starterResourceGroupProvider{
 		ResourceGroupProvider: provider,
-		degradedRUSettings:      newDefaultDegradedRUSettings(),
+		degradedRUSettings:    newDefaultDegradedRUSettings(),
 	}
 }
 
@@ -78,11 +77,11 @@ func shouldUseDegradedResourceGroupFallback(ctx context.Context, err error) bool
 	if isResourceGroupNotExistError(err) {
 		return false
 	}
-	if errors.Is(err, pderr.ErrClientResourceGroupConfigUnavailable) {
+	if stderrors.Is(err, pderr.ErrClientResourceGroupConfigUnavailable) {
 		return true
 	}
 	var getRGErr *pderr.ErrClientGetResourceGroup
-	if errors.As(err, &getRGErr) {
+	if stderrors.As(err, &getRGErr) {
 		return isResourceManagerUnavailableCause(getRGErr.Cause)
 	}
 	return isResourceManagerUnavailableCause(err.Error())
@@ -90,7 +89,7 @@ func shouldUseDegradedResourceGroupFallback(ctx context.Context, err error) bool
 
 func isResourceGroupNotExistError(err error) bool {
 	var getRGErr *pderr.ErrClientGetResourceGroup
-	if !errors.As(err, &getRGErr) {
+	if !stderrors.As(err, &getRGErr) {
 		return false
 	}
 	return isResourceGroupNotExistCause(getRGErr.Cause)
diff --git a/pkg/domain/runaway.go b/pkg/domain/runaway.go
index fbbb011c864e7..4f6cc7710a39a 100644
--- a/pkg/domain/runaway.go
+++ b/pkg/domain/runaway.go
@@ -17,12 +17,12 @@ package domain
 import (
 	"context"
 	"net"
-	"os"
 	"strconv"
 	"strings"
 	"time"
 
 	rmpb "github.com/pingcap/kvproto/pkg/resource_manager"
+	"github.com/pingcap/tidb/pkg/config"
 	"github.com/pingcap/tidb/pkg/config/deploymode"
 	"github.com/pingcap/tidb/pkg/domain/infosync"
 	"github.com/pingcap/tidb/pkg/resourcegroup/runaway"
@@ -61,7 +61,7 @@ func newResourceGroupsControllerOptions() []rmclient.ResourceControlCreateOption
 			rmclient.WithDegradedModeWaitDuration(defaultDegradedModeWaitTimeout),
 		)
 	}
-	if strings.Contains(os.Getenv("NAMESPACE"), "vip") {
+	if strings.Contains(config.GetGlobalConfig().StarterParams.PodNamespace, "vip") {
 		opts = append(opts,
 			rmclient.WithWaitRetryInterval(tokenWaitRetryInterval),
 			rmclient.WithWaitRetryTimes(tokenWaitRetryTimes),
diff --git a/pkg/domain/runaway_test.go b/pkg/domain/runaway_test.go
index 19ad5b2f557c0..365168233af50 100644
--- a/pkg/domain/runaway_test.go
+++ b/pkg/domain/runaway_test.go
@@ -22,6 +22,7 @@ import (
 
 	"github.com/pingcap/kvproto/pkg/meta_storagepb"
 	rmpb "github.com/pingcap/kvproto/pkg/resource_manager"
+	"github.com/pingcap/tidb/pkg/config"
 	"github.com/pingcap/tidb/pkg/config/deploymode"
 	"github.com/pingcap/tidb/pkg/config/kerneltype"
 	"github.com/pingcap/tidb/pkg/resourcegroup/runaway"
@@ -258,3 +259,23 @@ func TestStarterSwitchGroupRejectsMissingGroup(t *testing.T) {
 	require.NoError(t, checker.BeforeCopRequest(req))
 	require.Empty(t, req.ResourceControlContext.ResourceGroupName)
 }
+
+func TestResourceGroupsControllerOptionsUseStarterPodNamespaceForVIPWaitRetry(t *testing.T) {
+	restoreConfig := config.RestoreFunc()
+	t.Cleanup(restoreConfig)
+	originalDeployMode := deploymode.Get()
+	t.Cleanup(func() {
+		require.NoError(t, deploymode.Set(originalDeployMode))
+	})
+	require.NoError(t, deploymode.Set(deploymode.Starter))
+
+	config.UpdateGlobal(func(conf *config.Config) {
+		conf.StarterParams.PodNamespace = "starter-vip-ns"
+	})
+	require.Len(t, newResourceGroupsControllerOptions(), 4)
+
+	config.UpdateGlobal(func(conf *config.Config) {
+		conf.StarterParams.PodNamespace = "starter-standard-ns"
+	})
+	require.Len(t, newResourceGroupsControllerOptions(), 2)
+}

From 8054a7f59251471ddf120722940c905a599a9c2f Mon Sep 17 00:00:00 2001
From: ystaticy <y_static_y@sina.com>
Date: Mon, 13 Jul 2026 17:30:22 +0800
Subject: [PATCH 07/21]  fix comments

Signed-off-by: ystaticy <y_static_y@sina.com>
---
 pkg/domain/resource_group_provider_test.go | 3 ---
 1 file changed, 3 deletions(-)

diff --git a/pkg/domain/resource_group_provider_test.go b/pkg/domain/resource_group_provider_test.go
index 1f75de1da8ba7..d51dcdd73bc96 100644
--- a/pkg/domain/resource_group_provider_test.go
+++ b/pkg/domain/resource_group_provider_test.go
@@ -24,8 +24,6 @@ import (
 )
 
 func TestShouldUseDegradedResourceGroupFallback(t *testing.T) {
-	t.Parallel()
-
 	ctx := context.Background()
 	canceledCtx, cancel := context.WithCancel(context.Background())
 	cancel()
@@ -85,7 +83,6 @@ func TestShouldUseDegradedResourceGroupFallback(t *testing.T) {
 
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {
-			t.Parallel()
 			require.Equal(t, tt.want, shouldUseDegradedResourceGroupFallback(tt.ctx, tt.err))
 		})
 	}

From 0c6d89dea1e2bc402bb0ceeea690360d2f37d0d6 Mon Sep 17 00:00:00 2001
From: ystaticy <y_static_y@sina.com>
Date: Tue, 14 Jul 2026 10:20:55 +0800
Subject: [PATCH 08/21]  fix build

Signed-off-by: ystaticy <y_static_y@sina.com>
---
 pkg/domain/BUILD.bazel     | 1 +
 pkg/domain/runaway_test.go | 5 +++--
 2 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/pkg/domain/BUILD.bazel b/pkg/domain/BUILD.bazel
index 7cf5bf7b3f08e..1c1be2dd6b8d0 100644
--- a/pkg/domain/BUILD.bazel
+++ b/pkg/domain/BUILD.bazel
@@ -207,6 +207,7 @@ go_test(
         "@com_github_tikv_client_go_v2//tikvrpc",
         "@com_github_tikv_client_go_v2//txnkv/transaction",
         "@com_github_tikv_pd_client//:client",
+        "@com_github_tikv_pd_client//clients/metastorage",
         "@com_github_tikv_pd_client//errs",
         "@com_github_tikv_pd_client//opt",
         "@com_github_tikv_pd_client//resource_group/controller",
diff --git a/pkg/domain/runaway_test.go b/pkg/domain/runaway_test.go
index 365168233af50..f63cae4234fe1 100644
--- a/pkg/domain/runaway_test.go
+++ b/pkg/domain/runaway_test.go
@@ -29,6 +29,7 @@ import (
 	"github.com/stretchr/testify/require"
 	"github.com/tikv/client-go/v2/tikvrpc"
 	pd "github.com/tikv/pd/client"
+	"github.com/tikv/pd/client/clients/metastorage"
 	pderr "github.com/tikv/pd/client/errs"
 	"github.com/tikv/pd/client/opt"
 	rmclient "github.com/tikv/pd/client/resource_group/controller"
@@ -72,8 +73,8 @@ func (s *resourceGroupProviderStub) LoadResourceGroups(context.Context) ([]*rmpb
 	return nil, 0, nil
 }
 
-func (s *resourceGroupProviderStub) Watch(context.Context, []byte, ...opt.MetaStorageOption) (chan []*meta_storagepb.Event, error) {
-	return make(chan []*meta_storagepb.Event), nil
+func (s *resourceGroupProviderStub) Watch(context.Context, []byte, ...opt.MetaStorageOption) (chan *metastorage.WatchResponse, error) {
+	return make(chan *metastorage.WatchResponse), nil
 }
 
 func (s *resourceGroupProviderStub) Get(context.Context, []byte, ...opt.MetaStorageOption) (*meta_storagepb.GetResponse, error) {

From 73f9e5abec81dd1349243ab6e916035719f58480 Mon Sep 17 00:00:00 2001
From: ystaticy <y_static_y@sina.com>
Date: Tue, 14 Jul 2026 11:10:19 +0800
Subject: [PATCH 09/21]  fix ut

Signed-off-by: ystaticy <y_static_y@sina.com>
---
 pkg/domain/runaway_test.go | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/pkg/domain/runaway_test.go b/pkg/domain/runaway_test.go
index f63cae4234fe1..1deec47293744 100644
--- a/pkg/domain/runaway_test.go
+++ b/pkg/domain/runaway_test.go
@@ -40,6 +40,8 @@ type resourceGroupProviderStub struct {
 	resourceErr   error
 }
 
+var _ metastorage.Client = (*resourceGroupProviderStub)(nil)
+
 // GetResourceGroup returns both the mocked resource group and the mocked error.
 // This lets the test verify whether the controller uses the degraded fallback
 // only for the editions that enable it.
@@ -73,8 +75,8 @@ func (s *resourceGroupProviderStub) LoadResourceGroups(context.Context) ([]*rmpb
 	return nil, 0, nil
 }
 
-func (s *resourceGroupProviderStub) Watch(context.Context, []byte, ...opt.MetaStorageOption) (chan *metastorage.WatchResponse, error) {
-	return make(chan *metastorage.WatchResponse), nil
+func (s *resourceGroupProviderStub) Watch(context.Context, []byte, ...opt.MetaStorageOption) (chan []*meta_storagepb.Event, error) {
+	return make(chan []*meta_storagepb.Event), nil
 }
 
 func (s *resourceGroupProviderStub) Get(context.Context, []byte, ...opt.MetaStorageOption) (*meta_storagepb.GetResponse, error) {
@@ -241,6 +243,7 @@ func TestStarterSwitchGroupRejectsMissingGroup(t *testing.T) {
 	}
 	controller := newStarterControllerForTest(t, provider)
 	manager := runaway.NewRunawayManager(controller, "127.0.0.1:4000", nil, make(chan struct{}), nil, nil)
+	t.Cleanup(manager.Stop)
 	checker := runaway.NewChecker(
 		manager,
 		"source-group",
@@ -258,7 +261,7 @@ func TestStarterSwitchGroupRejectsMissingGroup(t *testing.T) {
 	require.NoError(t, checker.CheckThresholds(nil, 10, nil))
 	req := &tikvrpc.Request{}
 	require.NoError(t, checker.BeforeCopRequest(req))
-	require.Empty(t, req.ResourceControlContext.ResourceGroupName)
+	require.Empty(t, req.GetResourceControlContext().GetResourceGroupName())
 }
 
 func TestResourceGroupsControllerOptionsUseStarterPodNamespaceForVIPWaitRetry(t *testing.T) {

From 636fcd9e0eb8494efa336b4a6b237737820f2323 Mon Sep 17 00:00:00 2001
From: ystaticy <y_static_y@sina.com>
Date: Tue, 14 Jul 2026 14:01:02 +0800
Subject: [PATCH 10/21]  fix build

Signed-off-by: ystaticy <y_static_y@sina.com>
---
 pkg/domain/BUILD.bazel                        |  2 -
 .../infosync/resource_manager_client.go       |  8 ++
 pkg/domain/runaway_test.go                    | 93 ++++++-------------
 pkg/executor/BUILD.bazel                      |  2 -
 pkg/executor/adapter_internal_test.go         | 63 +++----------
 5 files changed, 48 insertions(+), 120 deletions(-)

diff --git a/pkg/domain/BUILD.bazel b/pkg/domain/BUILD.bazel
index 1c1be2dd6b8d0..dc84cdd7d002e 100644
--- a/pkg/domain/BUILD.bazel
+++ b/pkg/domain/BUILD.bazel
@@ -199,7 +199,6 @@ go_test(
         "@com_github_ngaut_pools//:pools",
         "@com_github_pingcap_errors//:errors",
         "@com_github_pingcap_failpoint//:failpoint",
-        "@com_github_pingcap_kvproto//pkg/meta_storagepb",
         "@com_github_pingcap_kvproto//pkg/metapb",
         "@com_github_pingcap_kvproto//pkg/resource_manager",
         "@com_github_prometheus_client_model//go",
@@ -207,7 +206,6 @@ go_test(
         "@com_github_tikv_client_go_v2//tikvrpc",
         "@com_github_tikv_client_go_v2//txnkv/transaction",
         "@com_github_tikv_pd_client//:client",
-        "@com_github_tikv_pd_client//clients/metastorage",
         "@com_github_tikv_pd_client//errs",
         "@com_github_tikv_pd_client//opt",
         "@com_github_tikv_pd_client//resource_group/controller",
diff --git a/pkg/domain/infosync/resource_manager_client.go b/pkg/domain/infosync/resource_manager_client.go
index fbad3d822a948..3f44500b57dbd 100644
--- a/pkg/domain/infosync/resource_manager_client.go
+++ b/pkg/domain/infosync/resource_manager_client.go
@@ -147,6 +147,14 @@ func (*mockResourceManagerClient) LoadResourceGroups(context.Context) ([]*rmpb.R
 	return nil, 0, nil
 }
 
+func (*mockResourceManagerClient) Get(context.Context, []byte, ...opt.MetaStorageOption) (*meta_storagepb.GetResponse, error) {
+	return &meta_storagepb.GetResponse{Header: &meta_storagepb.ResponseHeader{}}, nil
+}
+
+func (*mockResourceManagerClient) Put(context.Context, []byte, []byte, ...opt.MetaStorageOption) (*meta_storagepb.PutResponse, error) {
+	return &meta_storagepb.PutResponse{Header: &meta_storagepb.ResponseHeader{}}, nil
+}
+
 func (m *mockResourceManagerClient) Watch(_ context.Context, key []byte, _ ...opt.MetaStorageOption) (chan []*meta_storagepb.Event, error) {
 	if bytes.Equal(pd.GroupSettingsPathPrefixBytes(m.keyspaceID), key) {
 		return m.eventCh, nil
diff --git a/pkg/domain/runaway_test.go b/pkg/domain/runaway_test.go
index 1deec47293744..3184f44c2ffd3 100644
--- a/pkg/domain/runaway_test.go
+++ b/pkg/domain/runaway_test.go
@@ -20,27 +20,35 @@ import (
 	"testing"
 	"time"
 
-	"github.com/pingcap/kvproto/pkg/meta_storagepb"
 	rmpb "github.com/pingcap/kvproto/pkg/resource_manager"
 	"github.com/pingcap/tidb/pkg/config"
 	"github.com/pingcap/tidb/pkg/config/deploymode"
 	"github.com/pingcap/tidb/pkg/config/kerneltype"
+	"github.com/pingcap/tidb/pkg/domain/infosync"
 	"github.com/pingcap/tidb/pkg/resourcegroup/runaway"
 	"github.com/stretchr/testify/require"
 	"github.com/tikv/client-go/v2/tikvrpc"
 	pd "github.com/tikv/pd/client"
-	"github.com/tikv/pd/client/clients/metastorage"
 	pderr "github.com/tikv/pd/client/errs"
-	"github.com/tikv/pd/client/opt"
 	rmclient "github.com/tikv/pd/client/resource_group/controller"
 )
 
 type resourceGroupProviderStub struct {
+	rmclient.ResourceGroupProvider
 	resourceGroup *rmpb.ResourceGroup
 	resourceErr   error
 }
 
-var _ metastorage.Client = (*resourceGroupProviderStub)(nil)
+func newResourceGroupProviderStub(t *testing.T, resourceGroup *rmpb.ResourceGroup, resourceErr error) *resourceGroupProviderStub {
+	t.Helper()
+	baseProvider, ok := infosync.NewMockResourceManagerClient(0).(rmclient.ResourceGroupProvider)
+	require.True(t, ok)
+	return &resourceGroupProviderStub{
+		ResourceGroupProvider: baseProvider,
+		resourceGroup:         resourceGroup,
+		resourceErr:           resourceErr,
+	}
+}
 
 // GetResourceGroup returns both the mocked resource group and the mocked error.
 // This lets the test verify whether the controller uses the degraded fallback
@@ -49,44 +57,6 @@ func (s *resourceGroupProviderStub) GetResourceGroup(context.Context, string, ..
 	return s.resourceGroup, s.resourceErr
 }
 
-// The remaining methods only satisfy the controller's provider dependencies.
-// The fallback test does not exercise their behavior.
-func (s *resourceGroupProviderStub) ListResourceGroups(context.Context, ...pd.GetResourceGroupOption) ([]*rmpb.ResourceGroup, error) {
-	return nil, nil
-}
-
-func (s *resourceGroupProviderStub) AddResourceGroup(context.Context, *rmpb.ResourceGroup) (string, error) {
-	return "", nil
-}
-
-func (s *resourceGroupProviderStub) ModifyResourceGroup(context.Context, *rmpb.ResourceGroup) (string, error) {
-	return "", nil
-}
-
-func (s *resourceGroupProviderStub) DeleteResourceGroup(context.Context, string) (string, error) {
-	return "", nil
-}
-
-func (s *resourceGroupProviderStub) AcquireTokenBuckets(context.Context, *rmpb.TokenBucketsRequest) ([]*rmpb.TokenBucketResponse, error) {
-	return nil, nil
-}
-
-func (s *resourceGroupProviderStub) LoadResourceGroups(context.Context) ([]*rmpb.ResourceGroup, int64, error) {
-	return nil, 0, nil
-}
-
-func (s *resourceGroupProviderStub) Watch(context.Context, []byte, ...opt.MetaStorageOption) (chan []*meta_storagepb.Event, error) {
-	return make(chan []*meta_storagepb.Event), nil
-}
-
-func (s *resourceGroupProviderStub) Get(context.Context, []byte, ...opt.MetaStorageOption) (*meta_storagepb.GetResponse, error) {
-	return &meta_storagepb.GetResponse{Header: &meta_storagepb.ResponseHeader{}}, nil
-}
-
-func (s *resourceGroupProviderStub) Put(context.Context, []byte, []byte, ...opt.MetaStorageOption) (*meta_storagepb.PutResponse, error) {
-	return &meta_storagepb.PutResponse{Header: &meta_storagepb.ResponseHeader{}}, nil
-}
-
 func newStarterControllerForTest(t *testing.T, provider rmclient.ResourceGroupProvider) *rmclient.ResourceGroupsController {
 	t.Helper()
 	ctx, cancel := context.WithCancel(context.Background())
@@ -122,21 +92,18 @@ func TestResourceGroupsControllerOptionsProvideDegradedFallback(t *testing.T) {
 	ctx, cancel := context.WithCancel(context.Background())
 	defer cancel()
 
-	provider := &resourceGroupProviderStub{
-		resourceGroup: &rmpb.ResourceGroup{
-			Name: "test-group",
-			Mode: rmpb.GroupMode_RUMode,
-			RUSettings: &rmpb.GroupRequestUnitSettings{
-				RU: &rmpb.TokenBucket{
-					Settings: &rmpb.TokenLimitSettings{FillRate: 1},
-				},
+	provider := newResourceGroupProviderStub(t, &rmpb.ResourceGroup{
+		Name: "test-group",
+		Mode: rmpb.GroupMode_RUMode,
+		RUSettings: &rmpb.GroupRequestUnitSettings{
+			RU: &rmpb.TokenBucket{
+				Settings: &rmpb.TokenLimitSettings{FillRate: 1},
 			},
 		},
-		resourceErr: &pderr.ErrClientGetResourceGroup{
-			ResourceGroupName: "test-group",
-			Cause:             "resource group unavailable",
-		},
-	}
+	}, &pderr.ErrClientGetResourceGroup{
+		ResourceGroupName: "test-group",
+		Cause:             "resource group unavailable",
+	})
 
 	if !kerneltype.IsNextGen() {
 		controller, err := rmclient.NewResourceGroupController(
@@ -194,9 +161,7 @@ func TestStarterResourceGroupProviderNonRetryableErrors(t *testing.T) {
 	})
 
 	t.Run("NotFound", func(t *testing.T) {
-		provider := &resourceGroupProviderStub{
-			resourceErr: rmclient.NewResourceGroupNotExistErr("missing-group"),
-		}
+		provider := newResourceGroupProviderStub(t, nil, rmclient.NewResourceGroupNotExistErr("missing-group"))
 		controller := newStarterControllerForTest(t, provider)
 
 		group, err := controller.GetResourceGroup("missing-group")
@@ -208,9 +173,7 @@ func TestStarterResourceGroupProviderNonRetryableErrors(t *testing.T) {
 		ctx, cancel := context.WithCancel(context.Background())
 		cancel()
 
-		provider := &resourceGroupProviderStub{
-			resourceErr: context.Canceled,
-		}
+		provider := newResourceGroupProviderStub(t, nil, context.Canceled)
 		wrapped := newStarterResourceGroupProvider(provider)
 		group, err := wrapped.GetResourceGroup(ctx, "test-group")
 		require.ErrorIs(t, err, context.Canceled)
@@ -218,9 +181,7 @@ func TestStarterResourceGroupProviderNonRetryableErrors(t *testing.T) {
 	})
 
 	t.Run("GenericNonRetryableError", func(t *testing.T) {
-		provider := &resourceGroupProviderStub{
-			resourceErr: errors.New("invalid resource group lookup"),
-		}
+		provider := newResourceGroupProviderStub(t, nil, errors.New("invalid resource group lookup"))
 		controller := newStarterControllerForTest(t, provider)
 
 		group, err := controller.GetResourceGroup("test-group")
@@ -238,9 +199,7 @@ func TestStarterSwitchGroupRejectsMissingGroup(t *testing.T) {
 		require.NoError(t, deploymode.Set(originalDeployMode))
 	})
 
-	provider := &resourceGroupProviderStub{
-		resourceErr: rmclient.NewResourceGroupNotExistErr("missing-switch-group"),
-	}
+	provider := newResourceGroupProviderStub(t, nil, rmclient.NewResourceGroupNotExistErr("missing-switch-group"))
 	controller := newStarterControllerForTest(t, provider)
 	manager := runaway.NewRunawayManager(controller, "127.0.0.1:4000", nil, make(chan struct{}), nil, nil)
 	t.Cleanup(manager.Stop)
diff --git a/pkg/executor/BUILD.bazel b/pkg/executor/BUILD.bazel
index 9b26968e75bc8..562f07bfd6b2c 100644
--- a/pkg/executor/BUILD.bazel
+++ b/pkg/executor/BUILD.bazel
@@ -562,8 +562,6 @@ go_test(
         "@com_github_tikv_client_go_v2//tikv",
         "@com_github_tikv_client_go_v2//tikvrpc",
         "@com_github_tikv_client_go_v2//util",
-        "@com_github_tikv_pd_client//:client",
-        "@com_github_tikv_pd_client//clients/metastorage",
         "@com_github_tikv_pd_client//http",
         "@com_github_tikv_pd_client//opt",
         "@com_github_tikv_pd_client//resource_group/controller",
diff --git a/pkg/executor/adapter_internal_test.go b/pkg/executor/adapter_internal_test.go
index 7aa2237ece5e4..5a5d1263f73ac 100644
--- a/pkg/executor/adapter_internal_test.go
+++ b/pkg/executor/adapter_internal_test.go
@@ -22,8 +22,8 @@ import (
 	"time"
 
 	"github.com/pingcap/kvproto/pkg/meta_storagepb"
-	rmpb "github.com/pingcap/kvproto/pkg/resource_manager"
 	"github.com/pingcap/tidb/pkg/domain"
+	"github.com/pingcap/tidb/pkg/domain/infosync"
 	"github.com/pingcap/tidb/pkg/expression"
 	"github.com/pingcap/tidb/pkg/kv"
 	"github.com/pingcap/tidb/pkg/parser"
@@ -40,8 +40,6 @@ import (
 	"github.com/pingcap/tidb/pkg/util/topsql/stmtstats"
 	"github.com/stretchr/testify/require"
 	"github.com/tikv/client-go/v2/util"
-	pd "github.com/tikv/pd/client"
-	metastorage "github.com/tikv/pd/client/clients/metastorage"
 	"github.com/tikv/pd/client/opt"
 	rmclient "github.com/tikv/pd/client/resource_group/controller"
 )
@@ -452,9 +450,20 @@ func TestObserveStmtFinishedOnTopProfilingIgnores(t *testing.T) {
 }
 
 type mockResourceGroupProvider struct {
+	rmclient.ResourceGroupProvider
 	config *rmclient.Config
 }
 
+func newMockResourceGroupProvider(t *testing.T, config *rmclient.Config) *mockResourceGroupProvider {
+	t.Helper()
+	baseProvider, ok := infosync.NewMockResourceManagerClient(1).(rmclient.ResourceGroupProvider)
+	require.True(t, ok)
+	return &mockResourceGroupProvider{
+		ResourceGroupProvider: baseProvider,
+		config:                config,
+	}
+}
+
 func newMockDomainWithRUVersion(t *testing.T, version rmclient.RUVersion) *domain.Domain {
 	t.Helper()
 	ctx, cancel := context.WithCancel(context.Background())
@@ -462,7 +471,7 @@ func newMockDomainWithRUVersion(t *testing.T, version rmclient.RUVersion) *domai
 
 	cfg := rmclient.DefaultConfig()
 	cfg.RUVersionPolicy = &rmclient.RUVersionPolicy{Default: version}
-	provider := &mockResourceGroupProvider{config: cfg}
+	provider := newMockResourceGroupProvider(t, cfg)
 	controller, err := rmclient.NewResourceGroupController(ctx, 1, provider, nil, 1)
 	require.NoError(t, err)
 
@@ -481,48 +490,4 @@ func (m *mockResourceGroupProvider) Get(ctx context.Context, key []byte, opts ..
 	}, nil
 }
 
-func (*mockResourceGroupProvider) Watch(ctx context.Context, key []byte, opts ...opt.MetaStorageOption) (chan []*meta_storagepb.Event, error) {
-	ch := make(chan []*meta_storagepb.Event)
-	go func() {
-		<-ctx.Done()
-		close(ch)
-	}()
-	return ch, nil
-}
-
-func (*mockResourceGroupProvider) Put(context.Context, []byte, []byte, ...opt.MetaStorageOption) (*meta_storagepb.PutResponse, error) {
-	return &meta_storagepb.PutResponse{}, nil
-}
-
-func (*mockResourceGroupProvider) GetResourceGroup(context.Context, string, ...pd.GetResourceGroupOption) (*rmpb.ResourceGroup, error) {
-	return nil, nil
-}
-
-func (*mockResourceGroupProvider) ListResourceGroups(context.Context, ...pd.GetResourceGroupOption) ([]*rmpb.ResourceGroup, error) {
-	return nil, nil
-}
-
-func (*mockResourceGroupProvider) AddResourceGroup(context.Context, *rmpb.ResourceGroup) (string, error) {
-	return "", nil
-}
-
-func (*mockResourceGroupProvider) ModifyResourceGroup(context.Context, *rmpb.ResourceGroup) (string, error) {
-	return "", nil
-}
-
-func (*mockResourceGroupProvider) DeleteResourceGroup(context.Context, string) (string, error) {
-	return "", nil
-}
-
-func (*mockResourceGroupProvider) AcquireTokenBuckets(context.Context, *rmpb.TokenBucketsRequest) ([]*rmpb.TokenBucketResponse, error) {
-	return nil, nil
-}
-
-func (*mockResourceGroupProvider) LoadResourceGroups(context.Context) ([]*rmpb.ResourceGroup, int64, error) {
-	return nil, 0, nil
-}
-
-var (
-	_ metastorage.Client             = (*mockResourceGroupProvider)(nil)
-	_ rmclient.ResourceGroupProvider = (*mockResourceGroupProvider)(nil)
-)
+var _ rmclient.ResourceGroupProvider = (*mockResourceGroupProvider)(nil)

From a633842009a7061fc41ac579e0eed81264ba2bff Mon Sep 17 00:00:00 2001
From: ystaticy <y_static_y@sina.com>
Date: Tue, 14 Jul 2026 15:16:00 +0800
Subject: [PATCH 11/21]  fix ut

Signed-off-by: ystaticy <y_static_y@sina.com>
---
 pkg/domain/runaway_test.go | 20 +++++++++++++-------
 1 file changed, 13 insertions(+), 7 deletions(-)

diff --git a/pkg/domain/runaway_test.go b/pkg/domain/runaway_test.go
index 3184f44c2ffd3..198f448e36f5b 100644
--- a/pkg/domain/runaway_test.go
+++ b/pkg/domain/runaway_test.go
@@ -226,19 +226,25 @@ func TestStarterSwitchGroupRejectsMissingGroup(t *testing.T) {
 func TestResourceGroupsControllerOptionsUseStarterPodNamespaceForVIPWaitRetry(t *testing.T) {
 	restoreConfig := config.RestoreFunc()
 	t.Cleanup(restoreConfig)
-	originalDeployMode := deploymode.Get()
-	t.Cleanup(func() {
-		require.NoError(t, deploymode.Set(originalDeployMode))
-	})
-	require.NoError(t, deploymode.Set(deploymode.Starter))
+	vipOptionCount := 3
+	standardOptionCount := 1
+	if kerneltype.IsNextGen() {
+		originalDeployMode := deploymode.Get()
+		t.Cleanup(func() {
+			require.NoError(t, deploymode.Set(originalDeployMode))
+		})
+		require.NoError(t, deploymode.Set(deploymode.Starter))
+		vipOptionCount = 4
+		standardOptionCount = 2
+	}
 
 	config.UpdateGlobal(func(conf *config.Config) {
 		conf.StarterParams.PodNamespace = "starter-vip-ns"
 	})
-	require.Len(t, newResourceGroupsControllerOptions(), 4)
+	require.Len(t, newResourceGroupsControllerOptions(), vipOptionCount)
 
 	config.UpdateGlobal(func(conf *config.Config) {
 		conf.StarterParams.PodNamespace = "starter-standard-ns"
 	})
-	require.Len(t, newResourceGroupsControllerOptions(), 2)
+	require.Len(t, newResourceGroupsControllerOptions(), standardOptionCount)
 }

From cf2bf7f8aa71284bc9b47ecb12bb53d941d7743f Mon Sep 17 00:00:00 2001
From: ystaticy <y_static_y@sina.com>
Date: Tue, 14 Jul 2026 17:12:47 +0800
Subject: [PATCH 12/21]  fix code format

Signed-off-by: ystaticy <y_static_y@sina.com>
---
 pkg/domain/BUILD.bazel                        |  1 +
 .../resource_group_controller_options.go      | 49 +++++++++++++++++++
 pkg/domain/resource_group_provider.go         | 16 ++++++
 pkg/domain/runaway.go                         | 41 ----------------
 4 files changed, 66 insertions(+), 41 deletions(-)
 create mode 100644 pkg/domain/resource_group_controller_options.go

diff --git a/pkg/domain/BUILD.bazel b/pkg/domain/BUILD.bazel
index dc84cdd7d002e..42c0d4fde0065 100644
--- a/pkg/domain/BUILD.bazel
+++ b/pkg/domain/BUILD.bazel
@@ -11,6 +11,7 @@ go_library(
         "optimize_trace.go",
         "plan_replayer.go",
         "plan_replayer_dump.go",
+        "resource_group_controller_options.go",
         "resource_group_provider.go",
         "ru_stats.go",
         "runaway.go",
diff --git a/pkg/domain/resource_group_controller_options.go b/pkg/domain/resource_group_controller_options.go
new file mode 100644
index 0000000000000..dcb7a277346bf
--- /dev/null
+++ b/pkg/domain/resource_group_controller_options.go
@@ -0,0 +1,49 @@
+// Copyright 2026 PingCAP, Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package domain
+
+import (
+	"strings"
+	"time"
+
+	"github.com/pingcap/tidb/pkg/config"
+	"github.com/pingcap/tidb/pkg/config/deploymode"
+	"github.com/pingcap/tidb/pkg/resourcegroup/runaway"
+	rmclient "github.com/tikv/pd/client/resource_group/controller"
+)
+
+const (
+	defaultDegradedModeWaitTimeout = 3 * time.Second / 2
+	tokenWaitRetryInterval         = 100 * time.Millisecond
+	tokenWaitRetryTimes            = 20
+)
+
+func newResourceGroupsControllerOptions() []rmclient.ResourceControlCreateOption {
+	opts := []rmclient.ResourceControlCreateOption{
+		rmclient.WithMaxWaitDuration(runaway.MaxWaitDuration),
+	}
+	if deploymode.IsStarter() {
+		opts = append(opts,
+			rmclient.WithDegradedModeWaitDuration(defaultDegradedModeWaitTimeout),
+		)
+	}
+	if strings.Contains(config.GetGlobalConfig().StarterParams.PodNamespace, "vip") {
+		opts = append(opts,
+			rmclient.WithWaitRetryInterval(tokenWaitRetryInterval),
+			rmclient.WithWaitRetryTimes(tokenWaitRetryTimes),
+		)
+	}
+	return opts
+}
diff --git a/pkg/domain/resource_group_provider.go b/pkg/domain/resource_group_provider.go
index 91d5c1570acd8..0f6b5c44e4823 100644
--- a/pkg/domain/resource_group_provider.go
+++ b/pkg/domain/resource_group_provider.go
@@ -25,6 +25,22 @@ import (
 	rmclient "github.com/tikv/pd/client/resource_group/controller"
 )
 
+const (
+	defaultDegradedRUFillRate   = 2_000_000
+	defaultDegradedRUBurstLimit = 50_000_000_000
+)
+
+func newDefaultDegradedRUSettings() *rmpb.GroupRequestUnitSettings {
+	return &rmpb.GroupRequestUnitSettings{
+		RU: &rmpb.TokenBucket{
+			Settings: &rmpb.TokenLimitSettings{
+				FillRate:   defaultDegradedRUFillRate,
+				BurstLimit: defaultDegradedRUBurstLimit,
+			},
+		},
+	}
+}
+
 // starterResourceGroupProvider wraps a resource group provider and synthesizes
 // degraded resource groups only when resource-manager lookup fails due to
 // unavailability.
diff --git a/pkg/domain/runaway.go b/pkg/domain/runaway.go
index 4f6cc7710a39a..8be3f00e11590 100644
--- a/pkg/domain/runaway.go
+++ b/pkg/domain/runaway.go
@@ -18,11 +18,7 @@ import (
 	"context"
 	"net"
 	"strconv"
-	"strings"
-	"time"
 
-	rmpb "github.com/pingcap/kvproto/pkg/resource_manager"
-	"github.com/pingcap/tidb/pkg/config"
 	"github.com/pingcap/tidb/pkg/config/deploymode"
 	"github.com/pingcap/tidb/pkg/domain/infosync"
 	"github.com/pingcap/tidb/pkg/resourcegroup/runaway"
@@ -33,43 +29,6 @@ import (
 	rmclient "github.com/tikv/pd/client/resource_group/controller"
 )
 
-const (
-	defaultDegradedRUFillRate      = 2_000_000
-	defaultDegradedRUBurstLimit    = 50_000_000_000
-	defaultDegradedModeWaitTimeout = 3 * time.Second / 2
-	tokenWaitRetryInterval         = 100 * time.Millisecond
-	tokenWaitRetryTimes            = 20
-)
-
-func newDefaultDegradedRUSettings() *rmpb.GroupRequestUnitSettings {
-	return &rmpb.GroupRequestUnitSettings{
-		RU: &rmpb.TokenBucket{
-			Settings: &rmpb.TokenLimitSettings{
-				FillRate:   defaultDegradedRUFillRate,
-				BurstLimit: defaultDegradedRUBurstLimit,
-			},
-		},
-	}
-}
-
-func newResourceGroupsControllerOptions() []rmclient.ResourceControlCreateOption {
-	opts := []rmclient.ResourceControlCreateOption{
-		rmclient.WithMaxWaitDuration(runaway.MaxWaitDuration),
-	}
-	if deploymode.IsStarter() {
-		opts = append(opts,
-			rmclient.WithDegradedModeWaitDuration(defaultDegradedModeWaitTimeout),
-		)
-	}
-	if strings.Contains(config.GetGlobalConfig().StarterParams.PodNamespace, "vip") {
-		opts = append(opts,
-			rmclient.WithWaitRetryInterval(tokenWaitRetryInterval),
-			rmclient.WithWaitRetryTimes(tokenWaitRetryTimes),
-		)
-	}
-	return opts
-}
-
 func (do *Domain) initResourceGroupsController(ctx context.Context, pdClient pd.Client, uniqueID uint64) error {
 	if pdClient == nil {
 		logutil.BgLogger().Warn("cannot setup up resource controller, not using tikv storage")

From 7a97d4e38f6e1b77c582c78bc76a1ac8126a68d0 Mon Sep 17 00:00:00 2001
From: ystaticy <y_static_y@sina.com>
Date: Tue, 14 Jul 2026 19:49:54 +0800
Subject: [PATCH 13/21]  use with degradedResourceGroup

Signed-off-by: ystaticy <y_static_y@sina.com>
---
 pkg/domain/BUILD.bazel                        |   6 +-
 .../resource_group_controller_options.go      |  17 +++
 pkg/domain/resource_group_provider.go         | 132 ------------------
 pkg/domain/resource_group_provider_test.go    |  89 ------------
 pkg/domain/runaway.go                         |   7 +-
 pkg/domain/runaway_test.go                    |  73 +++++++---
 6 files changed, 74 insertions(+), 250 deletions(-)
 delete mode 100644 pkg/domain/resource_group_provider.go
 delete mode 100644 pkg/domain/resource_group_provider_test.go

diff --git a/pkg/domain/BUILD.bazel b/pkg/domain/BUILD.bazel
index 42c0d4fde0065..e3d3d26942457 100644
--- a/pkg/domain/BUILD.bazel
+++ b/pkg/domain/BUILD.bazel
@@ -12,7 +12,6 @@ go_library(
         "plan_replayer.go",
         "plan_replayer_dump.go",
         "resource_group_controller_options.go",
-        "resource_group_provider.go",
         "ru_stats.go",
         "runaway.go",
         "schema_checker.go",
@@ -126,7 +125,6 @@ go_library(
         "@com_github_tikv_client_go_v2//txnkv/transaction",
         "@com_github_tikv_pd_client//:client",
         "@com_github_tikv_pd_client//constants",
-        "@com_github_tikv_pd_client//errs",
         "@com_github_tikv_pd_client//http",
         "@com_github_tikv_pd_client//opt",
         "@com_github_tikv_pd_client//pkg/caller",
@@ -152,7 +150,6 @@ go_test(
         "plan_replayer_handle_test.go",
         "plan_replayer_slow_log_test.go",
         "plan_replayer_test.go",
-        "resource_group_provider_test.go",
         "ru_stats_test.go",
         "runaway_test.go",
         "schema_checker_test.go",
@@ -160,7 +157,7 @@ go_test(
     ],
     embed = [":domain"],
     flaky = True,
-    shard_count = 35,
+    shard_count = 34,
     deps = [
         "//pkg/config",
         "//pkg/config/deploymode",
@@ -200,6 +197,7 @@ go_test(
         "@com_github_ngaut_pools//:pools",
         "@com_github_pingcap_errors//:errors",
         "@com_github_pingcap_failpoint//:failpoint",
+        "@com_github_pingcap_kvproto//pkg/kvrpcpb",
         "@com_github_pingcap_kvproto//pkg/metapb",
         "@com_github_pingcap_kvproto//pkg/resource_manager",
         "@com_github_prometheus_client_model//go",
diff --git a/pkg/domain/resource_group_controller_options.go b/pkg/domain/resource_group_controller_options.go
index dcb7a277346bf..5df7a378f75a8 100644
--- a/pkg/domain/resource_group_controller_options.go
+++ b/pkg/domain/resource_group_controller_options.go
@@ -18,6 +18,7 @@ import (
 	"strings"
 	"time"
 
+	rmpb "github.com/pingcap/kvproto/pkg/resource_manager"
 	"github.com/pingcap/tidb/pkg/config"
 	"github.com/pingcap/tidb/pkg/config/deploymode"
 	"github.com/pingcap/tidb/pkg/resourcegroup/runaway"
@@ -25,17 +26,33 @@ import (
 )
 
 const (
+	defaultDegradedRUFillRate      = 2_000_000
+	defaultDegradedRUBurstLimit    = 50_000_000_000
 	defaultDegradedModeWaitTimeout = 3 * time.Second / 2
 	tokenWaitRetryInterval         = 100 * time.Millisecond
 	tokenWaitRetryTimes            = 20
 )
 
+func newDefaultDegradedRUSettings() *rmpb.GroupRequestUnitSettings {
+	return &rmpb.GroupRequestUnitSettings{
+		RU: &rmpb.TokenBucket{
+			Settings: &rmpb.TokenLimitSettings{
+				FillRate:   defaultDegradedRUFillRate,
+				BurstLimit: defaultDegradedRUBurstLimit,
+			},
+		},
+	}
+}
+
 func newResourceGroupsControllerOptions() []rmclient.ResourceControlCreateOption {
 	opts := []rmclient.ResourceControlCreateOption{
 		rmclient.WithMaxWaitDuration(runaway.MaxWaitDuration),
 	}
 	if deploymode.IsStarter() {
 		opts = append(opts,
+			// Keep degraded-group synthesis inside the controller so degraded
+			// resource groups are not inserted into the controller cache.
+			rmclient.WithDegradedRUSettings(newDefaultDegradedRUSettings()),
 			rmclient.WithDegradedModeWaitDuration(defaultDegradedModeWaitTimeout),
 		)
 	}
diff --git a/pkg/domain/resource_group_provider.go b/pkg/domain/resource_group_provider.go
deleted file mode 100644
index 0f6b5c44e4823..0000000000000
--- a/pkg/domain/resource_group_provider.go
+++ /dev/null
@@ -1,132 +0,0 @@
-// Copyright 2026 PingCAP, Inc.
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-//     http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-package domain
-
-import (
-	"context"
-	stderrors "errors"
-	"strings"
-
-	rmpb "github.com/pingcap/kvproto/pkg/resource_manager"
-	pd "github.com/tikv/pd/client"
-	pderr "github.com/tikv/pd/client/errs"
-	rmclient "github.com/tikv/pd/client/resource_group/controller"
-)
-
-const (
-	defaultDegradedRUFillRate   = 2_000_000
-	defaultDegradedRUBurstLimit = 50_000_000_000
-)
-
-func newDefaultDegradedRUSettings() *rmpb.GroupRequestUnitSettings {
-	return &rmpb.GroupRequestUnitSettings{
-		RU: &rmpb.TokenBucket{
-			Settings: &rmpb.TokenLimitSettings{
-				FillRate:   defaultDegradedRUFillRate,
-				BurstLimit: defaultDegradedRUBurstLimit,
-			},
-		},
-	}
-}
-
-// starterResourceGroupProvider wraps a resource group provider and synthesizes
-// degraded resource groups only when resource-manager lookup fails due to
-// unavailability.
-type starterResourceGroupProvider struct {
-	rmclient.ResourceGroupProvider
-	degradedRUSettings *rmpb.GroupRequestUnitSettings
-}
-
-func newStarterResourceGroupProvider(provider rmclient.ResourceGroupProvider) *starterResourceGroupProvider {
-	return &starterResourceGroupProvider{
-		ResourceGroupProvider: provider,
-		degradedRUSettings:    newDefaultDegradedRUSettings(),
-	}
-}
-
-func (p *starterResourceGroupProvider) GetResourceGroup(
-	ctx context.Context, resourceGroupName string, opts ...pd.GetResourceGroupOption,
-) (*rmpb.ResourceGroup, error) {
-	if err := ctx.Err(); err != nil {
-		return nil, err
-	}
-	group, err := p.ResourceGroupProvider.GetResourceGroup(ctx, resourceGroupName, opts...)
-	if err == nil {
-		return group, nil
-	}
-	if !shouldUseDegradedResourceGroupFallback(ctx, err) {
-		return nil, err
-	}
-	return newDegradedResourceGroup(resourceGroupName, p.degradedRUSettings), nil
-}
-
-func newDegradedResourceGroup(name string, ruSettings *rmpb.GroupRequestUnitSettings) *rmpb.ResourceGroup {
-	return &rmpb.ResourceGroup{
-		Name:       name,
-		Mode:       rmpb.GroupMode_RUMode,
-		RUSettings: ruSettings,
-	}
-}
-
-func shouldUseDegradedResourceGroupFallback(ctx context.Context, err error) bool {
-	if err == nil {
-		return false
-	}
-	if ctx.Err() != nil {
-		return false
-	}
-	if stderrors.Is(err, context.Canceled) || stderrors.Is(err, context.DeadlineExceeded) {
-		return false
-	}
-	if isResourceGroupNotExistError(err) {
-		return false
-	}
-	if stderrors.Is(err, pderr.ErrClientResourceGroupConfigUnavailable) {
-		return true
-	}
-	var getRGErr *pderr.ErrClientGetResourceGroup
-	if stderrors.As(err, &getRGErr) {
-		return isResourceManagerUnavailableCause(getRGErr.Cause)
-	}
-	return isResourceManagerUnavailableCause(err.Error())
-}
-
-func isResourceGroupNotExistError(err error) bool {
-	var getRGErr *pderr.ErrClientGetResourceGroup
-	if !stderrors.As(err, &getRGErr) {
-		return false
-	}
-	return isResourceGroupNotExistCause(getRGErr.Cause)
-}
-
-func isResourceGroupNotExistCause(cause string) bool {
-	lower := strings.ToLower(cause)
-	return strings.Contains(lower, "does not exist") ||
-		strings.Contains(lower, "not found") ||
-		strings.Contains(lower, "not exist")
-}
-
-func isResourceManagerUnavailableCause(cause string) bool {
-	if isResourceGroupNotExistCause(cause) {
-		return false
-	}
-	lower := strings.ToLower(cause)
-	return strings.Contains(lower, "unavailable") ||
-		strings.Contains(lower, "connection refused") ||
-		strings.Contains(lower, "connection reset") ||
-		strings.Contains(lower, "deadline exceeded") ||
-		strings.Contains(lower, "transport is closing") ||
-		strings.Contains(lower, "rpc error")
-}
diff --git a/pkg/domain/resource_group_provider_test.go b/pkg/domain/resource_group_provider_test.go
deleted file mode 100644
index d51dcdd73bc96..0000000000000
--- a/pkg/domain/resource_group_provider_test.go
+++ /dev/null
@@ -1,89 +0,0 @@
-// Copyright 2026 PingCAP, Inc.
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-//     http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-package domain
-
-import (
-	"context"
-	"errors"
-	"testing"
-
-	"github.com/stretchr/testify/require"
-	pderr "github.com/tikv/pd/client/errs"
-)
-
-func TestShouldUseDegradedResourceGroupFallback(t *testing.T) {
-	ctx := context.Background()
-	canceledCtx, cancel := context.WithCancel(context.Background())
-	cancel()
-
-	tests := []struct {
-		name string
-		ctx  context.Context
-		err  error
-		want bool
-	}{
-		{
-			name: "resource manager unavailable",
-			ctx:  ctx,
-			err: &pderr.ErrClientGetResourceGroup{
-				ResourceGroupName: "rg1",
-				Cause:             "resource group unavailable",
-			},
-			want: true,
-		},
-		{
-			name: "resource group not found",
-			ctx:  ctx,
-			err: &pderr.ErrClientGetResourceGroup{
-				ResourceGroupName: "rg1",
-				Cause:             "resource group does not exist",
-			},
-			want: false,
-		},
-		{
-			name: "context canceled",
-			ctx:  canceledCtx,
-			err: &pderr.ErrClientGetResourceGroup{
-				ResourceGroupName: "rg1",
-				Cause:             "resource group unavailable",
-			},
-			want: false,
-		},
-		{
-			name: "lookup canceled",
-			ctx:  ctx,
-			err:  context.Canceled,
-			want: false,
-		},
-		{
-			name: "config unavailable",
-			ctx:  ctx,
-			err:  pderr.ErrClientResourceGroupConfigUnavailable.FastGenByArgs("not configured"),
-			want: true,
-		},
-		{
-			name: "generic non retryable",
-			ctx:  ctx,
-			err:  errors.New("invalid resource group lookup"),
-			want: false,
-		},
-	}
-
-	for _, tt := range tests {
-		t.Run(tt.name, func(t *testing.T) {
-			require.Equal(t, tt.want, shouldUseDegradedResourceGroupFallback(tt.ctx, tt.err))
-		})
-	}
-}
diff --git a/pkg/domain/runaway.go b/pkg/domain/runaway.go
index 8be3f00e11590..439369bc2536f 100644
--- a/pkg/domain/runaway.go
+++ b/pkg/domain/runaway.go
@@ -19,7 +19,6 @@ import (
 	"net"
 	"strconv"
 
-	"github.com/pingcap/tidb/pkg/config/deploymode"
 	"github.com/pingcap/tidb/pkg/domain/infosync"
 	"github.com/pingcap/tidb/pkg/resourcegroup/runaway"
 	"github.com/pingcap/tidb/pkg/util/logutil"
@@ -40,11 +39,7 @@ func (do *Domain) initResourceGroupsController(ctx context.Context, pdClient pd.
 	if codec := do.Store().GetCodec(); codec != nil {
 		keyspaceID = uint32(codec.GetKeyspaceID())
 	}
-	var provider rmclient.ResourceGroupProvider = pdClient
-	if deploymode.IsStarter() {
-		provider = newStarterResourceGroupProvider(pdClient)
-	}
-	control, err := rmclient.NewResourceGroupController(ctx, uniqueID, provider, nil, keyspaceID, newResourceGroupsControllerOptions()...)
+	control, err := rmclient.NewResourceGroupController(ctx, uniqueID, pdClient, nil, keyspaceID, newResourceGroupsControllerOptions()...)
 	if err != nil {
 		return err
 	}
diff --git a/pkg/domain/runaway_test.go b/pkg/domain/runaway_test.go
index 198f448e36f5b..ce0b57d74d265 100644
--- a/pkg/domain/runaway_test.go
+++ b/pkg/domain/runaway_test.go
@@ -20,6 +20,7 @@ import (
 	"testing"
 	"time"
 
+	"github.com/pingcap/kvproto/pkg/kvrpcpb"
 	rmpb "github.com/pingcap/kvproto/pkg/resource_manager"
 	"github.com/pingcap/tidb/pkg/config"
 	"github.com/pingcap/tidb/pkg/config/deploymode"
@@ -66,7 +67,7 @@ func newStarterControllerForTest(t *testing.T, provider rmclient.ResourceGroupPr
 	controller, err := rmclient.NewResourceGroupController(
 		ctx,
 		1,
-		newStarterResourceGroupProvider(provider),
+		provider,
 		nil,
 		0,
 		newResourceGroupsControllerOptions()...,
@@ -129,9 +130,33 @@ func TestResourceGroupsControllerOptionsProvideDegradedFallback(t *testing.T) {
 	controllerWithFallback := newStarterControllerForTest(t, provider)
 	group, err := controllerWithFallback.GetResourceGroup("test-group")
 	require.NoError(t, err)
-	require.Equal(t, newDegradedResourceGroup("test-group", newDefaultDegradedRUSettings()), group)
+	require.Equal(t, &rmpb.ResourceGroup{
+		Name:       "test-group",
+		Mode:       rmpb.GroupMode_RUMode,
+		RUSettings: newDefaultDegradedRUSettings(),
+	}, group)
+
+	// The degraded group should not be cached. Once the provider recovers, the
+	// next lookup should observe the real resource-group metadata.
+	provider.resourceGroup = &rmpb.ResourceGroup{
+		Name: "test-group",
+		Mode: rmpb.GroupMode_RUMode,
+		RUSettings: &rmpb.GroupRequestUnitSettings{
+			RU: &rmpb.TokenBucket{
+				Settings: &rmpb.TokenLimitSettings{FillRate: 1},
+			},
+		},
+	}
+	provider.resourceErr = nil
+	group, err = controllerWithFallback.GetResourceGroup("test-group")
+	require.NoError(t, err)
+	require.Equal(t, provider.resourceGroup, group)
 
 	require.NoError(t, deploymode.Set(deploymode.Premium))
+	provider = newResourceGroupProviderStub(t, nil, &pderr.ErrClientGetResourceGroup{
+		ResourceGroupName: "test-group",
+		Cause:             "resource group unavailable",
+	})
 	controllerWithoutFallback, err := rmclient.NewResourceGroupController(
 		ctx,
 		2,
@@ -151,7 +176,7 @@ func TestResourceGroupsControllerOptionsProvideDegradedFallback(t *testing.T) {
 	require.Nil(t, group)
 }
 
-func TestStarterResourceGroupProviderNonRetryableErrors(t *testing.T) {
+func TestStarterControllerGetResourceGroupUsesDegradedSettingsOnErrors(t *testing.T) {
 	if !kerneltype.IsNextGen() {
 		t.Skip("Starter deploy mode is only available in NextGen builds")
 	}
@@ -160,24 +185,30 @@ func TestStarterResourceGroupProviderNonRetryableErrors(t *testing.T) {
 		require.NoError(t, deploymode.Set(originalDeployMode))
 	})
 
+	expectedGroup := func(name string) *rmpb.ResourceGroup {
+		return &rmpb.ResourceGroup{
+			Name:       name,
+			Mode:       rmpb.GroupMode_RUMode,
+			RUSettings: newDefaultDegradedRUSettings(),
+		}
+	}
+
 	t.Run("NotFound", func(t *testing.T) {
 		provider := newResourceGroupProviderStub(t, nil, rmclient.NewResourceGroupNotExistErr("missing-group"))
 		controller := newStarterControllerForTest(t, provider)
 
 		group, err := controller.GetResourceGroup("missing-group")
-		require.Error(t, err)
-		require.Nil(t, group)
+		require.NoError(t, err)
+		require.Equal(t, expectedGroup("missing-group"), group)
 	})
 
 	t.Run("ContextCanceled", func(t *testing.T) {
-		ctx, cancel := context.WithCancel(context.Background())
-		cancel()
-
 		provider := newResourceGroupProviderStub(t, nil, context.Canceled)
-		wrapped := newStarterResourceGroupProvider(provider)
-		group, err := wrapped.GetResourceGroup(ctx, "test-group")
-		require.ErrorIs(t, err, context.Canceled)
-		require.Nil(t, group)
+		controller := newStarterControllerForTest(t, provider)
+
+		group, err := controller.GetResourceGroup("test-group")
+		require.NoError(t, err)
+		require.Equal(t, expectedGroup("test-group"), group)
 	})
 
 	t.Run("GenericNonRetryableError", func(t *testing.T) {
@@ -185,12 +216,12 @@ func TestStarterResourceGroupProviderNonRetryableErrors(t *testing.T) {
 		controller := newStarterControllerForTest(t, provider)
 
 		group, err := controller.GetResourceGroup("test-group")
-		require.Error(t, err)
-		require.Nil(t, group)
+		require.NoError(t, err)
+		require.Equal(t, expectedGroup("test-group"), group)
 	})
 }
 
-func TestStarterSwitchGroupRejectsMissingGroup(t *testing.T) {
+func TestStarterSwitchGroupUsesDegradedGroupOnLookupError(t *testing.T) {
 	if !kerneltype.IsNextGen() {
 		t.Skip("Starter deploy mode is only available in NextGen builds")
 	}
@@ -218,9 +249,13 @@ func TestStarterSwitchGroupRejectsMissingGroup(t *testing.T) {
 	)
 
 	require.NoError(t, checker.CheckThresholds(nil, 10, nil))
-	req := &tikvrpc.Request{}
+	req := &tikvrpc.Request{
+		Context: kvrpcpb.Context{
+			ResourceControlContext: &kvrpcpb.ResourceControlContext{},
+		},
+	}
 	require.NoError(t, checker.BeforeCopRequest(req))
-	require.Empty(t, req.GetResourceControlContext().GetResourceGroupName())
+	require.Equal(t, "missing-switch-group", req.GetResourceControlContext().GetResourceGroupName())
 }
 
 func TestResourceGroupsControllerOptionsUseStarterPodNamespaceForVIPWaitRetry(t *testing.T) {
@@ -234,8 +269,8 @@ func TestResourceGroupsControllerOptionsUseStarterPodNamespaceForVIPWaitRetry(t
 			require.NoError(t, deploymode.Set(originalDeployMode))
 		})
 		require.NoError(t, deploymode.Set(deploymode.Starter))
-		vipOptionCount = 4
-		standardOptionCount = 2
+		vipOptionCount = 5
+		standardOptionCount = 3
 	}
 
 	config.UpdateGlobal(func(conf *config.Config) {

From d1989e5733d061380afd38fb87150482d98492c6 Mon Sep 17 00:00:00 2001
From: ystaticy <y_static_y@sina.com>
Date: Tue, 14 Jul 2026 22:12:47 +0800
Subject: [PATCH 14/21]  fix config

Signed-off-by: ystaticy <y_static_y@sina.com>
---
 cmd/tidb-server/main.go      | 29 +++++++++++++++++------------
 cmd/tidb-server/main_test.go | 22 ++++++++++++++++------
 pkg/config/config.go         |  9 +++++++++
 3 files changed, 42 insertions(+), 18 deletions(-)

diff --git a/cmd/tidb-server/main.go b/cmd/tidb-server/main.go
index 516971d745e07..5102accf8c6f3 100644
--- a/cmd/tidb-server/main.go
+++ b/cmd/tidb-server/main.go
@@ -711,9 +711,7 @@ func overrideConfig(cfg *config.Config, fset *flag.FlagSet) {
 		actualFlags[f.Name] = true
 	})
 	if actualFlags[nmStarterParams] && cfg.DeployMode == deploymode.Starter {
-		params, err := parseStarterAdditionalParams(getStarterAdditionalParams())
-		terror.MustNil(err)
-		cfg.StarterParams.PodNamespace = params.podNamespace
+		terror.MustNil(applyStarterAdditionalParams(cfg, getStarterAdditionalParams()))
 	}
 
 	// Base
@@ -1406,6 +1404,18 @@ func parseStarterAdditionalParams(raw string) (starterParams, error) {
 	return params, nil
 }
 
+func applyStarterAdditionalParams(cfg *config.Config, raw string) error {
+	params, err := parseStarterAdditionalParams(raw)
+	if err != nil {
+		return err
+	}
+	cfg.StarterParams.ManagerNamespace = params.managerNamespace
+	cfg.StarterParams.PodName = params.podName
+	cfg.StarterParams.PodIP = params.podIP
+	cfg.StarterParams.PodNamespace = params.podNamespace
+	return nil
+}
+
 func getStarterAdditionalParams() string {
 	if starterAdditionalParams == nil {
 		return ""
@@ -1429,23 +1439,18 @@ func createMgrClientForStarter() (tidbmanager.Client, error) {
 		return nil, err
 	}
 
-	params, err := parseStarterAdditionalParams(getStarterAdditionalParams())
-	if err != nil {
-		return nil, err
-	}
-
 	managerAddr := cfg.StarterParams.ManagerAddr
 	if managerAddr == "" {
-		managerNs := params.managerNamespace
+		managerNs := cfg.StarterParams.ManagerNamespace
 		if managerNs == "" {
 			return nil, fmt.Errorf("manager notifier requires manager-addr config or manager-namespace in --starter-additional-params")
 		}
 		managerAddr = fmt.Sprintf("manager-server.%s.svc:8000", managerNs)
 	}
 
-	podName := params.podName
-	podIP := params.podIP
-	namespace := params.podNamespace
+	podName := cfg.StarterParams.PodName
+	podIP := cfg.StarterParams.PodIP
+	namespace := cfg.StarterParams.PodNamespace
 	if podName == "" || podIP == "" || namespace == "" {
 		return nil, fmt.Errorf("manager notifier requires --starter-additional-params with pod-name, pod-ip and pod-namespace: pod-name=%q, pod-ip=%q, pod-namespace=%q",
 			podName, podIP, namespace)
diff --git a/cmd/tidb-server/main_test.go b/cmd/tidb-server/main_test.go
index 9650261a94e54..50f5e0d5bf8de 100644
--- a/cmd/tidb-server/main_test.go
+++ b/cmd/tidb-server/main_test.go
@@ -92,6 +92,8 @@ func TestOverrideConfigKeyspaceActivateMode(t *testing.T) {
 	cfg.DeployMode = deploymode.Starter
 	overrideConfig(cfg, fset)
 	require.True(t, cfg.KeyspaceActivateMode)
+	require.Equal(t, "pod-1", cfg.StarterParams.PodName)
+	require.Equal(t, "10.0.0.1", cfg.StarterParams.PodIP)
 	require.Equal(t, "ns-1", cfg.StarterParams.PodNamespace)
 	require.Equal(t, "pod-name=pod-1,pod-ip=10.0.0.1,pod-namespace=ns-1", *starterAdditionalParams)
 }
@@ -210,25 +212,33 @@ func TestCreateMgrClientRequiresPodIdentityInStarter(t *testing.T) {
 	require.ErrorContains(t, err, "manager notifier requires --starter-additional-params")
 
 	duplicatedParam := "pod-name=pod-1,pod-name=pod-2,pod-ip=10.0.0.1,pod-namespace=ns-1"
-	starterAdditionalParams = &duplicatedParam
-	_, err = createMgrClientForStarter()
+	config.UpdateGlobal(func(conf *config.Config) {
+		conf.StarterParams.ManagerNamespace = ""
+		conf.StarterParams.PodName = ""
+		conf.StarterParams.PodIP = ""
+		conf.StarterParams.PodNamespace = ""
+	})
+	err = applyStarterAdditionalParams(config.GetGlobalConfig(), duplicatedParam)
 	require.ErrorContains(t, err, `starter additional param "pod-name" is duplicated`)
 
 	unknownParam := "pod-name=pod-1,pod-ip=10.0.0.1,pod-namespace=ns-1,unknown=value"
-	starterAdditionalParams = &unknownParam
-	_, err = createMgrClientForStarter()
+	err = applyStarterAdditionalParams(config.GetGlobalConfig(), unknownParam)
 	require.ErrorContains(t, err, `unknown starter additional param "unknown"`)
 
 	config.UpdateGlobal(func(conf *config.Config) {
 		conf.StarterParams.ManagerAddr = ""
+		conf.StarterParams.ManagerNamespace = ""
+		conf.StarterParams.PodName = ""
+		conf.StarterParams.PodIP = ""
+		conf.StarterParams.PodNamespace = ""
 	})
 	missingManagerNamespace := "pod-name=pod-1,pod-ip=10.0.0.1,pod-namespace=ns-1"
-	starterAdditionalParams = &missingManagerNamespace
+	require.NoError(t, applyStarterAdditionalParams(config.GetGlobalConfig(), missingManagerNamespace))
 	_, err = createMgrClientForStarter()
 	require.ErrorContains(t, err, "manager notifier requires manager-addr config or manager-namespace in --starter-additional-params")
 
 	validParams := "manager-namespace=manager-ns,pod-name=pod-1,pod-ip=10.0.0.1,pod-namespace=ns-1"
-	starterAdditionalParams = &validParams
+	require.NoError(t, applyStarterAdditionalParams(config.GetGlobalConfig(), validParams))
 	cli, err := createMgrClientForStarter()
 	require.NoError(t, err)
 	require.NotNil(t, cli)
diff --git a/pkg/config/config.go b/pkg/config/config.go
index 32a61be17b6f0..8d3236bbf3895 100644
--- a/pkg/config/config.go
+++ b/pkg/config/config.go
@@ -1094,6 +1094,15 @@ type StarterParams struct {
 	// ManagerAddr is the TiDB manager address used by the shutdown notifier.
 	// When empty and EnableManagerNotifier is true, the Starter path derives the service address from starter additional params.
 	ManagerAddr string `toml:"manager-addr" json:"manager-addr,omitempty"`
+	// ManagerNamespace captures the runtime manager namespace from --starter-additional-params.
+	// It is command-line derived runtime metadata rather than file-backed config.
+	ManagerNamespace string `toml:"-" json:"-"`
+	// PodName captures the runtime pod name from --starter-additional-params.
+	// It is command-line derived runtime metadata rather than file-backed config.
+	PodName string `toml:"-" json:"-"`
+	// PodIP captures the runtime pod IP from --starter-additional-params.
+	// It is command-line derived runtime metadata rather than file-backed config.
+	PodIP string `toml:"-" json:"-"`
 	// PodNamespace captures the runtime pod namespace from --starter-additional-params.
 	// It is command-line derived runtime metadata rather than file-backed config.
 	PodNamespace string `toml:"-" json:"-"`

From 0ea629f60ac274adc532c0d0424ce2e18c11ec63 Mon Sep 17 00:00:00 2001
From: ystaticy <y_static_y@sina.com>
Date: Wed, 15 Jul 2026 22:34:40 +0800
Subject: [PATCH 15/21]  fix comments

Signed-off-by: ystaticy <y_static_y@sina.com>
---
 pkg/domain/runaway_test.go | 32 ++++++++++++++++----------------
 1 file changed, 16 insertions(+), 16 deletions(-)

diff --git a/pkg/domain/runaway_test.go b/pkg/domain/runaway_test.go
index ce0b57d74d265..dec2fe7a54e04 100644
--- a/pkg/domain/runaway_test.go
+++ b/pkg/domain/runaway_test.go
@@ -80,6 +80,18 @@ func newStarterControllerForTest(t *testing.T, provider rmclient.ResourceGroupPr
 	return controller
 }
 
+func requireDegradedResourceGroup(t *testing.T, group *rmpb.ResourceGroup, name string) {
+	t.Helper()
+	require.NotNil(t, group)
+	require.Equal(t, name, group.Name)
+	require.Equal(t, rmpb.GroupMode_RUMode, group.Mode)
+	require.NotNil(t, group.RUSettings)
+	require.NotNil(t, group.RUSettings.RU)
+	require.NotNil(t, group.RUSettings.RU.Settings)
+	require.EqualValues(t, 2_000_000, group.RUSettings.RU.Settings.FillRate)
+	require.EqualValues(t, 50_000_000_000, group.RUSettings.RU.Settings.BurstLimit)
+}
+
 func TestResourceGroupsControllerOptionsProvideDegradedFallback(t *testing.T) {
 	if kerneltype.IsNextGen() {
 		// Preserve the process-wide deploy mode because deploymode.IsStarter reads
@@ -130,11 +142,7 @@ func TestResourceGroupsControllerOptionsProvideDegradedFallback(t *testing.T) {
 	controllerWithFallback := newStarterControllerForTest(t, provider)
 	group, err := controllerWithFallback.GetResourceGroup("test-group")
 	require.NoError(t, err)
-	require.Equal(t, &rmpb.ResourceGroup{
-		Name:       "test-group",
-		Mode:       rmpb.GroupMode_RUMode,
-		RUSettings: newDefaultDegradedRUSettings(),
-	}, group)
+	requireDegradedResourceGroup(t, group, "test-group")
 
 	// The degraded group should not be cached. Once the provider recovers, the
 	// next lookup should observe the real resource-group metadata.
@@ -185,21 +193,13 @@ func TestStarterControllerGetResourceGroupUsesDegradedSettingsOnErrors(t *testin
 		require.NoError(t, deploymode.Set(originalDeployMode))
 	})
 
-	expectedGroup := func(name string) *rmpb.ResourceGroup {
-		return &rmpb.ResourceGroup{
-			Name:       name,
-			Mode:       rmpb.GroupMode_RUMode,
-			RUSettings: newDefaultDegradedRUSettings(),
-		}
-	}
-
 	t.Run("NotFound", func(t *testing.T) {
 		provider := newResourceGroupProviderStub(t, nil, rmclient.NewResourceGroupNotExistErr("missing-group"))
 		controller := newStarterControllerForTest(t, provider)
 
 		group, err := controller.GetResourceGroup("missing-group")
 		require.NoError(t, err)
-		require.Equal(t, expectedGroup("missing-group"), group)
+		requireDegradedResourceGroup(t, group, "missing-group")
 	})
 
 	t.Run("ContextCanceled", func(t *testing.T) {
@@ -208,7 +208,7 @@ func TestStarterControllerGetResourceGroupUsesDegradedSettingsOnErrors(t *testin
 
 		group, err := controller.GetResourceGroup("test-group")
 		require.NoError(t, err)
-		require.Equal(t, expectedGroup("test-group"), group)
+		requireDegradedResourceGroup(t, group, "test-group")
 	})
 
 	t.Run("GenericNonRetryableError", func(t *testing.T) {
@@ -217,7 +217,7 @@ func TestStarterControllerGetResourceGroupUsesDegradedSettingsOnErrors(t *testin
 
 		group, err := controller.GetResourceGroup("test-group")
 		require.NoError(t, err)
-		require.Equal(t, expectedGroup("test-group"), group)
+		requireDegradedResourceGroup(t, group, "test-group")
 	})
 }
 

From 59c011f16151db01b2527ae6dcb15915f7cfdb89 Mon Sep 17 00:00:00 2001
From: ystaticy <y_static_y@sina.com>
Date: Mon, 20 Jul 2026 16:44:01 +0800
Subject: [PATCH 16/21]  update pd client

Signed-off-by: ystaticy <y_static_y@sina.com>
---
 DEPS.bzl                   |  4 +--
 go.mod                     |  2 +-
 go.sum                     |  4 +--
 pkg/domain/BUILD.bazel     |  4 ++-
 pkg/domain/runaway_test.go | 71 ++++++++++----------------------------
 5 files changed, 27 insertions(+), 58 deletions(-)

diff --git a/DEPS.bzl b/DEPS.bzl
index 381bd2e9a9f28..30682100fc3cc 100644
--- a/DEPS.bzl
+++ b/DEPS.bzl
@@ -4207,8 +4207,8 @@ def go_deps():
         build_tags = ["nextgen", "intest"],
         build_file_proto_mode = "disable_global",
         importpath = "github.com/tikv/pd/client",
-        sum = "h1:OoBvgoeWmdNEXtS+eOlhysz/OvhA4GS0OdPVhTXteGA=",
-        version = "v0.0.0-20260708075407-4e05b9d2c2d3",
+        sum = "h1:BiPn4oLXVqB9ptPNmyo3rh/2IH1dTouXrrnneH86Z3M=",
+        version = "v0.0.0-20260720043438-0b37df9a48ed",
     )
     go_repository(
         name = "com_github_timakin_bodyclose",
diff --git a/go.mod b/go.mod
index e590aed6c5c42..179607ad82d4e 100644
--- a/go.mod
+++ b/go.mod
@@ -123,7 +123,7 @@ require (
 	github.com/stretchr/testify v1.11.1
 	github.com/tiancaiamao/appdash v0.0.0-20181126055449-889f96f722a2
 	github.com/tikv/client-go/v2 v2.0.8-0.20260708122311-01bd8f99f4da
-	github.com/tikv/pd/client v0.0.0-20260708075407-4e05b9d2c2d3
+	github.com/tikv/pd/client v0.0.0-20260720043438-0b37df9a48ed
 	github.com/timakin/bodyclose v0.0.0-20241222091800-1db5c5ca4d67
 	github.com/twmb/murmur3 v1.1.6
 	github.com/uber/jaeger-client-go v2.22.1+incompatible
diff --git a/go.sum b/go.sum
index a69dcfc6c875c..0440b05504932 100644
--- a/go.sum
+++ b/go.sum
@@ -902,8 +902,8 @@ github.com/tidwall/sjson v1.2.5 h1:kLy8mja+1c9jlljvWTlSazM7cKDRfJuR/bOJhcY5NcY=
 github.com/tidwall/sjson v1.2.5/go.mod h1:Fvgq9kS/6ociJEDnK0Fk1cpYF4FIW6ZF7LAe+6jwd28=
 github.com/tikv/client-go/v2 v2.0.8-0.20260708122311-01bd8f99f4da h1:Ju9uUKu3M5gPl7Z90e9dcGSe8LtXxGqvSetbPcr6tyc=
 github.com/tikv/client-go/v2 v2.0.8-0.20260708122311-01bd8f99f4da/go.mod h1:MRhIujZMMkYcI49Euif4+A3+SHSGwTpyUUadNz48R4g=
-github.com/tikv/pd/client v0.0.0-20260708075407-4e05b9d2c2d3 h1:OoBvgoeWmdNEXtS+eOlhysz/OvhA4GS0OdPVhTXteGA=
-github.com/tikv/pd/client v0.0.0-20260708075407-4e05b9d2c2d3/go.mod h1:3/Bu91CJONgkDA+Y0v/cnbROSJnu5tQ09vv7JGybUBA=
+github.com/tikv/pd/client v0.0.0-20260720043438-0b37df9a48ed h1:BiPn4oLXVqB9ptPNmyo3rh/2IH1dTouXrrnneH86Z3M=
+github.com/tikv/pd/client v0.0.0-20260720043438-0b37df9a48ed/go.mod h1:3/Bu91CJONgkDA+Y0v/cnbROSJnu5tQ09vv7JGybUBA=
 github.com/timakin/bodyclose v0.0.0-20241222091800-1db5c5ca4d67 h1:9LPGD+jzxMlnk5r6+hJnar67cgpDIz/iyD+rfl5r2Vk=
 github.com/timakin/bodyclose v0.0.0-20241222091800-1db5c5ca4d67/go.mod h1:mkjARE7Yr8qU23YcGMSALbIxTQ9r9QBVahQOBRfU460=
 github.com/tjfoc/gmsm v1.3.2/go.mod h1:HaUcFuY0auTiaHB9MHFGCPx5IaLhTUd2atbCFBQXn9w=
diff --git a/pkg/domain/BUILD.bazel b/pkg/domain/BUILD.bazel
index e3d3d26942457..8fbbc1674c6b2 100644
--- a/pkg/domain/BUILD.bazel
+++ b/pkg/domain/BUILD.bazel
@@ -157,7 +157,7 @@ go_test(
     ],
     embed = [":domain"],
     flaky = True,
-    shard_count = 34,
+    shard_count = 33,
     deps = [
         "//pkg/config",
         "//pkg/config/deploymode",
@@ -209,6 +209,8 @@ go_test(
         "@com_github_tikv_pd_client//opt",
         "@com_github_tikv_pd_client//resource_group/controller",
         "@io_etcd_go_etcd_tests_v3//integration",
+        "@org_golang_google_grpc//codes",
+        "@org_golang_google_grpc//status",
         "@org_uber_go_goleak//:goleak",
     ],
 )
diff --git a/pkg/domain/runaway_test.go b/pkg/domain/runaway_test.go
index dec2fe7a54e04..0b270489269f4 100644
--- a/pkg/domain/runaway_test.go
+++ b/pkg/domain/runaway_test.go
@@ -16,7 +16,6 @@ package domain
 
 import (
 	"context"
-	"errors"
 	"testing"
 	"time"
 
@@ -32,6 +31,8 @@ import (
 	pd "github.com/tikv/pd/client"
 	pderr "github.com/tikv/pd/client/errs"
 	rmclient "github.com/tikv/pd/client/resource_group/controller"
+	"google.golang.org/grpc/codes"
+	"google.golang.org/grpc/status"
 )
 
 type resourceGroupProviderStub struct {
@@ -88,8 +89,17 @@ func requireDegradedResourceGroup(t *testing.T, group *rmpb.ResourceGroup, name
 	require.NotNil(t, group.RUSettings)
 	require.NotNil(t, group.RUSettings.RU)
 	require.NotNil(t, group.RUSettings.RU.Settings)
-	require.EqualValues(t, 2_000_000, group.RUSettings.RU.Settings.FillRate)
-	require.EqualValues(t, 50_000_000_000, group.RUSettings.RU.Settings.BurstLimit)
+	require.EqualValues(t, defaultDegradedRUFillRate, group.RUSettings.RU.Settings.FillRate)
+	require.EqualValues(t, defaultDegradedRUBurstLimit, group.RUSettings.RU.Settings.BurstLimit)
+}
+
+func newTransientGetResourceGroupErr(name string) error {
+	err := status.Error(codes.Unavailable, "resource manager unavailable")
+	return &pderr.ErrClientGetResourceGroup{
+		ResourceGroupName: name,
+		Cause:             err.Error(),
+		Err:               err,
+	}
 }
 
 func TestResourceGroupsControllerOptionsProvideDegradedFallback(t *testing.T) {
@@ -113,10 +123,7 @@ func TestResourceGroupsControllerOptionsProvideDegradedFallback(t *testing.T) {
 				Settings: &rmpb.TokenLimitSettings{FillRate: 1},
 			},
 		},
-	}, &pderr.ErrClientGetResourceGroup{
-		ResourceGroupName: "test-group",
-		Cause:             "resource group unavailable",
-	})
+	}, newTransientGetResourceGroupErr("test-group"))
 
 	if !kerneltype.IsNextGen() {
 		controller, err := rmclient.NewResourceGroupController(
@@ -161,10 +168,7 @@ func TestResourceGroupsControllerOptionsProvideDegradedFallback(t *testing.T) {
 	require.Equal(t, provider.resourceGroup, group)
 
 	require.NoError(t, deploymode.Set(deploymode.Premium))
-	provider = newResourceGroupProviderStub(t, nil, &pderr.ErrClientGetResourceGroup{
-		ResourceGroupName: "test-group",
-		Cause:             "resource group unavailable",
-	})
+	provider = newResourceGroupProviderStub(t, nil, newTransientGetResourceGroupErr("test-group"))
 	controllerWithoutFallback, err := rmclient.NewResourceGroupController(
 		ctx,
 		2,
@@ -184,44 +188,7 @@ func TestResourceGroupsControllerOptionsProvideDegradedFallback(t *testing.T) {
 	require.Nil(t, group)
 }
 
-func TestStarterControllerGetResourceGroupUsesDegradedSettingsOnErrors(t *testing.T) {
-	if !kerneltype.IsNextGen() {
-		t.Skip("Starter deploy mode is only available in NextGen builds")
-	}
-	originalDeployMode := deploymode.Get()
-	t.Cleanup(func() {
-		require.NoError(t, deploymode.Set(originalDeployMode))
-	})
-
-	t.Run("NotFound", func(t *testing.T) {
-		provider := newResourceGroupProviderStub(t, nil, rmclient.NewResourceGroupNotExistErr("missing-group"))
-		controller := newStarterControllerForTest(t, provider)
-
-		group, err := controller.GetResourceGroup("missing-group")
-		require.NoError(t, err)
-		requireDegradedResourceGroup(t, group, "missing-group")
-	})
-
-	t.Run("ContextCanceled", func(t *testing.T) {
-		provider := newResourceGroupProviderStub(t, nil, context.Canceled)
-		controller := newStarterControllerForTest(t, provider)
-
-		group, err := controller.GetResourceGroup("test-group")
-		require.NoError(t, err)
-		requireDegradedResourceGroup(t, group, "test-group")
-	})
-
-	t.Run("GenericNonRetryableError", func(t *testing.T) {
-		provider := newResourceGroupProviderStub(t, nil, errors.New("invalid resource group lookup"))
-		controller := newStarterControllerForTest(t, provider)
-
-		group, err := controller.GetResourceGroup("test-group")
-		require.NoError(t, err)
-		requireDegradedResourceGroup(t, group, "test-group")
-	})
-}
-
-func TestStarterSwitchGroupUsesDegradedGroupOnLookupError(t *testing.T) {
+func TestStarterSwitchGroupUsesDegradedGroupOnTransientLookupError(t *testing.T) {
 	if !kerneltype.IsNextGen() {
 		t.Skip("Starter deploy mode is only available in NextGen builds")
 	}
@@ -230,7 +197,7 @@ func TestStarterSwitchGroupUsesDegradedGroupOnLookupError(t *testing.T) {
 		require.NoError(t, deploymode.Set(originalDeployMode))
 	})
 
-	provider := newResourceGroupProviderStub(t, nil, rmclient.NewResourceGroupNotExistErr("missing-switch-group"))
+	provider := newResourceGroupProviderStub(t, nil, newTransientGetResourceGroupErr("target-switch-group"))
 	controller := newStarterControllerForTest(t, provider)
 	manager := runaway.NewRunawayManager(controller, "127.0.0.1:4000", nil, make(chan struct{}), nil, nil)
 	t.Cleanup(manager.Stop)
@@ -239,7 +206,7 @@ func TestStarterSwitchGroupUsesDegradedGroupOnLookupError(t *testing.T) {
 		"source-group",
 		&rmpb.RunawaySettings{
 			Action:          rmpb.RunawayAction_SwitchGroup,
-			SwitchGroupName: "missing-switch-group",
+			SwitchGroupName: "target-switch-group",
 			Rule:            &rmpb.RunawayRule{ProcessedKeys: 1},
 		},
 		"SELECT 1",
@@ -255,7 +222,7 @@ func TestStarterSwitchGroupUsesDegradedGroupOnLookupError(t *testing.T) {
 		},
 	}
 	require.NoError(t, checker.BeforeCopRequest(req))
-	require.Equal(t, "missing-switch-group", req.GetResourceControlContext().GetResourceGroupName())
+	require.Equal(t, "target-switch-group", req.GetResourceControlContext().GetResourceGroupName())
 }
 
 func TestResourceGroupsControllerOptionsUseStarterPodNamespaceForVIPWaitRetry(t *testing.T) {

From 5e8359b3fd9f2565c681529109b0890875ed6fcf Mon Sep 17 00:00:00 2001
From: ystaticy <y_static_y@sina.com>
Date: Mon, 20 Jul 2026 17:50:18 +0800
Subject: [PATCH 17/21]  add config

Signed-off-by: ystaticy <y_static_y@sina.com>
---
 cmd/tidb-server/main.go                       |  16 ++-
 cmd/tidb-server/main_test.go                  |   9 +-
 pkg/config/config.go                          |   3 +
 pkg/domain/BUILD.bazel                        |   1 +
 .../resource_group_controller_options.go      |   7 +-
 pkg/domain/runaway_test.go                    | 110 +++++++++++++++---
 6 files changed, 116 insertions(+), 30 deletions(-)

diff --git a/cmd/tidb-server/main.go b/cmd/tidb-server/main.go
index 5102accf8c6f3..8cafdf07a8092 100644
--- a/cmd/tidb-server/main.go
+++ b/cmd/tidb-server/main.go
@@ -1351,10 +1351,11 @@ func prepareKeyspaceObservabilityForStarter(metadata map[string]string) error {
 }
 
 type starterParams struct {
-	managerNamespace string
-	podName          string
-	podIP            string
-	podNamespace     string
+	managerNamespace               string
+	podName                        string
+	podIP                          string
+	podNamespace                   string
+	enableGetResourceGroupDegraded bool
 }
 
 func parseStarterAdditionalParams(raw string) (starterParams, error) {
@@ -1397,6 +1398,12 @@ func parseStarterAdditionalParams(raw string) (starterParams, error) {
 			params.podIP = value
 		case "pod-namespace":
 			params.podNamespace = value
+		case "enable-get-resource-group-degraded":
+			enable, err := strconv.ParseBool(value)
+			if err != nil {
+				return params, fmt.Errorf("starter additional param %q must be a bool: %w", key, err)
+			}
+			params.enableGetResourceGroupDegraded = enable
 		default:
 			return params, fmt.Errorf("unknown starter additional param %q", key)
 		}
@@ -1413,6 +1420,7 @@ func applyStarterAdditionalParams(cfg *config.Config, raw string) error {
 	cfg.StarterParams.PodName = params.podName
 	cfg.StarterParams.PodIP = params.podIP
 	cfg.StarterParams.PodNamespace = params.podNamespace
+	cfg.StarterParams.EnableGetResourceGroupDegraded = params.enableGetResourceGroupDegraded
 	return nil
 }
 
diff --git a/cmd/tidb-server/main_test.go b/cmd/tidb-server/main_test.go
index 50f5e0d5bf8de..317e2ac8d75ab 100644
--- a/cmd/tidb-server/main_test.go
+++ b/cmd/tidb-server/main_test.go
@@ -85,7 +85,7 @@ func TestOverrideConfigKeyspaceActivateMode(t *testing.T) {
 	fset := initFlagSet()
 	require.NoError(t, fset.Parse([]string{
 		"--keyspace-activate=true",
-		"--starter-additional-params=pod-name=pod-1,pod-ip=10.0.0.1,pod-namespace=ns-1",
+		"--starter-additional-params=pod-name=pod-1,pod-ip=10.0.0.1,pod-namespace=ns-1,enable-get-resource-group-degraded=true",
 	}))
 
 	cfg := config.NewConfig()
@@ -95,7 +95,8 @@ func TestOverrideConfigKeyspaceActivateMode(t *testing.T) {
 	require.Equal(t, "pod-1", cfg.StarterParams.PodName)
 	require.Equal(t, "10.0.0.1", cfg.StarterParams.PodIP)
 	require.Equal(t, "ns-1", cfg.StarterParams.PodNamespace)
-	require.Equal(t, "pod-name=pod-1,pod-ip=10.0.0.1,pod-namespace=ns-1", *starterAdditionalParams)
+	require.True(t, cfg.StarterParams.EnableGetResourceGroupDegraded)
+	require.Equal(t, "pod-name=pod-1,pod-ip=10.0.0.1,pod-namespace=ns-1,enable-get-resource-group-degraded=true", *starterAdditionalParams)
 }
 
 func TestSetGlobalVars(t *testing.T) {
@@ -225,6 +226,10 @@ func TestCreateMgrClientRequiresPodIdentityInStarter(t *testing.T) {
 	err = applyStarterAdditionalParams(config.GetGlobalConfig(), unknownParam)
 	require.ErrorContains(t, err, `unknown starter additional param "unknown"`)
 
+	invalidBoolParam := "enable-get-resource-group-degraded=definitely"
+	err = applyStarterAdditionalParams(config.GetGlobalConfig(), invalidBoolParam)
+	require.ErrorContains(t, err, `starter additional param "enable-get-resource-group-degraded" must be a bool`)
+
 	config.UpdateGlobal(func(conf *config.Config) {
 		conf.StarterParams.ManagerAddr = ""
 		conf.StarterParams.ManagerNamespace = ""
diff --git a/pkg/config/config.go b/pkg/config/config.go
index 8d3236bbf3895..63c3fb917c588 100644
--- a/pkg/config/config.go
+++ b/pkg/config/config.go
@@ -1106,6 +1106,9 @@ type StarterParams struct {
 	// PodNamespace captures the runtime pod namespace from --starter-additional-params.
 	// It is command-line derived runtime metadata rather than file-backed config.
 	PodNamespace string `toml:"-" json:"-"`
+	// EnableGetResourceGroupDegraded enables degraded GetResourceGroup handling for resource control.
+	// It is command-line derived runtime metadata rather than file-backed config.
+	EnableGetResourceGroupDegraded bool `toml:"-" json:"-"`
 	// MaxImportDataSize is the maximum total real source data size allowed for IMPORT INTO.
 	// Zero means unlimited.
 	MaxImportDataSize configtypes.ByteSize `toml:"max-import-data-size" json:"max-import-data-size,omitempty"`
diff --git a/pkg/domain/BUILD.bazel b/pkg/domain/BUILD.bazel
index 8fbbc1674c6b2..f6804d4b65a2d 100644
--- a/pkg/domain/BUILD.bazel
+++ b/pkg/domain/BUILD.bazel
@@ -198,6 +198,7 @@ go_test(
         "@com_github_pingcap_errors//:errors",
         "@com_github_pingcap_failpoint//:failpoint",
         "@com_github_pingcap_kvproto//pkg/kvrpcpb",
+        "@com_github_pingcap_kvproto//pkg/meta_storagepb",
         "@com_github_pingcap_kvproto//pkg/metapb",
         "@com_github_pingcap_kvproto//pkg/resource_manager",
         "@com_github_prometheus_client_model//go",
diff --git a/pkg/domain/resource_group_controller_options.go b/pkg/domain/resource_group_controller_options.go
index 5df7a378f75a8..ada7a0640cdcb 100644
--- a/pkg/domain/resource_group_controller_options.go
+++ b/pkg/domain/resource_group_controller_options.go
@@ -15,7 +15,6 @@
 package domain
 
 import (
-	"strings"
 	"time"
 
 	rmpb "github.com/pingcap/kvproto/pkg/resource_manager"
@@ -48,16 +47,12 @@ func newResourceGroupsControllerOptions() []rmclient.ResourceControlCreateOption
 	opts := []rmclient.ResourceControlCreateOption{
 		rmclient.WithMaxWaitDuration(runaway.MaxWaitDuration),
 	}
-	if deploymode.IsStarter() {
+	if deploymode.IsStarter() && config.GetGlobalConfig().StarterParams.EnableGetResourceGroupDegraded {
 		opts = append(opts,
 			// Keep degraded-group synthesis inside the controller so degraded
 			// resource groups are not inserted into the controller cache.
 			rmclient.WithDegradedRUSettings(newDefaultDegradedRUSettings()),
 			rmclient.WithDegradedModeWaitDuration(defaultDegradedModeWaitTimeout),
-		)
-	}
-	if strings.Contains(config.GetGlobalConfig().StarterParams.PodNamespace, "vip") {
-		opts = append(opts,
 			rmclient.WithWaitRetryInterval(tokenWaitRetryInterval),
 			rmclient.WithWaitRetryTimes(tokenWaitRetryTimes),
 		)
diff --git a/pkg/domain/runaway_test.go b/pkg/domain/runaway_test.go
index 0b270489269f4..1859791a55fa4 100644
--- a/pkg/domain/runaway_test.go
+++ b/pkg/domain/runaway_test.go
@@ -16,10 +16,12 @@ package domain
 
 import (
 	"context"
+	"encoding/json"
 	"testing"
 	"time"
 
 	"github.com/pingcap/kvproto/pkg/kvrpcpb"
+	"github.com/pingcap/kvproto/pkg/meta_storagepb"
 	rmpb "github.com/pingcap/kvproto/pkg/resource_manager"
 	"github.com/pingcap/tidb/pkg/config"
 	"github.com/pingcap/tidb/pkg/config/deploymode"
@@ -30,6 +32,7 @@ import (
 	"github.com/tikv/client-go/v2/tikvrpc"
 	pd "github.com/tikv/pd/client"
 	pderr "github.com/tikv/pd/client/errs"
+	"github.com/tikv/pd/client/opt"
 	rmclient "github.com/tikv/pd/client/resource_group/controller"
 	"google.golang.org/grpc/codes"
 	"google.golang.org/grpc/status"
@@ -37,8 +40,9 @@ import (
 
 type resourceGroupProviderStub struct {
 	rmclient.ResourceGroupProvider
-	resourceGroup *rmpb.ResourceGroup
-	resourceErr   error
+	resourceGroup    *rmpb.ResourceGroup
+	resourceErr      error
+	controllerConfig *rmclient.Config
 }
 
 func newResourceGroupProviderStub(t *testing.T, resourceGroup *rmpb.ResourceGroup, resourceErr error) *resourceGroupProviderStub {
@@ -59,6 +63,22 @@ func (s *resourceGroupProviderStub) GetResourceGroup(context.Context, string, ..
 	return s.resourceGroup, s.resourceErr
 }
 
+func (s *resourceGroupProviderStub) Get(ctx context.Context, key []byte, opts ...opt.MetaStorageOption) (*meta_storagepb.GetResponse, error) {
+	if s.controllerConfig == nil {
+		return s.ResourceGroupProvider.Get(ctx, key, opts...)
+	}
+	value, err := json.Marshal(s.controllerConfig)
+	if err != nil {
+		return nil, err
+	}
+	return &meta_storagepb.GetResponse{
+		Kvs: []*meta_storagepb.KeyValue{{
+			Key:   key,
+			Value: value,
+		}},
+	}, nil
+}
+
 func newStarterControllerForTest(t *testing.T, provider rmclient.ResourceGroupProvider) *rmclient.ResourceGroupsController {
 	t.Helper()
 	ctx, cancel := context.WithCancel(context.Background())
@@ -103,6 +123,8 @@ func newTransientGetResourceGroupErr(name string) error {
 }
 
 func TestResourceGroupsControllerOptionsProvideDegradedFallback(t *testing.T) {
+	restoreConfig := config.RestoreFunc()
+	t.Cleanup(restoreConfig)
 	if kerneltype.IsNextGen() {
 		// Preserve the process-wide deploy mode because deploymode.IsStarter reads
 		// it directly when newResourceGroupsControllerOptions builds controller options.
@@ -146,6 +168,9 @@ func TestResourceGroupsControllerOptionsProvideDegradedFallback(t *testing.T) {
 		return
 	}
 
+	config.UpdateGlobal(func(conf *config.Config) {
+		conf.StarterParams.EnableGetResourceGroupDegraded = true
+	})
 	controllerWithFallback := newStarterControllerForTest(t, provider)
 	group, err := controllerWithFallback.GetResourceGroup("test-group")
 	require.NoError(t, err)
@@ -192,11 +217,16 @@ func TestStarterSwitchGroupUsesDegradedGroupOnTransientLookupError(t *testing.T)
 	if !kerneltype.IsNextGen() {
 		t.Skip("Starter deploy mode is only available in NextGen builds")
 	}
+	restoreConfig := config.RestoreFunc()
+	t.Cleanup(restoreConfig)
 	originalDeployMode := deploymode.Get()
 	t.Cleanup(func() {
 		require.NoError(t, deploymode.Set(originalDeployMode))
 	})
 
+	config.UpdateGlobal(func(conf *config.Config) {
+		conf.StarterParams.EnableGetResourceGroupDegraded = true
+	})
 	provider := newResourceGroupProviderStub(t, nil, newTransientGetResourceGroupErr("target-switch-group"))
 	controller := newStarterControllerForTest(t, provider)
 	manager := runaway.NewRunawayManager(controller, "127.0.0.1:4000", nil, make(chan struct{}), nil, nil)
@@ -225,28 +255,72 @@ func TestStarterSwitchGroupUsesDegradedGroupOnTransientLookupError(t *testing.T)
 	require.Equal(t, "target-switch-group", req.GetResourceControlContext().GetResourceGroupName())
 }
 
-func TestResourceGroupsControllerOptionsUseStarterPodNamespaceForVIPWaitRetry(t *testing.T) {
+func TestResourceGroupsControllerOptionsUseExplicitGetResourceGroupDegraded(t *testing.T) {
+	if !kerneltype.IsNextGen() {
+		t.Skip("Starter deploy mode is only available in NextGen builds")
+	}
 	restoreConfig := config.RestoreFunc()
 	t.Cleanup(restoreConfig)
-	vipOptionCount := 3
-	standardOptionCount := 1
-	if kerneltype.IsNextGen() {
-		originalDeployMode := deploymode.Get()
-		t.Cleanup(func() {
-			require.NoError(t, deploymode.Set(originalDeployMode))
+	originalDeployMode := deploymode.Get()
+	t.Cleanup(func() {
+		require.NoError(t, deploymode.Set(originalDeployMode))
+	})
+
+	newController := func(t *testing.T) *rmclient.ResourceGroupsController {
+		t.Helper()
+		provider := newResourceGroupProviderStub(t, nil, nil)
+		provider.controllerConfig = rmclient.DefaultConfig()
+		provider.controllerConfig.WaitRetryInterval = rmclient.NewDuration(250 * time.Millisecond)
+		provider.controllerConfig.WaitRetryTimes = 4
+		provider.controllerConfig.LTBTokenRPCMaxDelay = rmclient.NewDuration(time.Second)
+
+		controller, err := rmclient.NewResourceGroupController(
+			context.Background(),
+			1,
+			provider,
+			nil,
+			0,
+			newResourceGroupsControllerOptions()...,
+		)
+		require.NoError(t, err)
+		return controller
+	}
+
+	t.Run("enabled explicitly in starter", func(t *testing.T) {
+		require.NoError(t, deploymode.Set(deploymode.Starter))
+		config.UpdateGlobal(func(conf *config.Config) {
+			conf.StarterParams.PodNamespace = "starter-standard-ns"
+			conf.StarterParams.EnableGetResourceGroupDegraded = true
 		})
+
+		ruConfig := newController(t).GetConfig()
+		require.Equal(t, tokenWaitRetryInterval, ruConfig.WaitRetryInterval)
+		require.Equal(t, tokenWaitRetryTimes, ruConfig.WaitRetryTimes)
+		require.Equal(t, defaultDegradedModeWaitTimeout, ruConfig.DegradedModeWaitDuration)
+	})
+
+	t.Run("namespace alone does not enable degraded mode", func(t *testing.T) {
 		require.NoError(t, deploymode.Set(deploymode.Starter))
-		vipOptionCount = 5
-		standardOptionCount = 3
-	}
+		config.UpdateGlobal(func(conf *config.Config) {
+			conf.StarterParams.PodNamespace = "starter-vip-ns"
+			conf.StarterParams.EnableGetResourceGroupDegraded = false
+		})
 
-	config.UpdateGlobal(func(conf *config.Config) {
-		conf.StarterParams.PodNamespace = "starter-vip-ns"
+		ruConfig := newController(t).GetConfig()
+		require.Equal(t, 250*time.Millisecond, ruConfig.WaitRetryInterval)
+		require.Equal(t, 4, ruConfig.WaitRetryTimes)
+		require.Zero(t, ruConfig.DegradedModeWaitDuration)
 	})
-	require.Len(t, newResourceGroupsControllerOptions(), vipOptionCount)
 
-	config.UpdateGlobal(func(conf *config.Config) {
-		conf.StarterParams.PodNamespace = "starter-standard-ns"
+	t.Run("ignored outside starter", func(t *testing.T) {
+		require.NoError(t, deploymode.Set(deploymode.Premium))
+		config.UpdateGlobal(func(conf *config.Config) {
+			conf.StarterParams.EnableGetResourceGroupDegraded = true
+		})
+
+		ruConfig := newController(t).GetConfig()
+		require.Equal(t, 250*time.Millisecond, ruConfig.WaitRetryInterval)
+		require.Equal(t, 4, ruConfig.WaitRetryTimes)
+		require.Zero(t, ruConfig.DegradedModeWaitDuration)
 	})
-	require.Len(t, newResourceGroupsControllerOptions(), standardOptionCount)
 }

From 87fec4d3bfdb737c63407ada9aeffaaa23153ec6 Mon Sep 17 00:00:00 2001
From: ystaticy <y_static_y@sina.com>
Date: Mon, 20 Jul 2026 18:07:26 +0800
Subject: [PATCH 18/21]  fix discussion_r3586340548

Signed-off-by: ystaticy <y_static_y@sina.com>
---
 pkg/domain/runaway_test.go | 204 ++++++++++++++++---------------------
 1 file changed, 85 insertions(+), 119 deletions(-)

diff --git a/pkg/domain/runaway_test.go b/pkg/domain/runaway_test.go
index 1859791a55fa4..e0cf6861a5462 100644
--- a/pkg/domain/runaway_test.go
+++ b/pkg/domain/runaway_test.go
@@ -122,64 +122,24 @@ func newTransientGetResourceGroupErr(name string) error {
 	}
 }
 
-func TestResourceGroupsControllerOptionsProvideDegradedFallback(t *testing.T) {
+func restoreResourceGroupControllerTestState(t *testing.T) {
+	t.Helper()
 	restoreConfig := config.RestoreFunc()
 	t.Cleanup(restoreConfig)
-	if kerneltype.IsNextGen() {
-		// Preserve the process-wide deploy mode because deploymode.IsStarter reads
-		// it directly when newResourceGroupsControllerOptions builds controller options.
-		originalDeployMode := deploymode.Get()
-		t.Cleanup(func() {
-			require.NoError(t, deploymode.Set(originalDeployMode))
-		})
-	}
-
-	ctx, cancel := context.WithCancel(context.Background())
-	defer cancel()
-
-	provider := newResourceGroupProviderStub(t, &rmpb.ResourceGroup{
-		Name: "test-group",
-		Mode: rmpb.GroupMode_RUMode,
-		RUSettings: &rmpb.GroupRequestUnitSettings{
-			RU: &rmpb.TokenBucket{
-				Settings: &rmpb.TokenLimitSettings{FillRate: 1},
-			},
-		},
-	}, newTransientGetResourceGroupErr("test-group"))
-
 	if !kerneltype.IsNextGen() {
-		controller, err := rmclient.NewResourceGroupController(
-			ctx,
-			1,
-			provider,
-			nil,
-			0,
-			newResourceGroupsControllerOptions()...,
-		)
-		require.NoError(t, err)
-		controller.Start(ctx)
-		defer func() {
-			require.NoError(t, controller.Stop())
-		}()
-
-		group, err := controller.GetResourceGroup("test-group")
-		require.Error(t, err)
-		require.Nil(t, group)
 		return
 	}
-
-	config.UpdateGlobal(func(conf *config.Config) {
-		conf.StarterParams.EnableGetResourceGroupDegraded = true
+	// Preserve the process-wide deploy mode because deploymode.IsStarter reads
+	// it directly when newResourceGroupsControllerOptions builds controller options.
+	originalDeployMode := deploymode.Get()
+	t.Cleanup(func() {
+		require.NoError(t, deploymode.Set(originalDeployMode))
 	})
-	controllerWithFallback := newStarterControllerForTest(t, provider)
-	group, err := controllerWithFallback.GetResourceGroup("test-group")
-	require.NoError(t, err)
-	requireDegradedResourceGroup(t, group, "test-group")
+}
 
-	// The degraded group should not be cached. Once the provider recovers, the
-	// next lookup should observe the real resource-group metadata.
-	provider.resourceGroup = &rmpb.ResourceGroup{
-		Name: "test-group",
+func newTestResourceGroup(name string) *rmpb.ResourceGroup {
+	return &rmpb.ResourceGroup{
+		Name: name,
 		Mode: rmpb.GroupMode_RUMode,
 		RUSettings: &rmpb.GroupRequestUnitSettings{
 			RU: &rmpb.TokenBucket{
@@ -187,84 +147,50 @@ func TestResourceGroupsControllerOptionsProvideDegradedFallback(t *testing.T) {
 			},
 		},
 	}
-	provider.resourceErr = nil
-	group, err = controllerWithFallback.GetResourceGroup("test-group")
-	require.NoError(t, err)
-	require.Equal(t, provider.resourceGroup, group)
-
-	require.NoError(t, deploymode.Set(deploymode.Premium))
-	provider = newResourceGroupProviderStub(t, nil, newTransientGetResourceGroupErr("test-group"))
-	controllerWithoutFallback, err := rmclient.NewResourceGroupController(
-		ctx,
-		2,
-		provider,
-		nil,
-		0,
-		newResourceGroupsControllerOptions()...,
-	)
-	require.NoError(t, err)
-	controllerWithoutFallback.Start(ctx)
-	defer func() {
-		require.NoError(t, controllerWithoutFallback.Stop())
-	}()
-
-	group, err = controllerWithoutFallback.GetResourceGroup("test-group")
-	require.Error(t, err)
-	require.Nil(t, group)
 }
 
-func TestStarterSwitchGroupUsesDegradedGroupOnTransientLookupError(t *testing.T) {
+func TestStarterDegradedResourceGroup(t *testing.T) {
 	if !kerneltype.IsNextGen() {
 		t.Skip("Starter deploy mode is only available in NextGen builds")
 	}
-	restoreConfig := config.RestoreFunc()
-	t.Cleanup(restoreConfig)
-	originalDeployMode := deploymode.Get()
-	t.Cleanup(func() {
-		require.NoError(t, deploymode.Set(originalDeployMode))
-	})
 
-	config.UpdateGlobal(func(conf *config.Config) {
-		conf.StarterParams.EnableGetResourceGroupDegraded = true
+	t.Run("fallback", func(t *testing.T) {
+		restoreResourceGroupControllerTestState(t)
+		config.UpdateGlobal(func(conf *config.Config) {
+			conf.StarterParams.EnableGetResourceGroupDegraded = true
+		})
+
+		provider := newResourceGroupProviderStub(t, nil, newTransientGetResourceGroupErr("test-group"))
+		controller := newStarterControllerForTest(t, provider)
+		group, err := controller.GetResourceGroup("test-group")
+		require.NoError(t, err)
+		requireDegradedResourceGroup(t, group, "test-group")
 	})
-	provider := newResourceGroupProviderStub(t, nil, newTransientGetResourceGroupErr("target-switch-group"))
-	controller := newStarterControllerForTest(t, provider)
-	manager := runaway.NewRunawayManager(controller, "127.0.0.1:4000", nil, make(chan struct{}), nil, nil)
-	t.Cleanup(manager.Stop)
-	checker := runaway.NewChecker(
-		manager,
-		"source-group",
-		&rmpb.RunawaySettings{
-			Action:          rmpb.RunawayAction_SwitchGroup,
-			SwitchGroupName: "target-switch-group",
-			Rule:            &rmpb.RunawayRule{ProcessedKeys: 1},
-		},
-		"SELECT 1",
-		"sql_digest",
-		"plan_digest",
-		time.Now(),
-	)
 
-	require.NoError(t, checker.CheckThresholds(nil, 10, nil))
-	req := &tikvrpc.Request{
-		Context: kvrpcpb.Context{
-			ResourceControlContext: &kvrpcpb.ResourceControlContext{},
-		},
-	}
-	require.NoError(t, checker.BeforeCopRequest(req))
-	require.Equal(t, "target-switch-group", req.GetResourceControlContext().GetResourceGroupName())
+	t.Run("recovery does not cache degraded group", func(t *testing.T) {
+		restoreResourceGroupControllerTestState(t)
+		config.UpdateGlobal(func(conf *config.Config) {
+			conf.StarterParams.EnableGetResourceGroupDegraded = true
+		})
+
+		provider := newResourceGroupProviderStub(t, nil, newTransientGetResourceGroupErr("test-group"))
+		controller := newStarterControllerForTest(t, provider)
+		group, err := controller.GetResourceGroup("test-group")
+		require.NoError(t, err)
+		requireDegradedResourceGroup(t, group, "test-group")
+
+		provider.resourceGroup = newTestResourceGroup("test-group")
+		provider.resourceErr = nil
+		group, err = controller.GetResourceGroup("test-group")
+		require.NoError(t, err)
+		require.Equal(t, provider.resourceGroup, group)
+	})
 }
 
-func TestResourceGroupsControllerOptionsUseExplicitGetResourceGroupDegraded(t *testing.T) {
+func TestResourceGroupsControllerOptions(t *testing.T) {
 	if !kerneltype.IsNextGen() {
 		t.Skip("Starter deploy mode is only available in NextGen builds")
 	}
-	restoreConfig := config.RestoreFunc()
-	t.Cleanup(restoreConfig)
-	originalDeployMode := deploymode.Get()
-	t.Cleanup(func() {
-		require.NoError(t, deploymode.Set(originalDeployMode))
-	})
 
 	newController := func(t *testing.T) *rmclient.ResourceGroupsController {
 		t.Helper()
@@ -286,7 +212,8 @@ func TestResourceGroupsControllerOptionsUseExplicitGetResourceGroupDegraded(t *t
 		return controller
 	}
 
-	t.Run("enabled explicitly in starter", func(t *testing.T) {
+	t.Run("starter enables degraded mode explicitly", func(t *testing.T) {
+		restoreResourceGroupControllerTestState(t)
 		require.NoError(t, deploymode.Set(deploymode.Starter))
 		config.UpdateGlobal(func(conf *config.Config) {
 			conf.StarterParams.PodNamespace = "starter-standard-ns"
@@ -299,7 +226,8 @@ func TestResourceGroupsControllerOptionsUseExplicitGetResourceGroupDegraded(t *t
 		require.Equal(t, defaultDegradedModeWaitTimeout, ruConfig.DegradedModeWaitDuration)
 	})
 
-	t.Run("namespace alone does not enable degraded mode", func(t *testing.T) {
+	t.Run("starter namespace alone does not enable degraded mode", func(t *testing.T) {
+		restoreResourceGroupControllerTestState(t)
 		require.NoError(t, deploymode.Set(deploymode.Starter))
 		config.UpdateGlobal(func(conf *config.Config) {
 			conf.StarterParams.PodNamespace = "starter-vip-ns"
@@ -312,7 +240,8 @@ func TestResourceGroupsControllerOptionsUseExplicitGetResourceGroupDegraded(t *t
 		require.Zero(t, ruConfig.DegradedModeWaitDuration)
 	})
 
-	t.Run("ignored outside starter", func(t *testing.T) {
+	t.Run("non starter ignores degraded flag", func(t *testing.T) {
+		restoreResourceGroupControllerTestState(t)
 		require.NoError(t, deploymode.Set(deploymode.Premium))
 		config.UpdateGlobal(func(conf *config.Config) {
 			conf.StarterParams.EnableGetResourceGroupDegraded = true
@@ -324,3 +253,40 @@ func TestResourceGroupsControllerOptionsUseExplicitGetResourceGroupDegraded(t *t
 		require.Zero(t, ruConfig.DegradedModeWaitDuration)
 	})
 }
+
+func TestStarterRunawaySwitchGroup(t *testing.T) {
+	if !kerneltype.IsNextGen() {
+		t.Skip("Starter deploy mode is only available in NextGen builds")
+	}
+	restoreResourceGroupControllerTestState(t)
+
+	config.UpdateGlobal(func(conf *config.Config) {
+		conf.StarterParams.EnableGetResourceGroupDegraded = true
+	})
+	provider := newResourceGroupProviderStub(t, nil, newTransientGetResourceGroupErr("target-switch-group"))
+	controller := newStarterControllerForTest(t, provider)
+	manager := runaway.NewRunawayManager(controller, "127.0.0.1:4000", nil, make(chan struct{}), nil, nil)
+	t.Cleanup(manager.Stop)
+	checker := runaway.NewChecker(
+		manager,
+		"source-group",
+		&rmpb.RunawaySettings{
+			Action:          rmpb.RunawayAction_SwitchGroup,
+			SwitchGroupName: "target-switch-group",
+			Rule:            &rmpb.RunawayRule{ProcessedKeys: 1},
+		},
+		"SELECT 1",
+		"sql_digest",
+		"plan_digest",
+		time.Now(),
+	)
+
+	require.NoError(t, checker.CheckThresholds(nil, 10, nil))
+	req := &tikvrpc.Request{
+		Context: kvrpcpb.Context{
+			ResourceControlContext: &kvrpcpb.ResourceControlContext{},
+		},
+	}
+	require.NoError(t, checker.BeforeCopRequest(req))
+	require.Equal(t, "target-switch-group", req.GetResourceControlContext().GetResourceGroupName())
+}

From 16506f75a5dc38ca29de6e562c52d1bbfb708a3c Mon Sep 17 00:00:00 2001
From: ystaticy <y_static_y@sina.com>
Date: Tue, 21 Jul 2026 15:14:29 +0800
Subject: [PATCH 19/21]  add code comments

Signed-off-by: ystaticy <y_static_y@sina.com>
---
 pkg/domain/resource_group_controller_options.go | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/pkg/domain/resource_group_controller_options.go b/pkg/domain/resource_group_controller_options.go
index ada7a0640cdcb..8cf38c2c2644e 100644
--- a/pkg/domain/resource_group_controller_options.go
+++ b/pkg/domain/resource_group_controller_options.go
@@ -49,8 +49,13 @@ func newResourceGroupsControllerOptions() []rmclient.ResourceControlCreateOption
 	}
 	if deploymode.IsStarter() && config.GetGlobalConfig().StarterParams.EnableGetResourceGroupDegraded {
 		opts = append(opts,
-			// Keep degraded-group synthesis inside the controller so degraded
-			// resource groups are not inserted into the controller cache.
+			// This Starter-only degraded path is a best-effort UX fallback for
+			// temporary GetResourceGroup failures. It provides a permissive
+			// group so user requests do not fail immediately; it is not intended
+			// to define a precise cross-RPC RU limit or response-side accounting
+			// contract while resource manager is unavailable. Keep synthesis
+			// inside the controller so degraded groups are not inserted into the
+			// normal metadata cache.
 			rmclient.WithDegradedRUSettings(newDefaultDegradedRUSettings()),
 			rmclient.WithDegradedModeWaitDuration(defaultDegradedModeWaitTimeout),
 			rmclient.WithWaitRetryInterval(tokenWaitRetryInterval),

From 606f1bf76b942cc62062df5aada2988af8b6f8ea Mon Sep 17 00:00:00 2001
From: ystaticy <y_static_y@sina.com>
Date: Tue, 21 Jul 2026 15:39:46 +0800
Subject: [PATCH 20/21]  remove unused code

Signed-off-by: ystaticy <y_static_y@sina.com>
---
 cmd/tidb-server/main.go      | 17 +++++++++--------
 cmd/tidb-server/main_test.go | 26 ++++++++------------------
 pkg/config/config.go         | 14 +-------------
 pkg/domain/runaway_test.go   |  4 +---
 4 files changed, 19 insertions(+), 42 deletions(-)

diff --git a/cmd/tidb-server/main.go b/cmd/tidb-server/main.go
index 8cafdf07a8092..b9476df7fdbf7 100644
--- a/cmd/tidb-server/main.go
+++ b/cmd/tidb-server/main.go
@@ -1416,10 +1416,6 @@ func applyStarterAdditionalParams(cfg *config.Config, raw string) error {
 	if err != nil {
 		return err
 	}
-	cfg.StarterParams.ManagerNamespace = params.managerNamespace
-	cfg.StarterParams.PodName = params.podName
-	cfg.StarterParams.PodIP = params.podIP
-	cfg.StarterParams.PodNamespace = params.podNamespace
 	cfg.StarterParams.EnableGetResourceGroupDegraded = params.enableGetResourceGroupDegraded
 	return nil
 }
@@ -1447,18 +1443,23 @@ func createMgrClientForStarter() (tidbmanager.Client, error) {
 		return nil, err
 	}
 
+	params, err := parseStarterAdditionalParams(getStarterAdditionalParams())
+	if err != nil {
+		return nil, err
+	}
+
 	managerAddr := cfg.StarterParams.ManagerAddr
 	if managerAddr == "" {
-		managerNs := cfg.StarterParams.ManagerNamespace
+		managerNs := params.managerNamespace
 		if managerNs == "" {
 			return nil, fmt.Errorf("manager notifier requires manager-addr config or manager-namespace in --starter-additional-params")
 		}
 		managerAddr = fmt.Sprintf("manager-server.%s.svc:8000", managerNs)
 	}
 
-	podName := cfg.StarterParams.PodName
-	podIP := cfg.StarterParams.PodIP
-	namespace := cfg.StarterParams.PodNamespace
+	podName := params.podName
+	podIP := params.podIP
+	namespace := params.podNamespace
 	if podName == "" || podIP == "" || namespace == "" {
 		return nil, fmt.Errorf("manager notifier requires --starter-additional-params with pod-name, pod-ip and pod-namespace: pod-name=%q, pod-ip=%q, pod-namespace=%q",
 			podName, podIP, namespace)
diff --git a/cmd/tidb-server/main_test.go b/cmd/tidb-server/main_test.go
index 317e2ac8d75ab..67b6ff9201039 100644
--- a/cmd/tidb-server/main_test.go
+++ b/cmd/tidb-server/main_test.go
@@ -92,9 +92,6 @@ func TestOverrideConfigKeyspaceActivateMode(t *testing.T) {
 	cfg.DeployMode = deploymode.Starter
 	overrideConfig(cfg, fset)
 	require.True(t, cfg.KeyspaceActivateMode)
-	require.Equal(t, "pod-1", cfg.StarterParams.PodName)
-	require.Equal(t, "10.0.0.1", cfg.StarterParams.PodIP)
-	require.Equal(t, "ns-1", cfg.StarterParams.PodNamespace)
 	require.True(t, cfg.StarterParams.EnableGetResourceGroupDegraded)
 	require.Equal(t, "pod-name=pod-1,pod-ip=10.0.0.1,pod-namespace=ns-1,enable-get-resource-group-degraded=true", *starterAdditionalParams)
 }
@@ -213,37 +210,30 @@ func TestCreateMgrClientRequiresPodIdentityInStarter(t *testing.T) {
 	require.ErrorContains(t, err, "manager notifier requires --starter-additional-params")
 
 	duplicatedParam := "pod-name=pod-1,pod-name=pod-2,pod-ip=10.0.0.1,pod-namespace=ns-1"
-	config.UpdateGlobal(func(conf *config.Config) {
-		conf.StarterParams.ManagerNamespace = ""
-		conf.StarterParams.PodName = ""
-		conf.StarterParams.PodIP = ""
-		conf.StarterParams.PodNamespace = ""
-	})
-	err = applyStarterAdditionalParams(config.GetGlobalConfig(), duplicatedParam)
+	starterAdditionalParams = &duplicatedParam
+	_, err = createMgrClientForStarter()
 	require.ErrorContains(t, err, `starter additional param "pod-name" is duplicated`)
 
 	unknownParam := "pod-name=pod-1,pod-ip=10.0.0.1,pod-namespace=ns-1,unknown=value"
-	err = applyStarterAdditionalParams(config.GetGlobalConfig(), unknownParam)
+	starterAdditionalParams = &unknownParam
+	_, err = createMgrClientForStarter()
 	require.ErrorContains(t, err, `unknown starter additional param "unknown"`)
 
 	invalidBoolParam := "enable-get-resource-group-degraded=definitely"
-	err = applyStarterAdditionalParams(config.GetGlobalConfig(), invalidBoolParam)
+	starterAdditionalParams = &invalidBoolParam
+	_, err = createMgrClientForStarter()
 	require.ErrorContains(t, err, `starter additional param "enable-get-resource-group-degraded" must be a bool`)
 
 	config.UpdateGlobal(func(conf *config.Config) {
 		conf.StarterParams.ManagerAddr = ""
-		conf.StarterParams.ManagerNamespace = ""
-		conf.StarterParams.PodName = ""
-		conf.StarterParams.PodIP = ""
-		conf.StarterParams.PodNamespace = ""
 	})
 	missingManagerNamespace := "pod-name=pod-1,pod-ip=10.0.0.1,pod-namespace=ns-1"
-	require.NoError(t, applyStarterAdditionalParams(config.GetGlobalConfig(), missingManagerNamespace))
+	starterAdditionalParams = &missingManagerNamespace
 	_, err = createMgrClientForStarter()
 	require.ErrorContains(t, err, "manager notifier requires manager-addr config or manager-namespace in --starter-additional-params")
 
 	validParams := "manager-namespace=manager-ns,pod-name=pod-1,pod-ip=10.0.0.1,pod-namespace=ns-1"
-	require.NoError(t, applyStarterAdditionalParams(config.GetGlobalConfig(), validParams))
+	starterAdditionalParams = &validParams
 	cli, err := createMgrClientForStarter()
 	require.NoError(t, err)
 	require.NotNil(t, cli)
diff --git a/pkg/config/config.go b/pkg/config/config.go
index 63c3fb917c588..a979be95951f2 100644
--- a/pkg/config/config.go
+++ b/pkg/config/config.go
@@ -1094,20 +1094,8 @@ type StarterParams struct {
 	// ManagerAddr is the TiDB manager address used by the shutdown notifier.
 	// When empty and EnableManagerNotifier is true, the Starter path derives the service address from starter additional params.
 	ManagerAddr string `toml:"manager-addr" json:"manager-addr,omitempty"`
-	// ManagerNamespace captures the runtime manager namespace from --starter-additional-params.
-	// It is command-line derived runtime metadata rather than file-backed config.
-	ManagerNamespace string `toml:"-" json:"-"`
-	// PodName captures the runtime pod name from --starter-additional-params.
-	// It is command-line derived runtime metadata rather than file-backed config.
-	PodName string `toml:"-" json:"-"`
-	// PodIP captures the runtime pod IP from --starter-additional-params.
-	// It is command-line derived runtime metadata rather than file-backed config.
-	PodIP string `toml:"-" json:"-"`
-	// PodNamespace captures the runtime pod namespace from --starter-additional-params.
-	// It is command-line derived runtime metadata rather than file-backed config.
-	PodNamespace string `toml:"-" json:"-"`
 	// EnableGetResourceGroupDegraded enables degraded GetResourceGroup handling for resource control.
-	// It is command-line derived runtime metadata rather than file-backed config.
+	// It is populated from --starter-additional-params and is not file-backed config.
 	EnableGetResourceGroupDegraded bool `toml:"-" json:"-"`
 	// MaxImportDataSize is the maximum total real source data size allowed for IMPORT INTO.
 	// Zero means unlimited.
diff --git a/pkg/domain/runaway_test.go b/pkg/domain/runaway_test.go
index e0cf6861a5462..d1ae572df5b93 100644
--- a/pkg/domain/runaway_test.go
+++ b/pkg/domain/runaway_test.go
@@ -216,7 +216,6 @@ func TestResourceGroupsControllerOptions(t *testing.T) {
 		restoreResourceGroupControllerTestState(t)
 		require.NoError(t, deploymode.Set(deploymode.Starter))
 		config.UpdateGlobal(func(conf *config.Config) {
-			conf.StarterParams.PodNamespace = "starter-standard-ns"
 			conf.StarterParams.EnableGetResourceGroupDegraded = true
 		})
 
@@ -226,11 +225,10 @@ func TestResourceGroupsControllerOptions(t *testing.T) {
 		require.Equal(t, defaultDegradedModeWaitTimeout, ruConfig.DegradedModeWaitDuration)
 	})
 
-	t.Run("starter namespace alone does not enable degraded mode", func(t *testing.T) {
+	t.Run("starter without degraded flag keeps default retry settings", func(t *testing.T) {
 		restoreResourceGroupControllerTestState(t)
 		require.NoError(t, deploymode.Set(deploymode.Starter))
 		config.UpdateGlobal(func(conf *config.Config) {
-			conf.StarterParams.PodNamespace = "starter-vip-ns"
 			conf.StarterParams.EnableGetResourceGroupDegraded = false
 		})
 

From 8b9cf6d39d777d01993e762d681c48d173e7941d Mon Sep 17 00:00:00 2001
From: ystaticy <y_static_y@sina.com>
Date: Tue, 21 Jul 2026 15:50:19 +0800
Subject: [PATCH 21/21]  fix config name

Signed-off-by: ystaticy <y_static_y@sina.com>
---
 cmd/tidb-server/main.go                         | 16 ++++++++--------
 cmd/tidb-server/main_test.go                    | 10 +++++-----
 pkg/config/config.go                            |  4 ++--
 pkg/domain/resource_group_controller_options.go |  4 ++--
 pkg/domain/runaway_test.go                      | 12 ++++++------
 5 files changed, 23 insertions(+), 23 deletions(-)

diff --git a/cmd/tidb-server/main.go b/cmd/tidb-server/main.go
index b9476df7fdbf7..98891d4aec575 100644
--- a/cmd/tidb-server/main.go
+++ b/cmd/tidb-server/main.go
@@ -1351,11 +1351,11 @@ func prepareKeyspaceObservabilityForStarter(metadata map[string]string) error {
 }
 
 type starterParams struct {
-	managerNamespace               string
-	podName                        string
-	podIP                          string
-	podNamespace                   string
-	enableGetResourceGroupDegraded bool
+	managerNamespace string
+	podName          string
+	podIP            string
+	podNamespace     string
+	enableRGFallback bool
 }
 
 func parseStarterAdditionalParams(raw string) (starterParams, error) {
@@ -1398,12 +1398,12 @@ func parseStarterAdditionalParams(raw string) (starterParams, error) {
 			params.podIP = value
 		case "pod-namespace":
 			params.podNamespace = value
-		case "enable-get-resource-group-degraded":
+		case "enable-rg-fallback":
 			enable, err := strconv.ParseBool(value)
 			if err != nil {
 				return params, fmt.Errorf("starter additional param %q must be a bool: %w", key, err)
 			}
-			params.enableGetResourceGroupDegraded = enable
+			params.enableRGFallback = enable
 		default:
 			return params, fmt.Errorf("unknown starter additional param %q", key)
 		}
@@ -1416,7 +1416,7 @@ func applyStarterAdditionalParams(cfg *config.Config, raw string) error {
 	if err != nil {
 		return err
 	}
-	cfg.StarterParams.EnableGetResourceGroupDegraded = params.enableGetResourceGroupDegraded
+	cfg.StarterParams.EnableRGFallback = params.enableRGFallback
 	return nil
 }
 
diff --git a/cmd/tidb-server/main_test.go b/cmd/tidb-server/main_test.go
index 67b6ff9201039..307444e36eb9e 100644
--- a/cmd/tidb-server/main_test.go
+++ b/cmd/tidb-server/main_test.go
@@ -85,15 +85,15 @@ func TestOverrideConfigKeyspaceActivateMode(t *testing.T) {
 	fset := initFlagSet()
 	require.NoError(t, fset.Parse([]string{
 		"--keyspace-activate=true",
-		"--starter-additional-params=pod-name=pod-1,pod-ip=10.0.0.1,pod-namespace=ns-1,enable-get-resource-group-degraded=true",
+		"--starter-additional-params=pod-name=pod-1,pod-ip=10.0.0.1,pod-namespace=ns-1,enable-rg-fallback=true",
 	}))
 
 	cfg := config.NewConfig()
 	cfg.DeployMode = deploymode.Starter
 	overrideConfig(cfg, fset)
 	require.True(t, cfg.KeyspaceActivateMode)
-	require.True(t, cfg.StarterParams.EnableGetResourceGroupDegraded)
-	require.Equal(t, "pod-name=pod-1,pod-ip=10.0.0.1,pod-namespace=ns-1,enable-get-resource-group-degraded=true", *starterAdditionalParams)
+	require.True(t, cfg.StarterParams.EnableRGFallback)
+	require.Equal(t, "pod-name=pod-1,pod-ip=10.0.0.1,pod-namespace=ns-1,enable-rg-fallback=true", *starterAdditionalParams)
 }
 
 func TestSetGlobalVars(t *testing.T) {
@@ -219,10 +219,10 @@ func TestCreateMgrClientRequiresPodIdentityInStarter(t *testing.T) {
 	_, err = createMgrClientForStarter()
 	require.ErrorContains(t, err, `unknown starter additional param "unknown"`)
 
-	invalidBoolParam := "enable-get-resource-group-degraded=definitely"
+	invalidBoolParam := "enable-rg-fallback=definitely"
 	starterAdditionalParams = &invalidBoolParam
 	_, err = createMgrClientForStarter()
-	require.ErrorContains(t, err, `starter additional param "enable-get-resource-group-degraded" must be a bool`)
+	require.ErrorContains(t, err, `starter additional param "enable-rg-fallback" must be a bool`)
 
 	config.UpdateGlobal(func(conf *config.Config) {
 		conf.StarterParams.ManagerAddr = ""
diff --git a/pkg/config/config.go b/pkg/config/config.go
index a979be95951f2..07e0c58d7c460 100644
--- a/pkg/config/config.go
+++ b/pkg/config/config.go
@@ -1094,9 +1094,9 @@ type StarterParams struct {
 	// ManagerAddr is the TiDB manager address used by the shutdown notifier.
 	// When empty and EnableManagerNotifier is true, the Starter path derives the service address from starter additional params.
 	ManagerAddr string `toml:"manager-addr" json:"manager-addr,omitempty"`
-	// EnableGetResourceGroupDegraded enables degraded GetResourceGroup handling for resource control.
+	// EnableRGFallback enables resource group lookup fallback for resource control.
 	// It is populated from --starter-additional-params and is not file-backed config.
-	EnableGetResourceGroupDegraded bool `toml:"-" json:"-"`
+	EnableRGFallback bool `toml:"-" json:"-"`
 	// MaxImportDataSize is the maximum total real source data size allowed for IMPORT INTO.
 	// Zero means unlimited.
 	MaxImportDataSize configtypes.ByteSize `toml:"max-import-data-size" json:"max-import-data-size,omitempty"`
diff --git a/pkg/domain/resource_group_controller_options.go b/pkg/domain/resource_group_controller_options.go
index 8cf38c2c2644e..abb9c0f1ef749 100644
--- a/pkg/domain/resource_group_controller_options.go
+++ b/pkg/domain/resource_group_controller_options.go
@@ -47,9 +47,9 @@ func newResourceGroupsControllerOptions() []rmclient.ResourceControlCreateOption
 	opts := []rmclient.ResourceControlCreateOption{
 		rmclient.WithMaxWaitDuration(runaway.MaxWaitDuration),
 	}
-	if deploymode.IsStarter() && config.GetGlobalConfig().StarterParams.EnableGetResourceGroupDegraded {
+	if deploymode.IsStarter() && config.GetGlobalConfig().StarterParams.EnableRGFallback {
 		opts = append(opts,
-			// This Starter-only degraded path is a best-effort UX fallback for
+			// This Starter-only fallback path is a best-effort UX fallback for
 			// temporary GetResourceGroup failures. It provides a permissive
 			// group so user requests do not fail immediately; it is not intended
 			// to define a precise cross-RPC RU limit or response-side accounting
diff --git a/pkg/domain/runaway_test.go b/pkg/domain/runaway_test.go
index d1ae572df5b93..dcec631574306 100644
--- a/pkg/domain/runaway_test.go
+++ b/pkg/domain/runaway_test.go
@@ -157,7 +157,7 @@ func TestStarterDegradedResourceGroup(t *testing.T) {
 	t.Run("fallback", func(t *testing.T) {
 		restoreResourceGroupControllerTestState(t)
 		config.UpdateGlobal(func(conf *config.Config) {
-			conf.StarterParams.EnableGetResourceGroupDegraded = true
+			conf.StarterParams.EnableRGFallback = true
 		})
 
 		provider := newResourceGroupProviderStub(t, nil, newTransientGetResourceGroupErr("test-group"))
@@ -170,7 +170,7 @@ func TestStarterDegradedResourceGroup(t *testing.T) {
 	t.Run("recovery does not cache degraded group", func(t *testing.T) {
 		restoreResourceGroupControllerTestState(t)
 		config.UpdateGlobal(func(conf *config.Config) {
-			conf.StarterParams.EnableGetResourceGroupDegraded = true
+			conf.StarterParams.EnableRGFallback = true
 		})
 
 		provider := newResourceGroupProviderStub(t, nil, newTransientGetResourceGroupErr("test-group"))
@@ -216,7 +216,7 @@ func TestResourceGroupsControllerOptions(t *testing.T) {
 		restoreResourceGroupControllerTestState(t)
 		require.NoError(t, deploymode.Set(deploymode.Starter))
 		config.UpdateGlobal(func(conf *config.Config) {
-			conf.StarterParams.EnableGetResourceGroupDegraded = true
+			conf.StarterParams.EnableRGFallback = true
 		})
 
 		ruConfig := newController(t).GetConfig()
@@ -229,7 +229,7 @@ func TestResourceGroupsControllerOptions(t *testing.T) {
 		restoreResourceGroupControllerTestState(t)
 		require.NoError(t, deploymode.Set(deploymode.Starter))
 		config.UpdateGlobal(func(conf *config.Config) {
-			conf.StarterParams.EnableGetResourceGroupDegraded = false
+			conf.StarterParams.EnableRGFallback = false
 		})
 
 		ruConfig := newController(t).GetConfig()
@@ -242,7 +242,7 @@ func TestResourceGroupsControllerOptions(t *testing.T) {
 		restoreResourceGroupControllerTestState(t)
 		require.NoError(t, deploymode.Set(deploymode.Premium))
 		config.UpdateGlobal(func(conf *config.Config) {
-			conf.StarterParams.EnableGetResourceGroupDegraded = true
+			conf.StarterParams.EnableRGFallback = true
 		})
 
 		ruConfig := newController(t).GetConfig()
@@ -259,7 +259,7 @@ func TestStarterRunawaySwitchGroup(t *testing.T) {
 	restoreResourceGroupControllerTestState(t)
 
 	config.UpdateGlobal(func(conf *config.Config) {
-		conf.StarterParams.EnableGetResourceGroupDegraded = true
+		conf.StarterParams.EnableRGFallback = true
 	})
 	provider := newResourceGroupProviderStub(t, nil, newTransientGetResourceGroupErr("target-switch-group"))
 	controller := newStarterControllerForTest(t, provider)